access channel
DESCRIPTION
Access Channel. Access Channel Generation. Access Channel Modulation Parameters. Rate 1/3 Convolutional Encoder. Access Channel Block Interleaving. Access Channel Block Interleaving. Access Channel Block Interleaving (4800 X 2 bps – READ MATRIX). PCM Voice. Walsh Lookup Table. 44. 35. - PowerPoint PPT PresentationTRANSCRIPT
Access Channel
n Used by the mobile station to Initiate communication with the base station Respond to Paging Channel messages
n Has a fixed data rate of 4800 bps
n Each Access Channel is associated with only one Paging Channel
n Up to 32 access channels (0-31) are supported per Paging Channel
4800 bps
Access Channel Generation
n Message attempts are randomized to reduce probability of collision
n Two message types:A response message (in response to a base station message)A request message (sent autonomously by the mobile station)
28.8kspsConvolutional
Encoder &Repetition
R = 1/3
1.2288Mcps
Access ChannelLong Code Mask
Long PN CodeGenerator
28.8ksps Orthogonal
Modulation
307.2kcps
1.2288Mcps
Q PN (No Offset)
I PN (No Offset)
D
1/2 PNChipDelay
BlockInterleaver
Access ChannelInformation
(88 bits/Frame)
4.8 kpbs
DirectSequenceSpreading
Access Channel Modulation Parameters
Data Rate
PN Chip Rate
Code Rate
Transmit Duty Cycle
Code Symbol Rate
Modulation
Modulation Symbol Rate
Walsh Symbol Rate
Modulation Symbol Duration
PN Chips / Modulation Symbol
PN Chips / Walsh Code
4800 bits / second
1.2288
1/3
100
28800
6
4800
307.2
208.33
256
4
Megachips / second
bits / code symbol
%
code symbols / second
code symbols /modulation symbol
mod. symbols / second
Kilochips / second
microsecond
PN chips /modulation symbol
PN chips / Walsh code
Rate 1/3 Convolutional Encoder
+
+
+
g0
g1
g2
Information bits(INPUT)
Code Symbols(OUTPUT)
Code Symbols(OUTPUT)
Code Symbols(OUTPUT)
1 2 3 4 5 6 7 8
Access ChannelBlock Interleaving
n 576 modulation symbols (288 x 2) are written sequentially by columns, then read by rows in a particular order (called “bit-reverse readout of the row addresses”) every 20 ms
n Block interleaving separates repeated symbols in two identical sets: one set is transmitted during the first 10 ms and the second set, with the repetitions, is transmitted during the second 10 ms
Improves survivability of symbol information “Spreads” the effect of spurious interference and fast fading
28.8 ks ps from
C onv . Encoding& Symbol
Re petiti on (2x )
Input Array(Normal
Sequence)32 x 18
Output Array(ReorderedSequence)
32 x 18
2 8.8 ksps to
OrthogonalM odula tion
Access Channel Block Interleaving
1 17 33 49 65 81 97 113 129 145 161 177 193 209 225 241 257 273 1 17 33 49 65 81 97 113 129 145 161 177 193 209 225 241 257 273 2 18 34 50 66 82 98 114 130 146 162 178 194 210 226 242 258 274 2 18 34 50 66 82 98 114 130 146 162 178 194 210 226 242 258 274 3 19 35 51 67 83 99 115 131 147 163 179 195 211 227 243 259 275 3 19 35 51 67 83 99 115 131 147 163 179 195 211 227 243 259 275 4 20 36 52 68 84 100 116 132 148 164 180 196 212 228 244 260 276 4 20 36 52 68 84 100 116 132 148 164 180 196 212 228 244 260 276 5 21 37 53 69 85 101 117 133 149 165 181 197 213 229 245 261 277 5 21 37 53 69 85 101 117 133 149 165 181 197 213 229 245 261 277 6 22 38 54 70 86 102 118 134 150 166 182 198 214 230 246 262 278 6 22 38 54 70 86 102 118 134 150 166 182 198 214 230 246 262 278 7 23 39 55 71 87 103 119 135 151 167 183 199 215 231 247 263 279 7 23 39 55 71 87 103 119 135 151 167 183 199 215 231 247 263 279 8 24 40 56 72 88 104 120 136 152 168 184 200 216 232 248 264 280 8 24 40 56 72 88 104 120 136 152 168 184 200 216 232 248 264 280 9 25 41 57 73 89 105 121 137 153 169 185 201 217 233 249 265 281 9 25 41 57 73 89 105 121 137 153 169 185 201 217 233 249 265 28110 26 42 58 74 90 106 122 138 154 170 186 202 218 234 250 266 28210 26 42 58 74 90 106 122 138 154 170 186 202 218 234 250 266 28211 27 43 59 75 91 107 123 139 155 171 187 203 219 235 251 267 28311 27 43 59 75 91 107 123 139 155 171 187 203 219 235 251 267 28312 28 44 60 76 92 108 124 140 156 172 188 204 220 236 252 268 28412 28 44 60 76 92 108 124 140 156 172 188 204 220 236 252 268 28413 29 45 61 77 93 109 125 141 157 173 189 205 221 237 253 269 28513 29 45 61 77 93 109 125 141 157 173 189 205 221 237 253 269 28514 30 46 62 78 94 110 126 142 158 174 190 206 222 238 254 270 28614 30 46 62 78 94 110 126 142 158 174 190 206 222 238 254 270 28615 31 47 63 79 95 111 127 143 159 175 191 207 223 239 255 271 28715 31 47 63 79 95 111 127 143 159 175 191 207 223 239 255 271 28716 32 48 64 80 96 112 128 144 160 176 192 208 224 240 256 272 28816 32 48 64 80 96 112 128 144 160 176 192 208 224 240 256 272 288
Access Channel Block Interleaving(4800 X 2 bps – READ MATRIX)
1 17 33 49 65 81 97 113 129 145 161 177 193 209 225 241 257 273 9 25 41 57 73 89 105 121 137 153 169 185 201 217 233 249 265 281 5 21 37 53 69 85 101 117 133 149 165 181 197 213 229 245 261 27713 29 45 61 77 93 109 125 141 157 173 189 205 221 237 253 269 285 3 19 35 51 67 83 99 115 131 147 163 179 195 211 227 243 259 27511 27 43 59 75 91 107 123 139 155 171 187 203 219 235 251 267 283 7 23 39 55 71 87 103 119 135 151 167 183 199 215 231 247 263 27915 31 47 63 79 95 111 127 143 159 175 191 207 223 239 255 271 287 2 18 34 50 66 82 98 114 130 146 162 178 194 210 226 242 258 27410 26 42 58 74 90 106 122 138 154 170 186 202 218 234 250 266 282 6 22 38 54 70 86 102 118 134 150 166 182 198 214 230 246 262 27814 30 46 62 78 94 110 126 142 158 174 190 206 222 238 254 270 286 4 20 36 52 68 84 100 116 132 148 164 180 196 212 228 244 260 27612 28 44 60 76 92 108 124 140 156 172 188 204 220 236 252 268 284 8 24 40 56 72 88 104 120 136 152 168 184 200 216 232 248 264 28016 32 48 64 80 96 112 128 144 160 176 192 208 224 240 256 272 288
1 17 33 49 65 81 97 113 129 145 161 177 193 209 225 241 257 273 9 25 41 57 73 89 105 121 137 153 169 185 201 217 233 249 265 281 5 21 37 53 69 85 101 117 133 149 165 181 197 213 229 245 261 27713 29 45 61 77 93 109 125 141 157 173 189 205 221 237 253 269 285 3 19 35 51 67 83 99 115 131 147 163 179 195 211 227 243 259 27511 27 43 59 75 91 107 123 139 155 171 187 203 219 235 251 267 283 7 23 39 55 71 87 103 119 135 151 167 183 199 215 231 247 263 27915 31 47 63 79 95 111 127 143 159 175 191 207 223 239 255 271 287 2 18 34 50 66 82 98 114 130 146 162 178 194 210 226 242 258 27410 26 42 58 74 90 106 122 138 154 170 186 202 218 234 250 266 282 6 22 38 54 70 86 102 118 134 150 166 182 198 214 230 246 262 27814 30 46 62 78 94 110 126 142 158 174 190 206 222 238 254 270 286 4 20 36 52 68 84 100 116 132 148 164 180 196 212 228 244 260 27612 28 44 60 76 92 108 124 140 156 172 188 204 220 236 252 268 284 8 24 40 56 72 88 104 120 136 152 168 184 200 216 232 248 264 28016 32 48 64 80 96 112 128 144 160 176 192 208 224 240 256 272 288
Reverse Traffic Channel:64-ary Orthogonal Modulation
n For every six symbols in, 64 Walsh Chips are output
n Six symbols are converted to a decimal number from 0-63
n 64 Walsh Chips corresponding to that Walsh Number are output
PCM Voice
ConvolutionalEncoding
Code SymbolRepetition
BlockInterleaving
VocoderProcessing
Baseband Traffic to RF Section
OrthogonalModulationData Burst
RandomizerDirect Sequence
SpreadingQuadratureSpreadingBasebandFiltering
1 0 1 1 0 0 1 0 0 0 1 1
Symbols
3544 Walsh Lookup TableWalsh Chip within a Walsh Function
0 1 2 34 5 6 7 1 18 9 0 1
1 1 1 12 3 4 5
1 1 1 16 7 8 9
2 2 2 20 1 2 3
2 2 2 24 5 6 7
2 2 3 38 9 0 1
3 3 3 32 3 4 5
3 3 3 36 7 8 9
4 4 4 40 1 2 3
4 4 4 44 5 6 7
4 4 5 58 9 0 1
5 5 5 52 3 4 5
5 5 5 56 7 8 9
6 6 6 60 1 2 3
0123
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
4567
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
891011
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
12131415
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
Wals
16171819
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
hFu
20212223
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0n
cti
24252627
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
on I
28293031
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 0 1 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 0 1 0 0 1
ndex
32333435
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
36373839
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 040
414243
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
44454647
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
48495051
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
52535455
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
56575859
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
60616263
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 0 1 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
1 1 1 11 0 1 01 1 0 01 0 0 1
1 1 1 11 0 1 01 1 0 01 0 0 1
0 0 0 00 1 0 10 0 1 10 1 1 0
64 chip patterns of WC #35
10001…11010
Access Channel Long Code Mask
An Access Channel is scrambled by the long code, offset by a mask constructed as follows:
Where:
ACN is the Access Channel Number,
PCN is the Number of the associated Paging Channel
BASE_ID is the base station identification number, and
PILOT_PN is the Pilot short PN code offset index
11 000 111 1 PCNACN BASE_ID PILOT_PN
41 33 32 028 27 25 24 9 8
Access Channel Slot Structure
Access transmission max length:
20 x (4 + PAM_SZ + MAX_CAP_SZ) ms 96 x (4 + PAM_SZ + MAX_CAP_SZ) bits
Preamble Message Capsule
Frame Frame Frame Frame
20 ms96 bits
AccessSlot
Boundary
Access Slot n Access Slot n+1
PAM_SZ MAX_CAP_SZ
4800 bps
• The PAM_SZ parameter determines the size of the Access Channel Preamble.
