ece 145b / 218b, notes set 1: radio architectures ... · introduction to receiver frequency plans....
TRANSCRIPT
class notes, M. Rodwell, copyrighted 2012
ECE 145B / 218B, notes set 1: Radio Architectures & Modulation Formats
Mark Rodwell
University of California, Santa Barbara
[email protected] 805-893-3244, 805-893-3262 fax
class notes, M. Rodwell, copyrighted 2012
Material Covered Last Term: 145a / 218a
.amplifierspower on toIntroducti
noise on toIntroducti
designsamplifier tunedReactively
gains.Power
analysisgain graphs flow Signal
ChartsSmith and tuningImpedance
ddistribute and lumped :designamplifier Broadband
radiation modes, loss, :lineion transmissReal
linesion transmissIdeal
elements passive ideal vs.Real
class notes, M. Rodwell, copyrighted 2012
145b / 218b Outline (1)
productsation intermodul ,recieiversin Distortion
,interceptsorder -3rd andorder -2nd
distortionation intermodul and Harmonic n.descriptio seriespower :distortion Weak
products distortion of Generation
plans.frequency receiver on toIntroducti
ceInterferen ChannelAdjacent response. imageReceiver
receiversin coversion Frequency
Mixers s.frequencie difference and sum tion,multiplica signal
tions.representa plane signal I/Q
functions. g.y with triefficientl ing work
I conversionFrequency
diagramsblock ceiver trans
recievers. odynesuperheter and TRF :resarchitectureceiver
(FM) digital, QAM DSB, & AM :formats modulation
modulation-de and modulation:conversionfrequency for need
signals coded-digitally voice,analog of spectra
spectrum radio available
receivers and ers transmittRadio
class notes, M. Rodwell, copyrighted 2012
145b / 218b Outline (2)
synthesisfrequency and loopslock Phase
sOscillator
balnus ers, transform trees,:combiningpower
efficiency power, maximum classes,amplifier loadlines,
amplifiersPower
designLNA tuned-reactively
analysis noisecircuit models, noise math, :noise
amplifiers noise-Low
tiesnonlineari and responses image
unbalanced and balanced active, & passive
level)-(circuitdesign Mixer
range dynamicreceiver y,sensitivitreceiver
IP3. aggregate floor, noise aggregate
onsdistributigain and plansfrequency
designsReceiver
class notes, M. Rodwell, copyrighted 2012
Radio Waves,
Propagation,
and Antennas
class notes, M. Rodwell, copyrighted 2012
The Radio Spectrum
109
1010
1011
1012
1013
1014
1015
Frequency (Hz)
microwave
SHF*
3-30 GHz
10-1 cm
mm-wave
EHF*
30-300 GHz
10-1 mm
optic
al
385-7
90 T
Hz
sub-mm-wave
THF*
0.3-3THz
1-0.1 mm
far-IR: 0.3-6 THz
near-IR
100
-385
TH
z
3-0
.78
m
mid-IR
6-100 THz
50-3 m
104
105
106
107
108
109
1010
Frequency (Hz)
MF*
0.3-3 MHz
1000-100 m
HF*
3-30 MHz
100-10 m
VHF*
30-300 MHz
10-1 m
UHF*
0.3-3 GHz
1 m-10 cm
microwave
SHF*
3-30 GHz
10-1 cm
10-1
100
101
102
103
104
Wavelength (meters)
10-6
10-5
10-4
10-3
10-2
10-1
Wavelength (meters)
*ITU band designations ** IR bands as per ISO 20473
class notes, M. Rodwell, copyrighted 2012
Frequencies of a Few Services (Rough #s)
109
1010
1011
1012
1013
1014
1015
Frequency (Hz)
radar sate
llite T
V
sate
llite lin
ks
wire
less H
DM
I
imag
ing
104
105
106
107
108
109
