MOBAT – MICOMMOBAT – MICOMThe best radio for worst events

Increasing Data ThroughputIncreasing Data Throughput Over HF links

Hana Rafi - CEO

Eder Yehuda - VP R&D

1

Traditional HF RadioTraditional HF Radio

- Analog voice & 50,75…bpsg , p

New Trends on HF

- Digital voice, Noise reduction…

- High Data Rate …19200…bpsQAM

High linearity, SNR ,Efficiency

2

Requirements from the New HF RadioRequirements from the New HF RadioFor HDR performance

-Linearity - ISI

High dyn range

-High efficiency

Small size-High dyn. range

-Low ACI & IBN

-Small size.

-High MTBFLow ACI & IBN

-High Power TX.

High MTBF.

-feasible.

3

HPA andHPA andHigh Data Rate (HDR)

Traditional TX Inter-Mod : 31dBHDR RX SNR Requirements : >33 dBq

PSD

31dBSNR

~30dB

Frequency

4

q y

micom Radiomicom Radio &HPA Solution

Linearized Power Amplifier :N MICOM C

TX PWR 125/175W 125W Availability

New MICOM Spec.

Current Spec. Achivments

TX PWR 125/175W… 125W AvailabilityInter-Mod >42 dB 30-32dB Data RateEffi i 45% 30% EEfficiency >45% 30% EnergyPWR con. 280 /390W 416W Size

5

Efficiency V.S. PAR

(Peak to Average Ratio)

efficiencyPower density CPFSKyprobability

nPSK

F K

nQAM

Power level0dbm5dbm

6

0dbm-5dbm

New HF Generation & New HF Generation & iimicommicom

HDR Road-MapHDR Road Map• n*ISB Radio, 125/175W and HPA

• HDR Modems 9600,19200…64K bps

• Enhanced STD-5066 email gateway (IP)

• Enhanced digital voice• Enhanced digital voice

7

Technical session onLinearized techniques & Achievements on

micom – radiomicom radio

Mr Yehuda EderMr. Yehuda Eder

Thank you , have a productive day

8

Problem descriptionob e desc p o

LinearPout

Non Linearity caused by:

• PA/transmitter linearization

PinPSD

• RGC – Receiver Gain Control• TGC/ALC – Transmitter Gain Control• D/A-A/D – Resolutions

L l O ill h i

ACIBBN

• Local Oscillators phase noise • Receiver/Transmitter BW• Group Delay Variation

Freq

BBN

ISIIBN

9

Freq.

Available SolutionsAvailable Solutions

Linear Power Transceiver :Linear Power Transceiver :

Linear Power Amplifier, Class-A or A/B with large backoff :Low efficiency high costLow efficiency, high cost

AGC, TGC,ALC : HELD (Input regulation based on average signal level should be held) )HF channel receive signal variations may cause problems to the receiver performance and the linearity.

Linearized Power Amplifier High Efficiency and IMD

10

RGC – Receiver Gain ControlTGC/ALC Transmitter Gain ControlTGC/ALC–Transmitter Gain Control

Special techniques for attack-release of p qGAIN CONTROL must be used.

GAIN

T > delta between 2 peaks

Data AGC

GAIN

Typical AGC

TIME

11

A/D –D/A Quantizing NoiseA/D D/A Quantizing Noise

Distortion & Noise in CODECs•Integral non-linearity•Differential non-linearity.•Total Harmonic Distortion (THD)Total Harmonic Distortion (THD).•Total Harmonic Distortion Plus Noise (THD+N)•Signal to Noise and Distortion Ratio (SINAD, or S/N+D).•Effective Number Of Bits (ENOB).( )•Signal to Noise Ratio (SNR).•Analog Bandwidth (Full Power, Small Signal)•Spurious Free Dynamic Range (SFDR).•Two Tone Inter-modulation Distortion.•Noise Power Ratio (NPR).

12

Local/Synthesizer Oscillators phase noisey p

The synthesizer is the source of:yIBNBBN

Hi h iHigh noise near the carrier =

SNR degradation

13

Receiver/Transmitter BW

In band ripple

Group delay variances

14

PA characteristics - linear scalePA characteristics linear scale

15

“Typical” class AB PA characteristicsTypical class AB PA characteristics (measurements)

Power Gain Phase Transfer FunctionPower Gain Phase Transfer Function

16

PA linearity vs SNRPA linearity vs. SNR

MIL-STD188-141B Requirement: Intermodulation distortion (IMD).Intermodulation distortion (IMD).The IMD products of HF transmitters produced by any two equal-level signals within the 3 dB bandwidth shall be at least 30 dB below either tone for fixed station application, and 24 dB below either tone for tactical application.

