o
6
13
57
2
4
Omni Cell planning
6
13
57
2
4
120 Sectorization
63
57
2
41
60 Sectorization
o
810
1
7
2
3
4
9
6
12
5
11
Tricell planning: (Most (Most Common)Common)
No. of cells in the cluster can be divided by 3
Tricell planning
D1 D2D3
C3 C2C1
A3 A2A1
B3 B2B1 D1 D2
D3
C3 C2C1
A3 A2A1
B3 B2B1
D1 D2D3
C3 C2C1
A3 A2A1
B3 B2B1 D1 D2
D3
C3 C2C1
A3 A2A1
B3 B2B1
D1 D2D3
C3 C2C1
A3 A2A1
B3 B2B1
D1 D2D3
C3 C2C1
A3 A2A1
B3 B2B1
D1 D2D3
C3 C2C1
A3 A2A1
B3 B2B1
D1 D2D3
C3 C2C1
A3 A2A1
B3 B2B1
))/(3
1log(10/ RDIC
Prob.1 Construct 4 Walsh (Orthogonal) codes for 4
different users by two methods. Assume that 4 users transmit their data with 22Kbps (before spreading) using these codes such that:
User 1 transmits +1 @ 500m User 2 transmits -1 @ 1000m User 3 transmits -1 @ 1200m User 4 transmits -1 @ 1500m Carrier Freq.=3GHz Path Loss Factor=2.
a) For downlink transmission, Construct the transmitted and decoded (de-spread) signals for the 4 users. Assuming users 1,2,3&4 see the following attenuation L1X, L2X, L3X and L4X; where Li is the path loss factor with (n=2) plus the following Noise Level; U1: +0.5p, U2: -1p, U3: +0.5p, U4:+1p. Find the decoded signals and calculate the average bit error rate based on X. Given that 0<X<1.
c) X is the attenuation factor due to the shadowing effect with Standard deviation =32dB, Find the bit error rate (BER).
d) If X has Rayleigh Fading distribution instead of the shadowing effect, Find the bit error rate (BER).
e) Find the Average Duration of fade in Case (d) for 100km/hr vehicle.
1-aW1=0 W2= 0 0 0 1
-1 -1 -1 -1-1 1 -1 1-1 -1 1 1-1 1 1 -1
-1 -1 -1 -1-1 1 -1 1-1 -1 1 1-1 1 1 -1
-1 -1 -1 -1-1 1 -1 1-1 -1 1 1-1 1 1 -1
1 1 1 11 -1 1 -11 1 -1 -11 -1 -1 1
W0=0000W1=0101W2=0011W3=0110
W4= 0 0 0 0 0 1 0 1 0 0 1 1 0 1 1 0
W8=
*L1*X
1-a Wireless Channel
U1
U2
U3
Data
Data
Data
U4
TransmittedSignal (Air)
-1 -1 -1 -1
-1 1 -1 1
-1 -1 1 1
1 1 1 1
-1 -1 -1 -1
-1 -1 -1 -1
-1 -1 -1 -1
-1 -1 -1 -1
1 -1 1 -1
1 1 -1 -1
1 -1 -1 1
2 -2 -2 -2
Transmitter
(2 -2 -2 -2)*L1*X
-1 1 1 -1
(2 -2 -2 -2)*L2*X
(2 -2 -2 -2)*L3*X
(2 -2 -2 -2)*L4*X
*L2*X
*L3*X
*L4*X
+0.5p
-1p
+0.5p
+1p
Added Noise@ Rx
(2 -2 -2 -2)*L1*X
(2 -2 -2 -2)*L2*X
(2 -2 -2 -2)*L3*X
(2 -2 -2 -2)*L4*X
(2L1X+0.5 -2L1X+0.5 -2L1X+0.5 -2L1X+0.5)
(2L2X-1 -2L2X-1 -2L2X-1 -2L2X-1)
-1 -1 -1 -1-1 -1 -1 -1
-1 1 -1 1-1 1 -1 1
-1 -1 1 1-1 -1 1 1
-1 1 1 -1-1 1 1 -1
(2L3X+0.5 -2L3X+0.5
-2L3X+0.5 -2L3X+0.5 )
(2L4X+1 -2L4X+1 -2L4X+1 -2L4X+1)
(-2L1X-0.5 +2L1X-0.5 +2L1X-0.5 +2L1X-0.5)
(-2L2X+1 -2L2X-1 +2L2X+1 -2L2X-1)
(-2L3X-0.5 +2L3X-0.5 -2L3X+0.5 -2L3X+0.5)
(-2L4X-1 -2L4X+1 -2L4X+1 +2L4X-1)
= +4L1X -2p “if ” >0 1
= -4L2X < 0 0
= -4L3X < 0 0
= -4L4X< 0 0
•L12=
pWattd
3.253))500*4)(10*3(
10*3()
)1*4(( 2
9
8
pWattd
3.63))1000*4)(10*3(
10*3()
)2*4(( 2
9
8
pWattd
9.43))1200*4)(10*3(
10*3()
)3*4(( 2
9
8
pWattd
14.28))1500*4)(10*3(
10*3()
)4*4(( 2
9
8
•L22=
•L3
2= •L4
2=
(-2L1X-0.5 +2L1X-0.5 +2L1X-0.5 +2L1X-0.5)
(-2L2X+1 -2L2X-1 +2L2X+1 -2L2X-1)
(-2L3X-0.5 +2L3X-0.5 -2L3X+0.5 -2L3X+0.5)
(-2L4X-1 -2L4X+1 -2L4X+1 +2L4X+1)
X is the attenuation factor due to the shadowing effect with Standard deviation =27.5dB, Find the bit error rate (BER).