1010
Frequency (Hz)
AM
rad
io
FM
rad
io
TV
TV
cell phones
WiFi
10-1
100
101
102
103
104
Wavelength (meters)
10-6
10-5
10-4
10-3
10-2
10-1
Wavelength (meters)
class notes, M. Rodwell, copyrighted 2012
Choice of Transmission Frequency
earth theof Curvature
beam. blocking of Ease
size. antenna Required
bad. and weather good :nattenuatio cAtmospheri
.allocationfrequency Government
class notes, M. Rodwell, copyrighted 2012
Atmospheric Attenuation in Bad Weather
very heavy fog
Liebe, Manabe, Hufford, IEEE Trans Antennas and Propagation, Dec. 1989
propagation in bad weather favors use of frequencies below ~10 GHz
rain
heavy rain
tropical deluge
Olsen, Rogers, Hodge, IEEE Trans Antennas & Propagation Mar 1978
Hurricane
class notes, M. Rodwell, copyrighted 2012
Curvature of the earth, reflection from the ionosphere
earth. theof curvature by the limited
ision transmissradio range-Long
ion transmissrange-long enables
ionosphere thefrom Reflection
ionosphere in the MHz 10order of
frequency, resonance plasmaelectron the
below sfrequencie requires This
(Marconi) carriersfrequency -lowor
satellites requires radio nentalInterconti
class notes, M. Rodwell, copyrighted 2012
Fresnel Zone: Where the Radio Beam Carriers The Signal
Zone.Fresnel (first) thecalled is This
.2/ areaan in carried is antennasbetween beam The
2/
2/2/2/
)()2/1()2/1(
)(/1/1)(
and assume usLet
.4/)(
.4/ than less is lengthspath in difference if phase-in (almost) add Paths
1
2
1
1
2
2
2
1
2
21
2
2
2
2
2
1
2
1
21
2
2
2
2
2
1
2
121
22
1
22
1
121
21
22
1
22
1
RHA
RH
RHRHRH
RRRHRRHR
RRRHRRHRRRHRHR
RHRR
RRHRHR
class notes, M. Rodwell, copyrighted 2012
Fresnel Zone: Where the Radio Beam Carries The Signal
blocked. be likely to less are
signals frequency)-(lowerelength Longer wav
beam. in thepower theofmost block will
.2/ area hence 2/ diameter ofobject an
, and assuming Still
11
121
RARH
RHRR
class notes, M. Rodwell, copyrighted 2012
Nearly Isotropic Antennas
/2~ islenght y when effectivel radiates :antenna Dipole
antenna" wave-quarter"
plane. ground wideusingby
length in 1:2 reduced becan Antenna
plane lin vertica )cos(~ as variesand
plane, lin vertica isotropic ispattern radiation
http://en.wikipedia.org/wiki/File:Elem-doub-rad-pat-pers.jpg
class notes, M. Rodwell, copyrighted 2012
Directional Antennas
Uda-Yagi
http://en.wikipedia.org/wiki/File:Two_meter_yagi.jpg http://en.wikipedia.org/wiki/Log-periodic_antenna
http://en.wikipedia.org/wiki/File:SuperDISH121.jpg
periodic-log
reflector
parabolic
patternradiation
ofplot Typical
http://en.wikipedia.org/wiki/Radiation_pattern
class notes, M. Rodwell, copyrighted 2012
Antenna Directivity
antenna isotropic ofintensity radiated
radiatedintensity peak ydirectivit
http://en.wikipedia.org/wiki/Radiation_pattern
steradiansin angle) (solidbeamwidth angular
4
steradiansin angle) (solidbeamwidth angular
sphere a of angle solidydirectivit
1.64. ofy directivit a have antennas dipole wave-half Simple
class notes, M. Rodwell, copyrighted 2012
Friis Transmission Formula
Rrt
dtransmitte
received eR
DD
P
P
16 2
2
2
nattenuatio catmospheri