The 24/30dB limits the SNR performance.

Summary Performance tests results: SNR IMD (below tone)

3445

3339

3133

2830

2424 2424

1920

1819

17

the IMD should be improved for better SNR

PA Linearization TechniquesPA Linearization Techniques

Power Amplifier Linearization Techniques:p q• Feed Forward • Pre-Distortion • EER – Envelope Elimination RestorationEER Envelope Elimination Restoration • Cartesian Feedback

O hOur approach: High Efficiency Class-AB amplifier with Cartesian Feedback & EER to achieve high linearity and high efficiency.

18

Linearization TechniquesFeed-forward

Linearization Techniques

Vi VoP. A.G1 1 21 1 2

Error

1G2 2

Amplifier

- High complexity- Wide BW - Low freq Range

19

- Low freq. Range

pre-distortionLinearization Techniquespre-distortion

Vo

F(*)linear

Vi

VoP. A.Vi iV

Predistorter

iV

Vm

F(Vm)

- High complexityVi Vm

High complexity- Wide BW - Low freq. Range

20

Digital adaptive pre-distortionLinearization Technique

Digital adaptive pre distortion

V oF (V m )

P . A .

D / A D / A

I \ QM o d .

L . O .

P o la r to C a r te s ia n

D / A D / A

Var. A

t

P re -d is to r tio nc a lc u la tio n

P h i(k T s)

I(k T s ) Q (k T s )P re d is to r te dA d a p tiv e

P re d is to r t io n

tt.

Adress

D a t a

L o o k -u p ta b leC a r te s ianto P o la r

I /Q (k T s )

A m p (k T )

A d a p ta tio n a lg o rith m

(A i,P h ii) n e w(A i,P h i i) o ld

\T a b le s

A m p (k T s)

I \ QD e m o d .

A / D

D o w nC o n v e r te r

I/Q (k T s )D e m o d u ta te d

21

D ig ita l e le m e n tsR F / a n a lo g e le m e n ts

Linearization TechniqueDigital Pre-distortion - Preliminary Results

Linearization Technique

22

EER (Envelope Elimination and Restoration)

Envelopemodulator

VDD

)(cos)( tttVtV ci VoP. A.Signal

separation

)(1 tVtS

)(cos2 tttS c

-High Efficiency

- limited performance

23

PA without AM- –AM loopto PMIpol=[-95 0 87 0] ; Qpol=0

PA Ch t i ti T T I t d l ti AM l

10

15

20

Gai

n

PA Characteristics

20

40Two Tone Intermodulation. - AM loop

green - Sourceblue - PAred - PA with linearizer

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.80

5

Vin [Volt]

200

-20

0

Am

p [d

B]

-100

0

100

200

Pha

se [o ]

-60

-40

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8-200

100

Vin [Volt]

200 210 220 230 240 250 260 270 280 290 300-80

IM3 = 25 dBcAM loop improvement > 20 dB

24

AM loop improvement > 20 dB

PA with AM-to-PM ( 0 ÷ 25° ) – AM loopIpol=[-95 0 87 0] ; Qpol=[-75 0 0 0]

10

15

20

Gai

n

PA Characteristics

20

40Two Tone Intermodulation. - AM loop

green - Sourceblue - PAred - PA with linearizer

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.80

5

Vin [Volt]

G

180-20

0

mp

[dB

]

160

170

180

Pha

se [o ]

-60

-40A

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8150

Vin [Volt] 200 210 220 230 240 250 260 270 280 290 300-80

IM3 = 25 dBcAM loop improvement =0 dB

25

For QAM modulation Cartesian loop is required

Analog Cartesian Loop - Block Diagramg p g

RF Out

Snom= 43 dBm

Smax= 50 dBm ; Smin= 30 dBm

Nmax= - 104 dBm / Hz

Closed loop, Narrowband (< 200 kHz)

AMPAMP Directional

CouplerLPFP Adigitalatten.15 dB

digitalatten.15 dB

L.O I/QModulator

-20 dB(17 dBm mixer)

(Syn)AMP

- 2 dB

AMP

SLO= 10 +/- 2 dBm

coup.(10dB)

splitter-6 dB

IREF

loop filter

loop filter

err_I

err_Q

+

+

-

I_Tx Q_Tx

QREF

FPGAD / A

D / A

LPF

LPF

I_TsQ_Ts

fs

12

12 RF components

I_dem Q_dematten.4 B

-

Offset andI / Q balance

compensation circuits

s pAnalog componentsDigital components

I/Q DeMod.digitalatten.15 dB

atten.10 dB

atten.5 dB

(17 dBm mixer)AMP

26

Analog Cartesian Loop Performance

27

Micom Linearization solution EER & Cartesian loopEER & Cartesian loop

DCP.S.