• The MAX_CAP_SIZE determines the size of the Access Channel Message Capsule.
• Actual transmission starts with the preamble at the beginning of the slot plus a random amount of time RN, measured in chips, calculated with a hashing algorithm that uses the mobile’s ESN and a parameter sent by the base station (discussed later).
Access Channel Slot Structure
Access Channel Structure
Access Channel Message Padding
CRC
20 ms
96 bits
8 x MSG_LENGTH
8 bits 30 bits
MSG_LENGTH
2-842 bits
as
required
Access Channel Frame
Message Body
20 x (4 + PAM_SZ + MAX_CAP_SZ) ms96 x (4 + PAM_SZ + MAX_CAP_SZ) bits
4800 bps
Nf =Number of AccessChannel Frames
needed for message transmissionT = Encoder Tail Bits
(eight zeroes)
Access Channel Frame Body
1 + PAM_SZ frames96 x (1 + PAM_SZ) bits
96 x Nf bits (not exceeding 3 + MAX_CAP_SZ frames)
Access Channel Slot
TAccess Channel Preamble
Access Channel Message Capsule
T TT
88 x Nf bits
• ACCESS CHANNEL SLOT – Group of contiguous Access Channel frames where an Access Channel Message can be contained. As the Access Slot length may differ from base station to base station, a mobile station must determine the beginning and length of the Access Channel slot prior to transmission.
• All access channels associated with a particular Paging Channel have the same slot size, and all the slots begin at the same time.
• Each Access Channel Frame contains 96 bits (20 ms frame at 4800 bps). Each Access Channel frame consists of 88 information bits and eight Encoder Tail Bits.
• The Encoder Tail Bits are a fixed sequence of bits (eight zeroes) added to the end of a block of data (88 bits) to reset (flush) the convolutional encoder to a known state (all zeroes).
• The Access Channel Preamble consists of frames of 96 zeroes that are transmitted at the 4800 bps rate. The access Channel Preamble is transmitted to aid the base station in acquiring an Access Channel transmission.
Access Channel Structure
Access Channel Probing
SystemTime
See nextfigure
ONE ACCESS CHANNEL SLOT
Access Channel Frame (20 ms)
ACCESS CHANNELPREAMBLE
(Modulation Symbol 0)
ACCESS CHANNELMESSAGE CAPSULE
ACTUAL ACCESS PROBE TRANSMISSION
PN Randomization Delay = RN chips = RN x 0.8138 µs
ACCESSPROBE
1 + PAM_SZ(1 - 16 frames)
3 + MAX_CAP_SZ(3 - 10 frames)
4 + PAM_SZ + MAX_CAP_SZ(4 - 26 frames)
Access ChannelSlot and Frame
Boundary
• Each access probe consists of an Access Channel Preamble and an Access Channel Message Capsule.
• The timing of access probes and access probe sequences is expressed in term of Access Channel slots. The transmission of an access probe begins shortly after the start of an Access Channel Slot. The precise timing of the Access Channel transmissions in an access attempt is determined by a procedure called PN randomization. For each access attempt, the mobile station computes a delay, RN from 0 to 2 PROBE_PN_RAN - 1 PN chips using a non-random hash function that depends on its ESN. The mobile station delays its transmit time by RN PN chips.
• The RN parameter, which appears on the illustration, is calculated as follows:• RN – PN Randomization Delay (0 to 511 chips). Generated before every
sequence, between 0 and 2 PROBE_PN_RAN - 1, by hash, using ESN_S.
Access Channel Probing
Access Channel Probing
AccessProbe 1
AccessProbe 1
AccessProbe 1
AccessProbe 1
Access Probe1 + NUM_STEP
(16 max)
SystemTime
TA RT TA RT TA RT TA
PI
PI
PI
IP(InitialPower)
See previousfigure
ACCESSPROBE
SEQUENCE
Select Access Channel (RA)
initialize transmit power
• Within an access attempt, probes are grouped into access probe sequences. Each access probe sequence consists of up to 1 + NUM_STEP access probes, all transmitted on the same Access Channel. The Access Channel used for each access probe sequence is chosen pseudorandomly from among the Access Channels associated with the current Paging Channel.
– The first access probe in an access probe sequence is transmitted at a specified power level relative to the nominal open-loop power level (see Lesson 7). Each subsequent access probe is transmitted at a power level that is a specified amount higher than the previous access probe. Between access probes, the mobile station “gates off” the transmitter.
• IP – Initial Open-Loop Power.• PI – Power Increment.• RA - Access Channel Number.• TA – Acknowledgment Response Timeout.• RT – Probe Backoff.
Access Channel Probing
Access Channel Probing
Seq 2 Seq 3
Seq MAX_REQ_SEQ
(15 max)
RSRS
Access Attempt
PD
System
Time
Access Probe Sequence 1
REQUESTATTEMPT
Request message ready for transmission
PD PD
Seq 2 Seq 4Seq 3
Seq MAX_RSP_SEQ(15 max)
RSRS
Access Attempt
RS
System
Time
Access Probe Sequence 1
RESPONSEATTEMPT
Response message ready for transmission
Access Channel Probing• The mobile station transmits on the Access Channel using a random access procedure. Many
parameters of the random access procedure are supplied by the base station in the Access Parameters Message.
• The entire process of sending one message and receiving (or failing to receive) an acknowledgment for that message is called an access attempt. Each transmission on the access attempt is called an access probe. The mobile station transmits the same message in each access probe in an access attempt. Within an access attempt, access probes are grouped into access probe sequences.
– The pseudorandom nature of this process reduces the probability that the access attempts of this mobile station will experience contention with the access attempts of another mobile station.
• MAX_REQ_SEQ – Maximum number of access probe sequences for an Access Channel request (value must be greater than 0).
• MAX_RSP_SEQ – Maximum number of access probe sequences for an Access Channel response (value must be greater than 0).
• BKOFF – Access Channel probe sequence backoff range. This parameter is set by the base station to one less than the maximum number of slots a mobile station is to delay due to random backoff between successive access probe sequences and before the first access probe sequence of a response access.