rangeion transmiss
ydirectivit antenna
R
D
n...propagatiomultipath
path beam in the objects
planet theof curvature
terrainfrom scattering
:factorsmany Ignores
class notes, M. Rodwell, copyrighted 2012
Signals to be
Transmitted
class notes, M. Rodwell, copyrighted 2012
Signals we might want to transmit by radio
kb/s 320-32 :audio compressed MP3
Mb/s 100 ~ :WiFi
Mb/s 15about : HDTV Compressed
Gb/sec 1.5about :HDTV edUncompress
20kHz-20Hz :c)(optimisti hearinghuman of Range
kHz 4-0.4 :ion transmisssoundquality -Voice
waves.radioby them transmit toare weif
frequency in d translatebemust signals These
class notes, M. Rodwell, copyrighted 2012
Generation of Digital Data Streams
.resolution bits of # some with digitized bemust then Samples
n.compressioby reduced becan rates data
,redundancy contains stream digital theIf
on theory)(informati
MP3,... MPG, JPG,
class notes, M. Rodwell, copyrighted 2012
Recall the Sampling Theorem
.2 rate aat sampled bemust ),( to
limitedbandwidth of signal a aliasing, spectral avoid To
. sigsamplesigsig ffff
image shifted by +fsample image shifted by -fsample
class notes, M. Rodwell, copyrighted 2012
Bandlimiting of digital data streams (1)
bandwidth signal thereduces and waveform
therounds signal digital a Filtering
spectrumflat a has impules ofA train
)2//()2/sin( spectrum
has train pulser rectangulaA
bitbit
class notes, M. Rodwell, copyrighted 2012
Bandlimiting of digital data streams (2)
),2/1,2/1(bandwidth
tofiltered wall-brick is stream data theIf
bitbit ff
)./()//sin( shape a has pulse dataeach then bitbit tt
stream. data in the bits sucessivebetween
(ISI) ceinterferen lintersymbo zero is thereso
.,etc,4,3,2for zero
is )/()//sin(function The
bitbitbit
bitbit
t
tt
class notes, M. Rodwell, copyrighted 2012
Bandlimiting of digital data streams (3)
draw. tohard is This pulses. theseof
sum a is waveformdigital Overall
like. looks waveform what theis Here
sequences. data possible allfor
repeatedly draw is Trajectory
pattern. eyean is This
class notes, M. Rodwell, copyrighted 2012
Bandlimiting of digital data streams (4)
zero. be willceinterferen lintersymbo then the
point, indicated about theration degree 180 a with symmetric is spectrum theIf
rate.bit the(1/2) -/an greater thsomewhat bandwidth required typical
broader, are filters Typical
rate.bit the(1/2) -/ the toequal isbandwidth totalminimum
)2/1,2/1( isbandwidth Minimum
bitbit
: theorem)sampling his (NOT theoremsideband vestigalsNyquist'
class notes, M. Rodwell, copyrighted 2012
Pulses with Raised Cosine Spectra : From Wikipedia.
pulse of TransformFourier
systemsion transmissreal ingapproximatin used are These signals. ISI-zero offamily a of
onidealizati almathematic a is waveformpulse cosine- Raised The
http://en.wikipedia.org/wiki/Raised-cosine_filter
pulse of waveformTime
1.for , ),( i.e. )/1,/1( to
, 0for , )2/,2/( i.e. , )2/1,2/1( from vary will
signal digital baseband theof rangefrequency the1, to0 from varies As
bitbitbitbit
bitbitbitbit
ff
ff
class notes, M. Rodwell, copyrighted 2012
Pulses with Raised Cosine Spectra: Filters