LPF

Envelope

LPF28 / 48 VDC

110 VAC (option)

PIN =1 WattSignal Processing

Unit

P A

Harmonicfilter

PTX =500 Watt

Phase modulated RF

RF modulated-to-Polar

Cartesian Linearization(complex closed loop)

Unit

DC feedback

Att.

28

Micom – Radio implementation

DCP.S.

LPFReconst.

Envelope followerDigital

BB

DSP/

Var.Att. P A

14

12

Exc.D/A

S

IF1=1.05 MHzDigital

IF

BPFBPF

Bi-directionalIF amp.

1.6 - 30MHz

Harmonicfilter

IF2 = 45.1 MHz

Tx. ALC(fine + course)

BW= 12.1 KHz

FPGA

BW= 12.1 KHzIF2 = 1.05 MHz

Synt. Synt. Att.

Att.

Finj=46.15 MHz Finj=46.7 - 75.1 MHzstep=1.25 KHz step=8.75 KHz

fs= 20 MHz

R AGCPre-

LNA

BPF

Finj=430.77 kHz

BPFLPF

Digital

BW= 400 KHzanti-alias IF2= 45.1 MHz

IF1=5 MHz

Rec. AGC Sel.

Var.Att.

Var.Att.

BPF

anti-aliasBW= 3 KHzIF2 = 20 kHz

14

A/DIF Tx. ALC Tx. ALC(course)(fine + course)

29

fs=20 MHz

Micom – Digital part implementation DSP/FPGA

Envelopefollower

LPF

14 Digital BB

Envelopegenerator

Cartesian feedbackSSB

d

ALE

ITx(kT)Iref(kT)

BPF

fs= 4 - 5 MHz

14IF=4.5 - 5 MHz

Digital IF

fs= 15 - 20 MHz

14

codecAudioAmp.

I/Qmod.

NCO

Freq.compensation

Loopfilter

Errordetector

mod.vocoder

Tx

QTx(kT)Qref(kT)

Datamodem

Data sourcesanti-alias

codecAudioAmp.

Audiosources

BPF

BPF

TGC

TGC

Phasegen.

NCO(/PLL)

Ifbck(kT) Qfbck(kT)

Data

Data targets

LPFcodecAudio

circ.

REF clk

14

Digital IFLPF

reconstruction

codecAudiocirc. I/Q

demod.vocoder

ALE

SSBdemod.

BPF Noiseblanker

Audiotargets

Datamodem AGCreconstruction

IF1= 4.5 - 5 MHzf 4 0 5 MH

AudiopowerAmp. CPU

Multiport RS232USB port

Ethernet portMMI

AGCIF2= 20 kHz

fs1=4.0 - 5 MHz

fs2=100 - 200 kHz

30

USB port MMIH/W control

Micom simulation results

40Two Tone Intermodulation. - Complex loop

Micom simulation results

0

20

green - Sourceblue - PAred - PA with linearizer

-40

-20

Am

p [d

B]

200 210 220 230 240 250 260 270 280 290 300-80

-60

200 210 220 230 240 250 260 270 280 290 300

IM3 = 20 dBcComplex loop improvement ~ 25 dB

31

Two complex tones - baseband spectrumTwo complex tones baseband spectrumf1 = -30 Hz, f2 = 25 Hz

32

Two complex tones - I/Q plotp Q p)2sin()2sin()( 21 tfatfatI

)2/2sin()2/2sin()( 21 tfatfatQ

33

Single tone (modulating signal) I/Q plotSingle tone (modulating signal) I/Q plot

34

Non-Linear PA

35

Micom Simulation

36

Linearized PALinearized PA

37

Single tone time waveforms (RF or modulating signal)

38

I/Q plotQ p

39

Micom Short and Long term solutions

40

Thank you

41

micommicom HDR-ISB coco SSystem Solution

micom – 2*ISB Radio 125/175W

d f 500 4000 Wready for 500-4000 W

micom MD 9600/19200micom – MD-9600/19200

STD-5066 email gateway g yJITC @ Q1-Q2 2005

42