• RS – Sequence backoff. Random value between 0 and 1 + BKOFF; generated before every sequence (except the first sequence). Maximum range of values is 0 to 16 slots
• PD – Persistence delay. Delay continues slot-by-slot until persistence test (run every slot) passes
Access Parameters Message(Paging Channels)
M SG_TYP E (‘0 00 000 10’)
PIL OT_ PN
ACC_ MSG _SEQ
ACC_CHAN
NOM _PW R
IN IT_PW R
PW R_ STEP
P SIST(14)
8
9
6
5
4
5
3
3
P SIST(15)
M SG_P SIST
RE G_PSI ST
P ROBE_ PN_ RAN
ACC_ TM O
PROBE_BKO FF
BKOFF
MAX_REQ_ SEQ
M AX _RSP_S EQ
AUTH
RA ND
NOM _PW R_ EXT
RES ERV ED (‘00 000 0’)
NUM_ STEP
3
3
3
4
4
4
4
4
4
2
0 o r 32
1
6
4
M AX_CAP _SZ
PAM_ SZ
PS IST(0 -9 )
PSIST(10)
PSIST(11)
PSIST(12)
PSIST(13)
3
4
6
3
3
3
3
Fiel dLength(bits)
ACCESS PROBING
RN
TA
RT
RS
IP
RA
IP
PI
PD
PD
Access Parameters Message(Paging Channels)
• PILOT_PN – Pilot PN sequence offset for this base station, in units of 64 PN chips.• ACC_MSG_SEQ – Access parameters message sequence number.• ACC_CHAN – One less than the number of access channels associated with the paging
channel on which this message was received.• NOM_PWR – Nominal Transmit Power Offset. If the correction factor to be used by the
mobile stations in the open-loop power estimation is between -24 dB and -9 dB, the NOM_PWR parameter must be set to 16 dB plus the correction factor, and NOM_PWR_EXT must be set to ‘1’. Otherwise (the correction factor is in the range -8 dB to 7 dB inclusive), the NOM_PWR parameter must be set to the correction factor, and NOM_PWR_EXT must be set to ‘0’. The NOM_PWR is expressed as a two’s complement value in units of 1 dB.
• INIT_PWR – InitiaL Power. This is the correction factor to be used by the mobile stations in the open-loop power estimation for initial transmission on an Access Channel, expressed as a two’s complement value in units of 1 dB.
• PWR_STEP - Power Increment. This is the value by which mobile stations are to increase their transmit power between successive probes in an access probe sequence, in units of 1 dB.
Access Parameters Message(Paging Channels)
• NUM_STEP – Number of Access Probes. This parameter is one less than the maximum number of access probes mobile stations are to transmit in a single access probe sequence.
• MAX_CAP_SZ – Maximum Access Channel capsule size. The actual max size (in bytes) is the value in this field (0-7) plus three.– PAM_SZ – Access Channel preamble length. The actual max size (in bytes) is the value in this field (0-15) plus one.
• PSIST(0-9) – Persistence value for mobile stations in access overload classes 0 through 9. If set to ‘111111’, a mobile station in overload classes 0 though 9 is not allowed to access the CDMA system. Anything else is the persistence value to be used by the mobile station when attempting to access the system.
– PSIST(10) through PSIST(15) – Persistence value for mobile stations in the corresponding access overload class. If set to ‘111’, a mobile station in this overload class is not allowed to access the CDMA system. Anything else is the persistence value to be used by the mobile station when attempting to access the system.
• MSG_PSIST – Persistence modifier for Access Channel attempts for data burst message transmissions. The mobile station multiplies its transmission probability by 2 –MSG_PSIST for such attempts.
• REG_PSIST – Persistence modifier for Access Channel attempts for registrations that are not responses to a “Registration Request Order”. The mobile station multiplies its transmission probability by 2 –REG_PSIST for such attempts.
• PROBE_PN_RAN – Time Randomization for Access Channel Probes. This parameter is used to calculate the number RN of PN chips a mobile station delays its transmission from System Time.
• ACC_TMO – Acknowledgment Timeout. This parameter is set to two less than the length of time mobile stations are to wait after the end of an Access Channel transmission before determining that the base station did not receive the transmission (in 80 ms units).
• PROBE_BKOFF – Access Channel Probe Backoff Range. This parameter is set to one less than the maximum number of slots mobile stations are to delay due to random backoff between consecutive access probes.
• MAX_REQ_SEQ – Maximum number of access probe sequences for an Access Channel request (value must be greater than 0).• MAX_RSP_SEQ – Maximum number of access probe sequences for an Access Channel response (value must be greater than 0).• AUTH – Authentication mode. ‘01’ if mobile stations are to include authentication data in their Access Channel messages; ‘00’ if not.• RAND – If AUTH is set to ‘01’, this field is set to the random challenge value to be used by the mobile station for authentication. Only in this
case shall this field be included.• NOM_PWR_EXT – Extended Nominal Transmit Power. If the correction factor to be used by the mobile stations in the open-loop power
estimation is between -24 dB and -9 dB, this parameter must be set to ‘1’. Otherwise (the correction factor is in the range -8 dB to 7 dB inclusive), this parameter must be set to ‘0’.
Access Channel Probing Parameters
n RA - Access Channel Number. Random value between 0 and ACC_CHAN; generated before every sequence (maximum range is 0 - 31).
n IP – Initial Open-Loop Power. Calculated in dBm as follows:
IP = k - Mean Input Power (dBm) + NOM_PWR (dB)
- NOM_PWR_EXT x 16 (dB) + INIT_PWR (dB)
where k = -73 for 800 MHz Cellular and -76 for 1900 PCS.
n PI – Power Increment. Equal to PWR_STEP in dB (range is 0 to 7 dB).
n TA – Acknowledgment Response Timeout (timeout from the end of the slot). Calculated in ms as follows (range is 160 to 1360 ms):
TA = 80 x (2 + ACC_TMO)
n RT – Probe Backoff. Random value between 0 and 1 + PROBE_BKOFF; generated before every sequence (maximum range is 0 - 16 slots).
n RS – Sequence backoff . Random value between 0 and 1 + BKOFF; generated before every sequence (except the first sequence). Maximum range of values is 0 to 16 slots
n PD – Persistence delay. (Value used to implement the “persistence test”).
n RN – PN Randomization Delay. (0 to 511 chips) . Generated before every sequence, between 0 and 2 PROBE_PN_RAN - 1, by hash, using ESN_S.
Access Procedure Example
ACCES SS UCCESSFUL
B egin
AccessChannelResponse
If beginning of slotgenerate RP
RP < P
Generate Randomnumber RA between 0
and ACC_CHAN
Initializetransmit power
Transmit probe on AccessChannel RA at system timing
plus RN chips. Set TA
Ackreceived
Tim er TAe xp ire d
PROBE •NUM_STEP
PROBE = PROBE + 1
SEQ = SEQ + 1
SEQ •MAX_REQ_SEQ(MAX_RSP_SEQ)
Generate randomnumber RT between
0 and(PROBE_BKOFF + 1)
Wait RT slots
Increment transmitpower by
PWR_STEP dB
Access failure; enterSystem Determination Substate
or theMobile Station Initialization State
Generate randomnumber RS between0 and (BKOFF + 1)
W ait RS slots
PROBE = 0SEQ = 0
Hash using ESN_Sand PROBE_PN_RAN
to obtain RN
Yes
NoYe s
Y es
Yes
YesNo
No
No
No
Cont.• The section of this diagram, where a value is generated for “RP” and then compared to
the probability “P”, describes the implementation of the “persistence test”. • “P” is calculated by a formula that varies, according to the type of message being sent in
the access probe. This calculation always involve the persistence parameter PSIST(n); where “n” is the overload class assigned to the mobile station. If the Access Channel request is a registration, the REG_PSIST parameter is also involved in the calculation. If the Access Channel request is a message transmission, the MSG_PSIST parameter is also involved in the calculation.
• All these parameters are contained in the “System Parameters Message”.• For a certain value of the PSIST (refer to J-STD 008 for details) parameter, the value of
“P” is defined to be ‘0’; and when P is ‘0’, the access attempt always fails (by definition), the mobile station stops the access attempt, and enters the System Determination Substate of the Mobile Station Initialization State with an access denied indication.
• If P is not ‘0’, a value “RP” is randomly generated in the 0-1 interval, and compared with the “P”, which is also in the 0-1 interval.
• If RP is less than the current value of P for the type of this access attempt, the test succeeds and the first access probe of the probe sequence is sent; otherwise a new value for RP is calculated and the comparison repeated until it is successful.
Access Channel Messages
The following messages are sent on the Access Channel:
n Registration Message
n Order Message
n Data Burst Message
n Origination Message
n Page Response Message
n Authentication Challenge Response Message
n Status Response Message
n TMSI Assignment Completion Message
Access Channel Messages
• Registration Message - Sent by the mobile station on the Access Channel to register with the system. (Discussed later in the Registration lesson).
