A Non-Coherent Multi-Band IR-UWB HDR Transceiver based on Energy Detection

A Non-Coherent Multi-Band IR-UWB A Non-Coherent Multi-Band IR-UWB HDR Transceiver based on Energy HDR Transceiver based on Energy

DetectionDetection

Mohamad MrouéMohamad Mroué,, Sylvain Haese, Ghaïs El-Zein, Sylvain Haese, Ghaïs El-Zein,

Stéphane Mallegol and Stéphane PaqueletStéphane Mallegol and Stéphane Paquelet

17th IEEE International Conference on Electronics, Circuits and Systems

December 15th, 2010

Athens, Greece

Mohamad Mroué 17th IEEE ICECS 2010 December 15th, 2010 2

Presentation progressPresentation progress

1.1. MB IR-UWB Transceiver for HDR Applications MB IR-UWB Transceiver for HDR Applications (Modulation Principles and Architecture)(Modulation Principles and Architecture)

2.2. Analog CMOS Pulse Energy Detector Analog CMOS Pulse Energy Detector (Architecture (Architecture and Performance)and Performance)

3.3. Conclusion and ProspectsConclusion and Prospects







Impulse radio based solution duplicated on multiple sub-bandsImpulse radio based solution duplicated on multiple sub-bands

• Asynchronous treatment at reception based on energy detection– Amplitude modulation: Amplitude modulation: On-Off KeyingOn-Off Keying (OOK) (OOK)

– Non-coherent demodulation: energetic threshold comparisonNon-coherent demodulation: energetic threshold comparison

• To avoid inter-symbol interference: the pulse repetition period Tr must be greater than the channel delay spread Td

• Extension to multiple bands: to increase the system capacity

… 1 1 0 1 …

1 0 11

… 1 1 0 1 …

Tr

Td

Pulse generator

OOK modulation

Band-pass filter

Pulse detector

ADC

Channel

(S. Paquelet et al., in joint UWBST IWUWBS, 2004)(S. Paquelet et al., in joint UWBST IWUWBS, 2004)

Principles of the proposed system Principles of the proposed system High data rate transmission with impulse radio High data rate transmission with impulse radio ??


Transmitter architecture: filter bank implementationTransmitter architecture: filter bank implementation

3.1GHz 10.6GHz

3.1GHz 10.6GHz

1

1

0

0

0

1

Receiver architecture: pulse detector on each sub-bandReceiver architecture: pulse detector on each sub-band

3.1GHz 10.6GHz

3.1GHz 10.6GHz3.1GHz 10.6GHz

1

1

0

0

0

1

3.1GHz 10.6GHz

UWB HDR transceiver architectureUWB HDR transceiver architecture

Measured transmission responses versus frequency for a 3.1-5.2 GHz octoplexer.

(De)multiplexer involved in the MB-(De)multiplexer involved in the MB-OOK UWB transceiverOOK UWB transceiver

– No power division effect In-band insertion loss < 4 dB

– No external bias (Only passive devices)

– Identical (de)multiplexer for Tx and Rx

Advantages of the proposed architecture:Advantages of the proposed architecture:– Relaxed hardware constraints:

• Only coarse synchronization is needed

• Energy based processing

– Flexibility of the multi-band architecture:• Scalable data rate / power control

• Radio resource management

n 16 to 24

Bi 250 to 500 MHz

Ti 10 to 100 ns

Tr > 25 ns

Throughput

(3 meters)

> 600 Mbps


UWB HDR transceiver architectureUWB HDR transceiver architecture

Transceiver’s componentsTransceiver’s components– Commercial monocycle pulse generator

• Peak-to-peak amplitude into 50 Ω load: 3.29 V• Duration: 184 ps, center frequency: 5 GHz

– Quadriplexer (3.1-4.2 GHz)• (De)multiplexer only based on filters• Identical (de)multiplexer for Tx and Rx

• No external bias (Only passive devices)

• No power division effect No need of signal

amplification (In-band insertion loss < 3 dB)• Mechanical etching process using low-cost

organic substrate (RO3010)

– Amplification stages• Total amplification level of 42 dB

– UWB antennas

• Conical monopole (Omni-directional)

• Horn antenna (Directional with half power beamwidth > 50° in the 3.1-4.2 GHz) 2.75 3.00 3.25 3.50 3.75 4.00 4.25 4.50 4.752.50 5.00

-70

-60

-50

-40

-30

-20

-10

-80

0

Frequency (GHz)

Tra

nsm

issio

n (

dB

)

Readout

m2

Readout

m1

m1Frequency: 3.16 GHz|S21| = -2.441 dB


S21 S31 S41 S51


Measurement results in LOS and NLOS configurationsMeasurement results in LOS and NLOS configurations

Directional Antennas

Omni-directional Antennas

Configuration

(Tx to Rx)

Omni. to Omni.