)2/sin(/2)/()(function transfer havemust (#2)filter channel
thespectrum, /2)/()2/sin( a hasalready pulser rectangula a Since
.)( spectrum cosine-raised thehavemust which *pulse filtered* theisIt
bitbit
bitbit
fH
fH
hardware. realin present not isfilter first theso
impulses,not pulses,r rectangula produce circuits digital real course, Of
class notes, M. Rodwell, copyrighted 2012
Root Raised Cosine Spectra in Transmission Links
noise.receiver limit toas soreceiver thebandlimit further must We
band.frequency allowed n thestay withi er to transmittthebandlimit must welink, radio aIn
filters. *cosine-raised-root* using edaccomplish is This
criterion.Nyquist meet must ISI; zero have alsomust signal received final The
class notes, M. Rodwell, copyrighted 2012
Root Raised Cosine Spectra in Transmission Links
)2/sin(/)2/()()(/)()(
:is responsefilter er transmitt thepulses,r rectangulaby driven isit Given that
)()(
:responsefrequency cosine-raised-root have alsomust then filter receive The
)()(
:signal ed transmittfor the spectrum *cosine-raised-root* a Choose
)()(
:function cosine-raised a is )(
2
3
bitbitRCrectTF
RCF
RCT
RCfiltered
filtered
jHjHjHjH
jHjH
jHjH
jHjH
jH
class notes, M. Rodwell, copyrighted 2012
Modulation and
Frequency Conversion
class notes, M. Rodwell, copyrighted 2012
Frequency Conversion / Modulation
ation).(multiplic mixingby done isit ;modulation called is This
carrier.frequency -high on the signalour imposemust we this,do To
105
106
107
108
109
1010
1011
Frequency (Hz)
).-(DC to)2/-(DCbetween spectrum baseband a has stream data the,on Depending bitbit ff
GHz. 100 toMHz few perhapsbetween sfrequencie radio using signal the transmit We
class notes, M. Rodwell, copyrighted 2012
Mixing = Multiplication
)cos()( tVtV BIB
)cos()( tVtV LOLOLO
0/)cos()cos()( VtVtVtV LOLOBIRF
tt
eeeeeeee
eeeeeeee
zzzzzzzz
zzzztt
zzeet
zzeet
BLOBLO
tjtjtjtjtjtjtjtj
tjtjtjtjtjtjtjtj
LOBLOBBLOLOB
LOLOBBLOB
LOLO
tjtj
LO
BB
tjtj
B
LOBBLOLOBLOB
LOBLOBBLOLOB
LOLO
BB
)(cos2)(cos2
)()(
))(()cos()cos(4
so
)cos(2
)cos(2
11111111
1111
11
11
y.efficientl functions trig. work withlearn tomust We
)sin(2 and )cos(2)sin()cos( jjjjj eejeeje
class notes, M. Rodwell, copyrighted 2012
Mixing = Multiplication
)cos()( tVtV BIB
)cos()( tVtV LOLOLO
sfrequencie difference and sum
generatestion Multiplica
tVVVtVVV
VtVtVtV
BLORFIBLORFI
LORFBIRF
)(cos)2/()(cos)2/(
/)cos()cos()(
00
0
)sin()( tVtV BQB
)cos()( tVtV LOLOLO
tVVVtVVV
VtVtVtV
BLOLOQBLOLOQ
LOLOBQRF
)(sin)2/()(sin)2/(
/)cos()sin()(
00
0
n...calculatiosimilar aBy
class notes, M. Rodwell, copyrighted 2012
Mixing → Convolution of Spectra
)(tVB
)(tVLO
0/)()()( VtVtVtV LObRF
)'()'()'(2
1
2
)( and )( ofn convolutio
2
)(*)()(
0
00
jdjjVjVV
V
jVjV
V
jVjVjV
LOb
LObLObRF
)()()()()( So
)(2 that Recall
)2/()2/()cos()( Suppose
LOLOLOLOLO
LO
tj
tj
LO
tj
LOLOLOLO
VVjV
e
eVeVtVtV
LO
LOLO
Spectrum of the Local Oscillator
class notes, M. Rodwell, copyrighted 2012
Mixing with cosine ("I") local oscillator
)(tVB
spectrum oscillator Local
)( jVRF
parts)imaginary real, (note
spectrum signal Baseband
)cos()( Suppose tVtV LOLOLO