• Order Message - Sent by the mobile station to the base station on the Access Channel or on the Reverse Traffic Channel, with a request consisting of a 6-bit order code and zero or more order-specific fields.
• Data Burst Message - Sent by the mobile station to the base station on the Access Channel or on the Reverse Traffic Channel, containing a “data burst” (as defined by TIA/EIA document TBS-58)
• Origination Message - Sent by the mobile station to the base station on the Access Channel with the dialed number and other information like Slotted Mode & Slot Cycle Index, whether the mobile station is willing to accept calls, requested mode of operation (CDMA only, Wide Analog only, etc.).
• Page Response Message - Sent by the mobile station to the base station on the Access Channel in response to a Paging Message. Some of the information fields contained in this message are the same as fields contained in the Origination Message.
• Authentication Challenge Response Message - This message, sent by the mobile station to the base station on the Access Channel or on the Reverse Traffic Channel, contains the18-bit value AUTH_SIGNATURE calculated at the mobile station by executing the Auth-Signature procedure following reception of an Authentication Challenge Message on the Paging Channel or on the Forward Traffic Channel.
– Status Response Message - Sent by the mobile station to the base station on the Access Channel or on the Reverse Traffic Channel in response to a Status Request Message. It includes all the Information Records requested in a Status Request Message received on the Paging Channel or on the Forward Traffic Channel. (Example of Information Record types are Terminal Information, Roaming Information, IMSI, ESN, etc.)
• TMSI Assignment Completion Message - Sent by the mobile station to the base station on the Access Channel or on the Reverse Traffic Channel after completing the process initiated by the reception of a TMSI Assignment Message on the Paging Channel or on the Forward Traffic Channel,
Order Message(Access Channels)
Field Length (bits)
MSG_TYPE (‘00000010’) 8
ACK_SEQ 3
MSG_SEQ 3
ACK_REQ 1
VALID_ACK 1
ACK_TYPE 3
MSID_TYPE 3
MSID_LEN 4
MSID 8 x MSID_LEN
RESERVED (‘00’) 2
ORDER 6
ADD_RECORD_LEN 3
Order-specific fields (if used) 8 x ADD_RECORD_LEN
RESERVED (‘00000’) 5
Used by the Acknowledgment
Procedures(Reverse Direction)
Mobile StationIdentification
Order Message – Access Channel
• ORDER – The mobile station sets this field to the Order Code for this type of Order Message.
• ADD_RECORD_LEN – This field is set by the mobile station to the number of octets in the order-specific fields contained in this message
• Order-specific-fields – Any fields added here by the mobile station (including the Order Qualification ORDQ) depend on the specific Order Code present in this message.
Selected Order Codes(Access and Reverse Traffic
Channels)
Base Station Challenge Order
SSD UpdateConfirmation Order
SSD UpdateReject Order
Request Wide AnalogService Order
Request Narrow AnalogService Order
Mobile StationAcknowledgment Order
Release Order(w/wo power down indicator)
Long Code Transition Request(request public/private)
Long Code Transition Response(use public/private)
Connect Order
Continuous DTMF Tone Order(code indicates tone to play)
Continuous DTMF Tone Order(stop playing tone)
A RT A RT
Data Burst Message(Access Channels)
M SG_ TY PE (‘00 00 001 1’) 8
Fie ld Le ngth (bits)
A CK _SE Q 3
M SG _SE Q 3
ACK_ REQ 1
V ALID_ ACK 1
A CK _TYP E 3
MS ID_ TYPE 3
M SID_ LEN 4
M SID 8 x M SID_L EN
AUTH_M ODE 2
AUTHR 0 or 1 8
RANDC 0 o r 8
COUNT 0 o r 6
M SG _NUM BER 8
BURST_ TYPE 6
NUM_ MS GS 8
NUM _FIE LDS 8
CHARi 8
NUM_ FIELD occ ur rence s of the following fiel d:
Ack.
Addr.
Auth.
Data Burst Message (Access Channel)
• MSG_NUMBER – The base station sets this field to the number of this message within the data burst stream.
• BURST_TYPE – This field contains the value defined in document TSB-58 for this type of data burst.
– NUM_MSGS – Number of messages in this data burst stream.
• CHARi – The message contains NUM_FIELD occurrences of this field, each containing a corresponding octet of the data burst stream.
Origination Message(Access Channels)
Auth ent ica tion
MS G_TYP E (‘0 00 00 100 ’) 8
Fie ld Le ngth (bits )
ACK_ SEQ 3
M SG_ SEQ 3
ACK_ RE Q 1
VA LID_A CK 1
ACK_ TYPE 3
M SID_ TY PE 3
M SID_L EN 4
M SID 8 x MS ID_LE N
AUTH_ MO DE 2
AUTHR 0 or 18
RA NDC 0 or 8
CO UNT 0 or 6
M OB_ TERM 1
S LOT_CY CL E_I NDEX 3
M OB _P_ RE V 8
EX T_ SCM 1
RES ERVED (‘0 ’) 1
S LOTTED_M ODE 1
RES ERVED (‘000 00 ’) 5
REQ UE ST_M ODE 3
S PECIAL _S ERVICE 1
Ackn ow led gm ent
M ob ileSta tion ID
SERVI CE _OP TI ON 0 or 16
PM 1
NAR_ AN_CAP 1
RES ERVED (‘0 ’s) 0 -7 (as n eed ed )
DIGIT_ MO DE 1
NUM BER_TYPE 0 or 3
NUMBER_ PLAN 0 or 4
MORE_ FIELDS 1
NUM _FIELDS 8
CHARi 4 or 8
NUM _FIE LD oc curre nc es of the foll ow ing fi eld:
Origination Continuation
• DIGIT_MODE – Digit mode indicator. The mobile station sets this field to the DIGIT_MODE value from the Access Channel Origination Message for which this message is a continuation.
• NUM_FIELDS – Number of dialed digits in this message. The mobile station sets this field to the number of dialed digits included in this message.
• CHARi – A dialed digit or character. The mobile station includes NUM_FIELDS occurrences of this field, one for each dialed digit after those sent in the Access Channel Origination Message of which this message is a continuation. If the DIGIT_MODE field is set to ‘0’, the mobile station sets each occurrence of this field to the DTMF code value corresponding to the dialed digit (see previous slide). If the DIGIT_MODE field is set to ‘1’, the personal station sets each occurrence of this field to the ASCII representation corresponding to the dialed digit, with the most significant bit set to ‘0’.
Origination Continuation Message(Reverse Traffic Channels)
MSG_TYPE (‘00001001’) 8
Field Length (bits)
ACK_SEQ 3
MSG_SEQ 3
ACK_REQ 1
ENCRYPTION 2
DIGIT_MODE 1
NUM_FIELDS 8
CHARi 4 or 8
RESERVED (‘0’s) 0 - 7 (as needed)
NUM_FIELDS occurrences of the following field:
Ack.