Omni. to Direct.

Direct. to Direct.

3-dB Bandwith 250 MHz

Number of sub-bands 24

Range (m) 1 3 1 3 1 3

Average delay spread (ns)

17.2 34.0 9.6 16.8 8.15 11.2

Pulse repetition period (ns)

20 40 10 20 10 15

Data rate (Gbps) 1.2 0.6 2.4 1.2 2.4 1.6




2.2. Analog CMOS Pulse Energy DetectorAnalog CMOS Pulse Energy Detector (Architecture (Architecture and Performance)and Performance)



Specifications:Specifications:• Operation with large bandwidth (3.1-10.6 GHz)

– Input detector bandwidth ~ 500 MHzInput detector bandwidth ~ 500 MHz

• Low mass fabrication cost

• Low power consumption and low complexity – The circuit must provide the pulse detection on each sub-bandThe circuit must provide the pulse detection on each sub-band

CMOS technology

Implementation study of the detectorImplementation study of the detector


Squarer based on two MOSFETs Squarer based on two MOSFETs – When biased with zero drain to source voltage in the triode region

– The circuit is driven by balanced signals

– Output current:

– Condition :• M1 and M2 must perfectly be matched (K, a1, a2)

– Avantages :• Simple design

• No additional power consumption

• Principle can be applied on all CMOS IC technologies

Adopted squarer circuitAdopted squarer circuit


IntegratorIntegrator

IntegratorIntegrator– Current to voltage conversion and integration

directly around a capacitor

– Current amplifier: • Low input impedance: square law operation of the first stage

• High output impedance: integration and S/H stage


IampIin

Current amplifierCurrent amplifier

– Input bandwidth ~ 500 MHz• Useful part of the squared signal pass to the

integrator unaffected

– Architecture based on current mirrors • Easy to implement

• Reduced complexity

• Low voltage and low power consumption


– Output capacitor• Current to voltage conversion

• Signal integration



Adopted architecture: open loop S/H circuitAdopted architecture: open loop S/H circuit

– Charge injection effects Sampling errors

• Charge injection compensation: – CMOS switchCMOS switch

– Minimum-geometry switches Minimum-geometry switches

– Large capacitorLarge capacitor

– Switch architecture

• Reset switch: low ON resistance rON

– Short discharge time for the hold capacitor Short discharge time for the hold capacitor

• Other switches: minimum (W,L) – reduce the charge injection effectsreduce the charge injection effects

– Output stage

• Unity gain output buffer– High input impedanceHigh input impedance

Sample and hold circuitSample and hold circuit


Noise performanceNoise performance– Noise level at the output of the detector

• Included detector parts: squarer, current amplifier, switch (ON state) and the hold capacitor

• Estimated noise level: ~ 1 % of the useful signal level

Imperfection effects studyImperfection effects study– Effect of the input impedance of the current amplifier on the squarer

• Gain variation of the squarer as a function of the input impedance

Effects of the MOS transistors’ parameters variationsEffects of the MOS transistors’ parameters variations– Squarer operation:

• Effect on the gain of this stage

• The square law function of the squarer is not affected

– Current amplifier operation: Current offset and gain

• A modification of the architecture permit to reduce the generated offset current

Circuit performanceCircuit performance


Time domain simulationTime domain simulation– Simulator: CADENCE Spectre

– Technology : AMS 0.35 μm BiCMOS

Pulse detector architecturePulse detector architecture

Circuit parameters

Squarer

(W/L)N 40/0.35 VG 1 V

Current amplifier

(W/L)N 7.2/0.35 Bandwidth at 3dB 563 MHz

(W/L)P 70/0.35 VDD = - VSS 1.8 V

Ibias 84.5 μA Power consumption 0.6 mW

Output stage

I0 240 μA Bandwidth at 3dB 825 MHz

VDD = - VSS 1.8 V Power consumption 1.6 mW


Pulse Energy Detector with two parallel stages for the integrator and S/H stages. Pulse Energy Detector with two parallel stages for the integrator and S/H stages.