spectrum signal RF
class notes, M. Rodwell, copyrighted 2012
Mixing with sine ("Q") local oscillator
)(tVB
spectrum oscillator Local
)( jVRF
parts)imaginary real, (note
spectrum signal Baseband
)sin()( Suppose tVtV LOLOLO
)()()()()( LOLOLOLOLO VjVjjV
sidebands) theof phase flipped the(note
spectrum signal RF
class notes, M. Rodwell, copyrighted 2012
IQ Modulation
)(, tV IB
)(, tV QB
)sin()()cos()(
)sin()(
)cos()(
)(0
,
0
,
ttVttV
tV
VtVt
V
VtVtV
LOQLOI
LO
LOQB
LO
LOIB
RF
)cos( tV LOLO
)sin( tV LOLO
streams data edsynchroniz t,independen are )( and )( ,, tVtV QBIB
class notes, M. Rodwell, copyrighted 2012
IQ Signal Representation
)sin()()cos()()()(Re)( ttVttVetjVtVtV LOQLOI
tj
QIRFLO
plane ain point a as drepresente is Signal
class notes, M. Rodwell, copyrighted 2012
IQ Signal Representation
)sin()()cos()()( ttVttVtV LOQLOIRF
wavecosine wavesine
)cos( tLO)cos( ttLO
frequency angular
at clockwise-counter spins
class notes, M. Rodwell, copyrighted 2012
Quadrature Phase Shift Keying (QPSK)
)(, tV IB
)(, tV QB
)sin()()cos()(
)sin()(
)cos()(
)(0
,
0
,
ttVttV
tV
VtVt
V
VtVtV
LOQLOI
LO
LOQB
LO
LOIB
RF
)cos( tV LOLO
)sin( tV LOLO
sequencesbinary are )( and )( ,, tVtV QBIB
QAM-4 as often) (lessknown Also
class notes, M. Rodwell, copyrighted 2012
16-Quadrature Amplitude Modulation (16-QAM)
etc. QAM,-256 QAM,-64 also is There
)cos( tV LOLO
)sin( tV LOLO
class notes, M. Rodwell, copyrighted 2012
Demodulation
)cos( tV LOLO )cos( tV LOLO
)sin( tV LOLO )sin( tV LOLO
)(, tV IB
)(, tV qb
)(tVri
)(tVrq)(tVS
)sin()()cos()()( 0,0, tVVtVtVVtVtV LOLOQBLOLOIBS
)2sin()()2cos(2)(2)(
)cos()sin()()(cos)(
)cos()()(
2
0,
2
0
2
,
2
0
2
,
2
0,
22
0,
0
tVVtVtVVtVVVtV
ttVVtVtVVtV
tVVtVtV
LOLOQBLOLOIBLOIB
LOLOLOQBLOLOIB
LOLOSri
LPFby removed
.2at term2)()( Similarly, LO
2
0
2
, VVtVtV LOQBrq
class notes, M. Rodwell, copyrighted 2012
Receiver Tuning
class notes, M. Rodwell, copyrighted 2012
Early (1910's) Receiver: Tuned Radio Frequency
tuning.during filters multiple of trackingMechanical :Problem
bandwidth. uningnarrower t filters cascaded Multiple
stations separate tobandwidth a broad toohas isfilter LC singleA
class notes, M. Rodwell, copyrighted 2012
Superheterodyne Receiver (Amstrong, 1918)
selection. channelfor used are filters IF tuned-fixed Sharp
frequency. LO theby varying tunedis frequency signal Received
detection. before
frequency teintermediaan toconverted is signal radio Receive
class notes, M. Rodwell, copyrighted 2012
Overall Block Diagrams
class notes, M. Rodwell, copyrighted 2012
QAM/QPSK reciever
odyneSuperheter
conversionDirect
recovery data
andclock to
class notes, M. Rodwell, copyrighted 2012
QAM/QPSK Transmitter
odyneSuperheter
conversionDirect
class notes, M. Rodwell, copyrighted 2012
What are the design issues ?
designamplifier Power
synthesisfrequency and PLLs
noise phase design,
sOscillator
ondistributigain receiver plans,frequency receiver
inteceptsorder - third
responses Spurious
filtersnecessary responses, image mixers, ofoperation
conversionFrequency
noise totalblock,each ofon contributi noise
ysensitivitReceiver