Reverse Traffic Channel
n Used when a call is in progress to send Voice traffic from the subscriber Response to commands/queries from the base station Requests to the base station
n Supports variable data rate operation for 8 Kbps vocoder
Rate Set 1 - 9600, 4800, 2400 and 1200 bps Multiplex Option 1
13 Kbps vocoder Rate Set 2 - 14400, 7200, 3600, 1800 bps Multiplex Option 2
R everse Traff ic Channel
Reverse Traffic Channel Generation
960 0 bps480 0 bps240 0 bps120 0 bps
or
144 00 bps720 0 bps360 0 bps180 0 bps
28.8ks ps
R = 1/3
1.2288Mcps
User Addres sMas k
LongPN Code
Ge nera tor
28.8k sps Orthogona l
Modulation
Data Burs tRandomize r
307. 2kcps
1.2288M cps
Q PN(no offset)
I P N(no offs et)
D
1/2 PNChip
Delay
D irectSeque nceSpreading
R = 1/2
ConvolutionalEncoder &Repetiti on
B loc k
Interleave r
Reverse Traffic ChannelModulation Parameters
Data Rate (8 Kb vocoder) (13 Kb vocoder)
Bits / Second 960014400
48007200
24003600
12001800
PN Chip Rate Mega Chips / Second1.2288 1.2288 1.2288 1.2288
Code Rate (8 Kb) (13 Kb)
Bits Per Code Symbol1 / 31 / 2
1 / 31 / 2
1 / 31 / 2
1 / 31 / 2
PN Chips / Mod. Symbol PN Chips / Mod. Symbol256 256 256 256
PN Chips / Walsh Chip PN Chips / Walsh Chip4 4 4 4
Code Symbol Rate Code Symbols / Second28800 14400 7200 3600
Mod. Symbol Rate Mod. Symbols / Second4800 4800 4800 4800
Transmit Duty Cycle %100 50 25 12.5
Mod. Symbol Duration Microseconds208.33 208.33 208.33 208.33
Modulation Code Symbols / Mod. Symbols6 6 6 6
Walsh Chip Rate Kilo chips / Second307.2 307.2 307.2 307.2
Reverse Traffic Channel Frame Structure
TransmissionRate Total Erasure Information CRC Tail Bits
9600 192 — 172 12 8
4800 96 — 80 8 8
2400 48 — 40 — 8
1200 24 — 16 — 8
14400 288 1 267 12 8
7200 144 1 125 10 8
3600 72 1 55 8 8
1800 36 1 21 6 8
1
2
Number of Bits per FrameRateSet
Reverse Traffic Channel Convolutional Encoder
n Convolutional encoding: Results in 3 code symbols out for each bit in, at Rate Set
1, and in 2 code symbols out for each bit in, at Rate Set 2 Also allows for reduction in transmit power Reduces overall noise & increases capacity
n Symbol repetit ion maintains a constant 28.8 ksps output to block interleaver
PCM Voice
Convoluti ona l
Encoding
Code S ymbol
Re pe tition
BlockInte rleav ing
Orthogona lModulation
Data Burs t
Randomizer
D irect Se que nce
Spreading
Qua drature
Spreading
Base ba ndFilteri ng
Vocoder
Proces sing
Baseband Traffic to RF Section
VariableRate
Outputfrom
Vocoder
R=1/3 K=9 Convolutional
EncoderR=1/2 K=9
28 .8 k spsto Bl oc k
Inte rlea ver
28 .8 k sps (No repetiti on)
14.4 ks ps (2 X repetiti on)7. 2 ks ps (4 X repetition)
3. 6 ks ps (8 X repetition)
28 .8 k sps (No repetiti on)
14.4 ks ps (2 X repetiti on)7. 2 ks ps (4 X repetition)
3. 6 ks ps (8 X repetition)
SymbolRepetition
9.6 kbps
4.8 kbps2.4 kbps
1.2 kbps
14. 4 k bps
7. 2 k bps 3. 6 k bps
1. 8 k bps
Reverse Traffic Channel:Block Interleaving
PCM Voice
C onvolutionalEnc oding
C ode SymbolR epetiti on
B lockInterlea ving
V oc ode r
Proce ssi ng
Baseband Traffic to RF Section
2 8.8 ksps
From C oding& Sy mbol
R epetit ion
n 20 ms symbol blocks are sequentially reordered
n Combats the effects of fast fading
n Separates repeated symbols at 4800 bps and below
Improves survivability of symbol data “Spreads” the effect of spurious interference
Output Array(ReorderedSequence)
32 x 18
28.8 ks ps to
Orthogona lModul ation
Orthogonal
M odula tion
D ata Burst
Ra ndomizer
D irec t SequenceSprea di ng
QuadratureSprea di ng
B as ebandFi lte ring
Input Array(Normal
Sequence)32 x 18
Reverse Traffic Channel Block Interleaving(9600 and 14400 bps)
WRITE
R E A D
1 33 65 97 129 161 193 225 257 289 321 353 385 417 449 471 503 535 2 34 66 98 130 162 194 226 258 290 322 354 386 418 450 472 504 536
3 35 67 99 131 163 195 227 259 291 323 355 387 419 451 473 505 537 4 36 68 100 132 164 196 228 260 292 324 356 388 420 452 474 506 538 5 37 69 101 133 165 197 229 261 293 325 357 389 421 453 475 507 549
6 38 70 102 134 166 198 230 262 294 326 358 390 422 454 476 508 540 7 39 71 103 135 167 199 231 263 295 327 359 391 423 455 477 509 541
8 40 72 104 136 168 200 232 264 296 328 360 392 424 456 478 510 542 9 41 73 105 137 169 201 233 265 297 329 361 393 425 457 479 511 54310 42 74 106 138 170 202 234 266 298 330 362 394 426 458 470 512 544
11 43 75 107 139 171 203 235 267 299 331 363 395 427 459 481 513 54512 44 76 108 140 172 204 236 268 300 332 364 396 428 460 482 514 546
13 45 77 109 141 173 205 237 269 301 333 365 397 429 461 483 515 54714 46 78 110 142 174 206 238 270 302 334 366 398 430 462 484 516 54815 47 79 111 143 175 207 239 271 303 335 367 399 431 463 485 517 559
16 48 80 112 144 176 208 240 272 304 336 368 400 432 464 486 518 55017 49 81 113 145 177 209 241 273 305 337 369 401 433 465 487 519 551
18 50 82 114 146 178 210 242 274 306 338 370 402 434 466 488 520 55219 51 83 115 147 179 211 243 275 307 339 371 403 435 467 489 521 55320 52 84 116 148 180 212 244 276 308 340 372 404 436 468 480 522 554
21 53 85 117 149 181 213 245 277 309 341 373 405 437 469 491 523 55522 54 86 118 150 182 214 246 278 310 342 374 406 438 470 492 524 556
23 55 87 119 151 183 215 247 279 311 343 375 407 439 471 493 525 55724 56 88 120 152 184 216 248 280 312 344 376 408 440 472 494 526 55825 57 89 121 153 185 217 249 281 313 345 377 409 441 473 495 527 569
26 58 90 122 154 186 218 250 282 314 346 378 410 442 474 496 528 57027 59 91 123 155 187 219 251 283 315 347 379 411 443 475 497 529 571
28 60 92 124 156 188 220 252 284 316 348 380 412 444 476 498 530 57229 61 93 125 157 189 221 253 285 317 349 381 413 445 477 499 531 57330 62 94 126 158 190 222 254 286 318 350 382 414 446 478 500 532 574
31 63 95 127 159 191 223 255 287 319 351 383 415 447 479 501 533 57532 64 96 128 160 192 224 256 288 320 352 384 416 448 470 502 534 576
WRITE
R E A D
1 17 33 49 65 81 97 113 129 145 161 177 193 209 225 241 257 273
1 17 33 49 65 81 97 113 129 145 161 177 193 209 225 241 257 273 2 18 34 50 66 82 98 114 130 146 162 178 194 210 226 242 258 274
2 18 34 50 66 82 98 114 130 146 162 178 194 210 226 242 258 274 3 19 35 51 67 83 99 115 131 147 163 179 195 211 227 243 259 275 3 19 35 51 67 83 99 115 131 147 163 179 195 211 227 243 259 275
4 20 36 52 68 84 100 116 132 148 164 180 196 212 228 244 260 276 4 20 36 52 68 84 100 116 132 148 164 180 196 212 228 244 260 276
5 21 37 53 69 85 101 117 133 149 165 181 197 213 229 245 261 277 5 21 37 53 69 85 101 117 133 149 165 181 197 213 229 245 261 277 6 22 38 54 70 86 102 118 134 150 166 182 198 214 230 246 262 278
6 22 38 54 70 86 102 118 134 150 166 182 198 214 230 246 262 278 7 23 39 55 71 87 103 119 135 151 167 183 199 215 231 247 263 279
7 23 39 55 71 87 103 119 135 151 167 183 199 215 231 247 263 279 8 24 40 56 72 88 104 120 136 152 168 184 200 216 232 248 264 280 8 24 40 56 72 88 104 120 136 152 168 184 200 216 232 248 264 280
9 25 41 57 73 89 105 121 137 153 169 185 201 217 233 249 265 281 9 25 41 57 73 89 105 121 137 153 169 185 201 217 233 249 265 281