= +4*253.3p X -2p if >0 1
= -4*63.3p X < 0 0
= -4*43.9p X < 0 0
= -4*28.14p X< 0 0
As 0<X (Attenuation) <1 is always positive;
= +4*253.3p X -2p (NOT always >0 User1 sent: 1)
= -4*63.3p X (always <0) User2 sent: 0
= -4*43.9p X (always <0) User3 sent: 0
= -4*28.14p X (always <0) User4 sent: 0
Probability of Correct decoding is:Probability that X > 1.974*(10^-3)So: Probability that Loss <1/( 1.974*(10^-3)) So: Power Loss < 1/( 1.974*(10^-3))^2 or Power Loss < 54 dB
c-If Rayleigh Fading is Considered
instead of the shadowing effect,
1212
12)10(
/
10*425.0*10*848.15
10*848.151)54.(Pr
1).(Pr24.5
2min
2
BER
eXob
eOutageob rmsrr
D-
)(
1).(Pr )/( 22min
thR
rr
rN
e
LCR
OutageADF
rms
778.277)10*3
6.3/100(*10*3
89
max f
sec10*716.510*771.2/10*84.15
10*771.2
*)10*98.3(*778.277*2)(
9312
3
10*84.156 12
ADF
erN thR
Autocorrelation (* then +)Pr.2
1 1 1 1 Result
1 1 1 1 0
1 1 1 1 1
1 1 1 1 2
1 1 1 1 3
1 1 1 1 4
1 1 1 1 3
1 1 1 1 2
1 1 1 1 1
1 1 1 1 0
Cross CorrelationPr.3
1 1 1 1 Result
1 -1 1 -1 0
1 -1 1 -1 -1
1 -1 1 -1 0
1 -1 1 -1 -1
1 -1 1 -1 0
1 -1 1 -1 1
1 -1 1 -1 0
1 -1 1 -1 1
1 -1 1 -1 0
Rake ReceiverIt’s a well known block for CDMA
receivers to eliminate multipath effect and increase SINR.
Functions: Channel delay estimation or
Impulse Response (IR)Measurement for multipath
componentsProvides a separate correlation
receiver for each of the multipath signals
Mobile Network Generations
1st Generation (1G):Many standardsAnalog System
voice services only No SIM card Limited Roaming
Examples in TableOther Standards:
AMPS (USA) –Bell labs 1970
NTT (Japan)
ARP NMT-900In Use 1971 1986
Frequency Band
150 MHz 900 MHz
Channels 80 400Modulation FM FM
Transmit Power
1 5W 100m, 1 and 6W
Handover in Call
No Yes
Country Finland SwitzerlandPower
Consumption high medium
22ndnd Generation Generation (2G):(2G):Digital Voice
NetworkSlow data rate
(Short Message Service -SMS)
Wider coverage compared to 1G
Roaming supportCircuit Switching
GSM 900 IS-95 PDC
In Use 1991 1993 1993
Frequency Band (Hz)
890960M 824 894M 810 1501M
Channels / carrier
8 64 codes 3
Access TDMA / FDMA
CDMA / FDMA
TDMA / FDMA
Transmit Power
Up to 1W 600 mW
Handover in Call
yes yes yes
Countries Europe 212 countries (70% world)
USA Japan
Channel rate 270.833 kbps 1,228.8 kbps 42 kbps
Voice / data rate
13 / 9.6 kbps 14.4 kbps 6.7 kbps
2.5G:2.5G:GSM GPRS (General packet radio service):
Released in 2001<= 171.2Kbps/carrierVoice Circuit switching, Data Packet switchingMedia Message Service (MMS)
IS-95 IS95BPDC PDC-Data
2.75G2.75G:GPRS EDGE (Enhanced Data GSM Evolution):
Released in 2003<= 473.6 kbps/carrierVoice Circuit switching, Data Packet switchingMMS and Internet access with better quality
3G:3G:WCDMA (Wideband CDMA) = UMTS (Universal Mobile
Telecommunications System):EuropeanCDMA/FDMA1885-2025 MHz (uplink) and 2110-2200 MHZ (downlink)384 kbps Urban outdoor2048 kbps Indoor and low range outdoorSoft Handover (handover with same carrier)accommodate QoS classes for four types of traffic:
Conversational class—Voice, video telephony, video gamingStreaming class— Multimedia, video on demand.Interactive class— Web browsing, network gaming,
database accessBackground class—E-mail, short message service (SMS), file
downloadingLocation Based services.
CDMA2000American
3.5G: UMTS-HSDPA (High Speed Downlink Packet Access) 2005/063.5G: UMTS-HSDPA (High Speed Downlink Packet Access) 2005/06Decreasing delay due to transmission errors Hybrid
Automatic Repeat Request.Decreasing Handover failure Fast cell site selection.Improving resources management Stand alone
downlink shared channelAdaptive Modulation and Coding. Download up to(14.4 Mbps and Upload up to 384
kbps) /sector. 3.75G: UMTS- HSUPA (High Speed Uplink Packet Access) 2007/083.75G: UMTS- HSUPA (High Speed Uplink Packet Access) 2007/08
DL: 14.400Mbps and UL: 5.8Mbps
4G: “in Research”4G: “in Research”Toward 100Mbps with IP core networkToward 100Mbps with IP core network
WiMAXLong Term Evolution (LTE)