10 26 42 58 74 90 106 122 138 154 170 186 202 218 234 250 266 28210 26 42 58 74 90 106 122 138 154 170 186 202 218 234 250 266 28211 27 43 59 75 91 107 123 139 155 171 187 203 219 235 251 267 283
11 27 43 59 75 91 107 123 139 155 171 187 203 219 235 251 267 28312 28 44 60 76 92 108 124 140 156 172 188 204 220 236 252 268 284
12 28 44 60 76 92 108 124 140 156 172 188 204 220 236 252 268 28413 29 45 61 77 93 109 125 141 157 173 189 205 221 237 253 269 28513 29 45 61 77 93 109 125 141 157 173 189 205 221 237 253 269 285
14 30 46 62 78 94 110 126 142 158 174 190 206 222 238 254 270 28614 30 46 62 78 94 110 126 142 158 174 190 206 222 238 254 270 286
15 31 47 63 79 95 111 127 143 159 175 191 207 223 239 255 271 28715 31 47 63 79 95 111 127 143 159 175 191 207 223 239 255 271 28716 32 48 64 80 96 112 128 144 160 176 192 208 224 240 256 272 288
16 32 48 64 80 96 112 128 144 160 176 192 208 224 240 256 272 288
Reverse Traffic Channel Block Interleaving(4800 and 7200 bps)
Power Control Groups 1 17 33 49 65 81 97 113 129 145 161 177 193 209 225 241 257 273 2 18 34 50 66 82 98 114 130 146 162 178 194 210 226 242 258 274 1 17 33 49 65 81 97 113 129 145 161 177 193 209 225 241 257 273 2 18 34 50 66 82 98 114 130 146 162 178 194 210 226 242 258 274 3 19 35 51 67 83 99 115 131 147 163 179 195 211 227 243 259 275 4 20 36 52 68 84 100 116 132 148 164 180 196 212 228 244 260 276 3 19 35 51 67 83 99 115 131 147 163 179 195 211 227 243 259 275 4 20 36 52 68 84 100 116 132 148 164 180 196 212 228 244 260 276 5 21 37 53 69 85 101 117 133 149 165 181 197 213 229 245 261 277 6 22 38 54 70 86 102 118 134 150 166 182 198 214 230 246 262 278 5 21 37 53 69 85 101 117 133 149 165 181 197 213 229 245 261 277 6 22 38 54 70 86 102 118 134 150 166 182 198 214 230 246 262 278 7 23 39 55 71 87 103 119 135 151 167 183 199 215 231 247 263 279 8 24 40 56 72 88 104 120 136 152 168 184 200 216 232 248 264 280 7 23 39 55 71 87 103 119 135 151 167 183 199 215 231 247 263 279 8 24 40 56 72 88 104 120 136 152 168 184 200 216 232 248 264 280 9 25 41 57 73 89 105 121 137 153 169 185 201 217 233 249 265 28110 26 42 58 74 90 106 122 138 154 170 186 202 218 234 250 266 282 9 25 41 57 73 89 105 121 137 153 169 185 201 217 233 249 265 28110 26 42 58 74 90 106 122 138 154 170 186 202 218 234 250 266 28211 27 43 59 75 91 107 123 139 155 171 187 203 219 235 251 267 28312 28 44 60 76 92 108 124 140 156 172 188 204 220 236 252 268 28411 27 43 59 75 91 107 123 139 155 171 187 203 219 235 251 267 28312 28 44 60 76 92 108 124 140 156 172 188 204 220 236 252 268 28413 29 45 61 77 93 109 125 141 157 173 189 205 221 237 253 269 28514 30 46 62 78 94 110 126 142 158 174 190 206 222 238 254 270 28613 29 45 61 77 93 109 125 141 157 173 189 205 221 237 253 269 28514 30 46 62 78 94 110 126 142 158 174 190 206 222 238 254 270 28615 31 47 63 79 95 111 127 143 159 175 191 207 223 239 255 271 28716 32 48 64 80 96 112 128 144 160 176 192 208 224 240 256 272 28815 31 47 63 79 95 111 127 143 159 175 191 207 223 239 255 271 28716 32 48 64 80 96 112 128 144 160 176 192 208 224 240 256 272 288
Notice that, with this scheme, every FOUR rows produce TWO identical sequences of 36 modulation symbols:
(1-2), (1-2), (3-4), (3-4), (5-6), (5-6), (7-8), (7-8), (9-10, (9-10), (11-12), (11-12), (13-14), (13-14), (15-16), (15-16)
Reverse Traffic Channel Block Interleaving(2400 and 3600 bps)
WRITE
R E A D
1 9 17 25 33 4 1 49 57 65 7 3 81 89 97 1 05 1 13 1 21 12 9 13 7
1 9 17 25 33 4 1 49 57 65 7 3 81 89 97 1 05 1 13 1 21 12 9 13 71 9 17 25 33 4 1 49 57 65 7 3 81 89 97 1 05 1 13 1 21 12 9 13 7
1 9 17 25 33 4 1 49 57 65 7 3 81 89 97 1 05 1 13 1 21 12 9 13 72 1 0 18 26 34 4 2 50 58 66 7 4 82 90 98 1 06 1 14 1 22 13 0 13 82 1 0 18 26 34 4 2 50 58 66 7 4 82 90 98 1 06 1 14 1 22 13 0 13 8
2 1 0 18 26 34 4 2 50 58 66 7 4 82 90 98 1 06 1 14 1 22 13 0 13 82 1 0 18 26 34 4 2 50 58 66 7 4 82 90 98 1 06 1 14 1 22 13 0 13 8
3 1 1 19 27 35 4 3 51 59 67 7 5 83 91 99 1 07 1 15 1 23 13 1 13 93 1 1 19 27 35 4 3 51 59 67 7 5 83 91 99 1 07 1 15 1 23 13 1 13 93 1 1 19 27 35 4 3 51 59 67 7 5 83 91 99 1 07 1 15 1 23 13 1 13 9
3 1 1 19 27 35 4 3 51 59 67 7 5 83 91 99 1 07 1 15 1 23 13 1 13 94 1 2 20 28 36 4 4 52 60 68 7 6 84 92 100 1 08 1 16 1 24 13 2 14 0
4 1 2 20 28 36 4 4 52 60 68 7 6 84 92 100 1 08 1 16 1 24 13 2 14 04 1 2 20 28 36 4 4 52 60 68 7 6 84 92 100 1 08 1 16 1 24 13 2 14 04 1 2 20 28 36 4 4 52 60 68 7 6 84 92 100 1 08 1 16 1 24 13 2 14 0
5 1 3 21 29 37 4 5 53 61 69 7 7 85 93 101 1 09 1 17 1 25 13 3 14 15 1 3 21 29 37 4 5 53 61 69 7 7 85 93 101 1 09 1 17 1 25 13 3 14 1
5 1 3 21 29 37 4 5 53 61 69 7 7 85 93 101 1 09 1 17 1 25 13 3 14 15 1 3 21 29 37 4 5 53 61 69 7 7 85 93 101 1 09 1 17 1 25 13 3 14 16 1 4 22 30 38 4 6 54 62 70 7 8 86 94 102 1 10 1 18 1 26 13 4 14 2
6 1 4 22 30 38 4 6 54 62 70 7 8 86 94 102 1 10 1 18 1 26 13 4 14 26 1 4 22 30 38 4 6 54 62 70 7 8 86 94 102 1 10 1 18 1 26 13 4 14 2
6 1 4 22 30 38 4 6 54 62 70 7 8 86 94 102 1 10 1 18 1 26 13 4 14 27 1 5 23 31 39 4 7 55 63 71 7 9 87 95 103 1 11 1 19 1 27 13 5 14 37 1 5 23 31 39 4 7 55 63 71 7 9 87 95 103 1 11 1 19 1 27 13 5 14 3
7 1 5 23 31 39 4 7 55 63 71 7 9 87 95 103 1 11 1 19 1 27 13 5 14 37 1 5 23 31 39 4 7 55 63 71 7 9 87 95 103 1 11 1 19 1 27 13 5 14 3
8 1 6 24 32 40 4 8 56 64 72 8 0 88 96 104 1 12 1 20 1 28 13 6 14 48 1 6 24 32 40 4 8 56 64 72 8 0 88 96 104 1 12 1 20 1 28 13 6 14 48 1 6 24 32 40 4 8 56 64 72 8 0 88 96 104 1 12 1 20 1 28 13 6 14 4
8 1 6 24 32 40 4 8 56 64 72 8 0 88 96 104 1 12 1 20 1 28 13 6 14 4
Power Control Groups(2400 and 3600 bps)
1 17 33 49 65 81 97 113 129 145 161 177 193 209 225 241 257 273 2 18 34 50 66 82 98 114 130 146 162 178 194 210 226 242 258 274
1 17 33 49 65 81 97 113 129 145 161 177 193 209 225 241 257 273 2 18 34 50 66 82 98 114 130 146 162 178 194 210 226 242 258 274
1 17 33 49 65 81 97 113 129 145 161 177 193 209 225 241 257 273 2 18 34 50 66 82 98 114 130 146 162 178 194 210 226 242 258 274 1 17 33 49 65 81 97 113 129 145 161 177 193 209 225 241 257 273
2 18 34 50 66 82 98 114 130 146 162 178 194 210 226 242 258 274 3 19 35 51 67 83 99 115 131 147 163 179 195 211 227 243 259 275
4 20 36 52 68 84 100 116 132 148 164 180 196 212 228 244 260 276 3 19 35 51 67 83 99 115 131 147 163 179 195 211 227 243 259 275 4 20 36 52 68 84 100 116 132 148 164 180 196 212 228 244 260 276
3 19 35 51 67 83 99 115 131 147 163 179 195 211 227 243 259 275 4 20 36 52 68 84 100 116 132 148 164 180 196 212 228 244 260 276
3 19 35 51 67 83 99 115 131 147 163 179 195 211 227 243 259 275 4 20 36 52 68 84 100 116 132 148 164 180 196 212 228 244 260 276 5 21 37 53 69 85 101 117 133 149 165 181 197 213 229 245 261 277
6 22 38 54 70 86 102 118 134 150 166 182 198 214 230 246 262 278 5 21 37 53 69 85 101 117 133 149 165 181 197 213 229 245 261 277
6 22 38 54 70 86 102 118 134 150 166 182 198 214 230 246 262 278 5 21 37 53 69 85 101 117 133 149 165 181 197 213 229 245 261 277 6 22 38 54 70 86 102 118 134 150 166 182 198 214 230 246 262 278
5 21 37 53 69 85 101 117 133 149 165 181 197 213 229 245 261 277 6 22 38 54 70 86 102 118 134 150 166 182 198 214 230 246 262 278
7 23 39 55 71 87 103 119 135 151 167 183 199 215 231 247 263 279 8 24 40 56 72 88 104 120 136 152 168 184 200 216 232 248 264 280 7 23 39 55 71 87 103 119 135 151 167 183 199 215 231 247 263 279
8 24 40 56 72 88 104 120 136 152 168 184 200 216 232 248 264 280 7 23 39 55 71 87 103 119 135 151 167 183 199 215 231 247 263 279
8 24 40 56 72 88 104 120 136 152 168 184 200 216 232 248 264 280 7 23 39 55 71 87 103 119 135 151 167 183 199 215 231 247 263 279 8 24 40 56 72 88 104 120 136 152 168 184 200 216 232 248 264 280
1 5 9 13 17 21 25 29 33 37 41 45 49 53 5 7 6 1 65 691 5 9 13 17 21 25 29 33 37 41 45 49 53 5 7 6 1 65 69
1 5 9 13 17 21 25 29 33 37 41 45 49 53 5 7 6 1 65 691 5 9 13 17 21 25 29 33 37 41 45 49 53 5 7 6 1 65 69
1 5 9 13 17 21 25 29 33 37 41 45 49 53 5 7 6 1 65 691 5 9 13 17 21 25 29 33 37 41 45 49 53 5 7 6 1 65 691 5 9 13 17 21 25 29 33 37 41 45 49 53 5 7 6 1 65 69
1 5 9 13 17 21 25 29 33 37 41 45 49 53 5 7 6 1 65 692 6 1 0 14 18 22 26 30 34 38 42 46 50 54 5 8 6 2 66 70
2 6 1 0 14 18 22 26 30 34 38 42 46 50 54 5 8 6 2 66 702 6 1 0 14 18 22 26 30 34 38 42 46 50 54 5 8 6 2 66 702 6 1 0 14 18 22 26 30 34 38 42 46 50 54 5 8 6 2 66 70
2 6 1 0 14 18 22 26 30 34 38 42 46 50 54 5 8 6 2 66 702 6 1 0 14 18 22 26 30 34 38 42 46 50 54 5 8 6 2 66 70
2 6 1 0 14 18 22 26 30 34 38 42 46 50 54 5 8 6 2 66 702 6 1 0 14 18 22 26 30 34 38 42 46 50 54 5 8 6 2 66 703 7 1 1 15 19 23 27 31 35 39 43 47 51 55 5 9 6 3 67 71
3 7 1 1 15 19 23 27 31 35 39 43 47 51 55 5 9 6 3 67 713 7 1 1 15 19 23 27 31 35 39 43 47 51 55 5 9 6 3 67 71
3 7 1 1 15 19 23 27 31 35 39 43 47 51 55 5 9 6 3 67 713 7 1 1 15 19 23 27 31 35 39 43 47 51 55 5 9 6 3 67 713 7 1 1 15 19 23 27 31 35 39 43 47 51 55 5 9 6 3 67 71
3 7 1 1 15 19 23 27 31 35 39 43 47 51 55 5 9 6 3 67 713 7 1 1 15 19 23 27 31 35 39 43 47 51 55 5 9 6 3 67 71
4 8 1 2 16 20 24 28 32 36 40 44 48 52 56 6 0 6 4 68 724 8 1 2 16 20 24 28 32 36 40 44 48 52 56 6 0 6 4 68 724 8 1 2 16 20 24 28 32 36 40 44 48 52 56 6 0 6 4 68 72
4 8 1 2 16 20 24 28 32 36 40 44 48 52 56 6 0 6 4 68 724 8 1 2 16 20 24 28 32 36 40 44 48 52 56 6 0 6 4 68 72
4 8 1 2 16 20 24 28 32 36 40 44 48 52 56 6 0 6 4 68 724 8 1 2 16 20 24 28 32 36 40 44 48 52 56 6 0 6 4 68 724 8 1 2 16 20 24 28 32 36 40 44 48 52 56 6 0 6 4 68 72
R E A D
WRITE
Reverse Traffic Channel Block Interleaving(1200 and 1800 bps)
Power Control Groups(1200 and 1800 bps)
1 17 33 49 65 81 97 113 129 145 161 177 193 209 225 241 257 273
2 18 34 50 66 82 98 114 130 146 162 178 194 210 226 242 258 274 1 17 33 49 65 81 97 113 129 145 161 177 193 209 225 241 257 273
2 18 34 50 66 82 98 114 130 146 162 178 194 210 226 242 258 274 1 17 33 49 65 81 97 113 129 145 161 177 193 209 225 241 257 273 2 18 34 50 66 82 98 114 130 146 162 178 194 210 226 242 258 274
1 17 33 49 65 81 97 113 129 145 161 177 193 209 225 241 257 273 2 18 34 50 66 82 98 114 130 146 162 178 194 210 226 242 258 274
1 17 33 49 65 81 97 113 129 145 161 177 193 209 225 241 257 273 2 18 34 50 66 82 98 114 130 146 162 178 194 210 226 242 258 274 1 17 33 49 65 81 97 113 129 145 161 177 193 209 225 241 257 273
2 18 34 50 66 82 98 114 130 146 162 178 194 210 226 242 258 274 1 17 33 49 65 81 97 113 129 145 161 177 193 209 225 241 257 273
2 18 34 50 66 82 98 114 130 146 162 178 194 210 226 242 258 274 1 17 33 49 65 81 97 113 129 145 161 177 193 209 225 241 257 273 2 18 34 50 66 82 98 114 130 146 162 178 194 210 226 242 258 274
3 19 35 51 67 83 99 115 131 147 163 179 195 211 227 243 259 275 4 20 36 52 68 84 100 116 132 148 164 180 196 212 228 244 260 276
3 19 35 51 67 83 99 115 131 147 163 179 195 211 227 243 259 275 4 20 36 52 68 84 100 116 132 148 164 180 196 212 228 244 260 276 3 19 35 51 67 83 99 115 131 147 163 179 195 211 227 243 259 275
4 20 36 52 68 84 100 116 132 148 164 180 196 212 228 244 260 276 3 19 35 51 67 83 99 115 131 147 163 179 195 211 227 243 259 275
4 20 36 52 68 84 100 116 132 148 164 180 196 212 228 244 260 276 3 19 35 51 67 83 99 115 131 147 163 179 195 211 227 243 259 275 4 20 36 52 68 84 100 116 132 148 164 180 196 212 228 244 260 276
3 19 35 51 67 83 99 115 131 147 163 179 195 211 227 243 259 275 4 20 36 52 68 84 100 116 132 148 164 180 196 212 228 244 260 276
3 19 35 51 67 83 99 115 131 147 163 179 195 211 227 243 259 275 4 20 36 52 68 84 100 116 132 148 164 180 196 212 228 244 260 276 3 19 35 51 67 83 99 115 131 147 163 179 195 211 227 243 259 275
4 20 36 52 68 84 100 116 132 148 164 180 196 212 228 244 260 276
n Results in variable rate transmission
n Repeated symbols are deleted Output stream of interleaver is gated with a time
filter Gate duty cycle varies with the transmit data rate
n A pseudorandom masking pattern masks duplicate data generated by the code symbol repetition
PCM Voice
ConvolutionalEncoding
Code SymbolRepetition
BlockInterleaving
VocoderProcessing
Baseband Traff ic to RF Section
OrthogonalModulationData Burst
RandomizerDirect Sequence
SpreadingQuadratureSpreadingBasebandFiltering
1.2288McpsUser Address
MaskLong
Code PNGenerator
Data BurstRandomizer
307.2kcpsFrom
OrthogonalModulation
FrameData Rate
To DirectSequenceSpreading
Reverse Traffic Channel:Data Burst Randomizing
Data Burst Randomizing: How and Why
HOW?
n All symbols are transmitted at full rate power During “gate-off” periods, transmit power is reduced by at least
20dB Every code symbol inputted to the repetition process is
transmitted only once
WHY?
n Power control of the reverse link must be more tightly coupled
The base station receiver can more quickly determine symbol strength since it only has to integrate 36 symbols (1.25 ms) at a time (unlike in the forward link processing)
Quick determination allows for more accurate power control signals sent via power control bit puncturing technique on forward link (Reverse Closed Loop Power Control)
n Randomizing transmitted data provides the effect of dispersing in time the power received at the cell site from the mobile stations easier de-spreading can occur when fewer interfering signals
are present
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
1.25 ms = 1 power control group = 36 code symbols = 6 Walsh codes
20 ms = 16 power control group = 576 code symbols = 96 Walsh codes
Next-to-last power control group in previous frame
Long PN Code chips used to scramble the36 code symbols in that power control group
0010111 • • • 110101011011000101
1010101 • • • 110111010101001010
Last 14 bits
Previous Frame
Previous Frame
Previous Frame
Previous Frame
13 14 15
13 14 15
13 14 15
13 14 15
1 2
1 2
1 2
1 2
Next Frame
Next Frame
Next Frame
Next Frame
13 14 15
13 14 15
13 14 15
13 14 15
ONE FRAME
Power Control Groups
Data Burst Randomizing
10
10
14 13 12 11 10 9 8
10
10
10
10
Vocoding
Time
Conv.Encod. & Rep.
BlockInterleaving
Ortho.Mod.
Data B urst
Random
DirectSeq.
Spread.
OQPSK
20ms
THISFRAME
PREVIOUSFRAME
b0, b1, b2, ... b13
144 chips
14 chips
20 ms of L ong C ode Chips
11
12
13
15
20 ms = 16 x 36 x 4 = 2304 chips
576
144
16
NOW
Grou p # 0
Grou p # 1
Grou p # 2
Grou p # 3
Grou p # 4
Grou p # 5
Grou p # 6
Grou p # 7
Group #8
Group #9
Group #1 0
Group #1 1
Group #1 2
Group #1 3
Group #1 4
Group #1 5
Full Rate Gating (transmit all groups)
At full rate, all power control groups are transmitted.
1/2 Rate Gating (transmit 1 out of each 2 groups)
b0
Grou p # 0
Grou p # 1
= 0
= 1
b1
Grou p # 2
Grou p # 3
= 0
= 1
b2
Grou p # 4
Grou p # 5
= 0
= 1
b3
Grou p # 6
Grou p # 7
= 0
= 1
b4
Grou p # 8
Grou p # 9
= 0
= 1
b5
Grou p # 10
Grou p # 11
= 0
= 1
b6
Grou p # 12
Grou p # 13
= 0
= 1
b7
Grou p # 14
Grou p # 15
= 0
= 1
One bit is required to select one out of two power control groups.At 1/2 rate, eight bits are used to select one out of each of the eight pairs of power control groups independently.
b0
Grou p # 0
Grou p # 1
= 0
= 1
b1
Grou p # 2
Grou p # 3
= 0
= 1
b2
Grou p # 4
Grou p # 5
= 0
= 1
b3
Grou p # 6
Grou p # 7
= 0
= 1
b8
= 0
= 1
b9
= 0
= 1
b4
Grou p # 8
Grou p # 9
= 0
= 1
b5
Grou p # 10
Grou p # 11
= 0
= 1
b6
Grou p # 12
Grou p # 13
= 0
= 1
b7
Grou p # 14
Grou p # 15
= 0
= 1
b10
= 0
= 1
b11
= 0
= 1
1/4 Rate Gating (transmit 1 out of each 4 groups)
b0
Gro up # 0
Gro up # 1
= 0
= 1
b1
Gro up # 2
Gro up # 3
= 0
= 1
b2
Gro up # 4
Gro up # 5
= 0
= 1
b3
Gro up # 6
Gro up # 7
= 0
= 1
b8
= 0
= 1
b9
= 0
= 1
b12
= 0
= 1
b4
Gro up # 8
Gro up # 9
= 0
= 1
b5
Gro up # 10
Gro up # 11
= 0
= 1
b6
Gro up # 12
Gro up # 13
= 0
= 1
b7
Gro up # 14
Gro up # 15
= 0
= 1
b10
= 0
= 1
b11
= 0
= 1
b13
= 0
= 1
1/8 Rate Gating (transmit 1 out of each 8 groups)
b0
b1
b2
b3
b4
b5
b6
b7
b8
b9 b
10 b
11 b
12 b
13
=0 =1
b0
=0 =1
b1
=0 =1
b2
=0 =1
b3
=0 =1
b4
=0 =1
b5
=0 =1
b6
=0 =1
b7
=0 =1
b8
=0 =1
b9
=0 =1
b10
=0 =1
b11
=0 =1
b12
=0=1
b13
0 1 3 4 5 6 7 8 9 10 11 12 13 14 152
4800 &7200 bps
2400 &3600 bps
1200 &1800 bps
La st 14 bits o f th e long PN
co de that we re use d to scramb le th e ne xt- to-la st
p ower con tro l group of the p re vio us fram e
n 9600 & 14400 bps – transmit all power groups
n 4800 & 7200 bps – transmit selected power groups based on bits 0-7
n 2400 & 3600 bps – transmit selected power groups based on bits 0-11
n 1200 & 1800 bps – transmit selected power groups based on bits 0-13
Rates and Gating
RECV.
SEND
RECV.
SEND
1 .25 ms
0. 35m s
0.9 0 m s
0. 175ms
BASE STATION
MOBILE STATION
t
t
Worst case scenario: The mobile station is at the borderof the base station (430/2 chips = 32.6 mi = 0.175 ms)
1
2
3
4
“Valid” Power Control Commands
n The channel is spread by a pilot PN sequence with a zero offset
n Baseband f iltering ensures that the waveform is contained within the required frequency limits
n Baseband signals converted to radio frequency (RF) in the 800 MHz or 1900 MHz range
PCM Voice
Baseband Traffic to RF Section
Convoluti ona l
Encoding
Code S ymbol
Re pe tition
B lockInte rlea ving
Vocoder
Proces sing
Orthogona lModulation
Data Bur st
Randomizer
D irec t S eque nce
Spreading
Qua drature
Spreading
Base ba ndFilteri ng
1 .228 8Mc ps
I-Channel Pilot PN Sequence1 .22 88 Mcps
PN
I
Q
I
Q
P N c hip
1.2 288 Mc ps
From
Data BurstRandomizer
RF Conve rte rs
D
1/ 2 PN ChipTime De lay
Bas ebandFi lte r
Bas eband
Fi lte r
cos(2fct)
sin(2fct)
Reverse Traffic Channel:Direct Sequence Spreading
n The channel is spread by a pilot PN sequence with a zero offset
n Baseband f iltering ensures that the waveform is contained within the required frequency limits
n Baseband signals converted to radio frequency (RF) in the 800 MHz or 1900 MHz range
PCM Voice
Baseband Traffic to RF Section
Convoluti ona l
Encoding
Code S ymbol
Re pe tit ion
B lockInte rlea ving
Vocoder
Proces sing
Orthogona lModulation
D ata Bur st
R andomizer
D irec t S eque nce
Spreading
Qua drature
Spreading
B ase ba ndFilteri ng
1 .228 8Mc ps
I-C hannel Pilot PN Sequence1 .22 88 Mcps
PN
I
Q
I
Q
P N c hip
1.2 288 Mc ps
From
D ata BurstR andomizer
R F C onve rte rs
D
1/ 2 PN C hipTime De lay
B as ebandFi lte r
B as eband
Fi lte r
cos(2fct)
sin(2fct )
Reverse Traffic Channel:Offset Quadrature Spreading & Baseband Filtering
I
Q
-•/4
•/4
-3•/4
3•/4
(0,0)
(1,1)
(1,0)
(0,1)
I
Q
t
t
1/ 2 chip
0 0 /4
1 0 3 /4
1 1 -3 /4
0 1 - /4
I Q Ph ase
By introducing a half-chip delay in the “Q”,
simultaneous transitions of “I” and “Q” are
eliminated.
An amplifier that does not have to deal with diagonal changes of state is simpler and cheaper to implement!
Why Bother?
Reverse Traffic Channel:Why a Half Chip Delay in the Q Component?
Reverse Channel Demodulation
n IS-95A/J-STD-008 requires a process that is complementary to the mobile station modulation process
n CDMA processing benefits from multipath components Signals from several receive elements can be combined to
improve receive signal quality
U/DCommand
De-InterleaverSpeechOutputCombiner
BTS Receiver BSC
DemodulatorSearch
Correlator
DemodulatorSearch
Correlator
DemodulatorSearch
Correlator
DemodulatorSearch
Correlator
Power Cont rol De ci sion
ViterbiDecoder
Vocoder