– Time domain simulation• Simulator: CADENCE Spectre

• Technology : AMS 0.35 μm BiCMOS

• Tr = 15 ns, Ti = 13 ns, TReset = 3 ns , Ts = 8 ns

Pulse detector architecturePulse detector architecture

Input pulseIntegrationSamplingReset

1 0 1 1 0 1 Transmitted code:







ConclusionConclusion– Functional tests of the communicating system in real environment

– Comparison between the use of directional and Omni-directional antennas in LOS and NLOS configurations

– Implementation evaluation of the proposed Multi-band IR-UWB system

MB IR-UWB receiver architecture MB IR-UWB receiver architecture

Conclusion and prospectsConclusion and prospects

Base-band: pulse energy detectionPower consumption: ~ 40 mW

Analog Front-End: LNA and VGA with an appropriate technologyPower consumption: ~100 mW

Filter bank: no additional power consumption

LTCC technology(Low Temperature Co-fired Ceramic)

SiP approach (System in Package)

CMOS Technology


Thank you for your attention !Thank you for your attention !


ITE-UWB HDRITE-UWB HDR Principles Performances: optimal demodulation rule

Energy demodulation problem for OOK (one sub - band)

two symmetric hypothesis

Objective : minimise error probability knowing and after estimating

20 0

21 0

H : [ ( )]

H : [ ( ) ( )]

i

i

T

T

x w t dt

x s t w t dt

2

0, ( ) ,

iT

iT E s t dt NB

0 ( )p y

1( )p yy

Optimal threshold opt

N

1.4

opt LM M L

N

0 1opt optp pN N

L

L

with

Special demodulation threshold

1

2

1

0

1 1

( ) , 0( )

( ) 2 , 0

M

M y

y LM

y ep y y

M

yp y e I yL y

L

2 2 1i

xy NEL N

M BT

Probability densities

où

S. Paquelet, L-M. Aubert et al, UWBST 2004,

« An Impulse Radio Non-coherent Transceiver for High Data Rates »


E/N (dB)

Pe

Coherent - RAKE receiver: Energy recovered on few paths

whereas

Quadratic integration: Whole available energy recovered

rake achieves comparable if it collects 33% to 40% of the whole available energy.

Extended Notion of OFDM orthogonal carrier orthogonal pulses intrinsic fading resistance

eP

S. Paquelet, L-M. Aubert et al, UWBST 2004, « An Impulse Radio Non-coherent Transceiver for High Data Rates »

R * 150 240 600 Mbit/sd 10 5 3 mB 500 500 250 MHzNband 12 12 24Tr 80 50 40 ns

CM 4 3 2Ti 50 40 30 ns

Pe * 10-5 10-5 10-5

CM: IEEE Channel Models- 2: NLOS 0-4 meters- 3: NLOS 4-10 meters- 4: Extreme NLOS multipaths

* without FEC

ITE-UWB HDRITE-UWB HDR Principles Performances/Comparisons


Mean performance for a given received energy when Mean performance for a given received energy when considering the FCC limitationsconsidering the FCC limitations


Quadriplexer (3.1-4.2 GHz)Quadriplexer (3.1-4.2 GHz)

Mechanical etching processMechanical etching process Low cost organic substrate RO3010Low cost organic substrate RO3010

– « Ceramic-filled PTFE composite »

– Dielectric constant : 10.2

– Metallization thickness : 17 µm

ArchitectureArchitecture– 1 Low pass filter

– 4 bandpass filters

• Based on resonators

No power division effectNo power division effect

(S. Mallégol et al., EuRAD&EuMC, 2006)(S. Mallégol et al., EuRAD&EuMC, 2006)

Sub-band (GHz)

Central Frequency (Fc, GHz)

Insertion loss at Fc (dB)

Bandwidth at 3 dB (MHz)

Bandwidth at 10 dB

(MHz)

3.1-3.22 3.151 2.68 185.8 308.4

3.44-3.55 3.495 2.23 199.8 295.3

3.79-3.91 3.834 2.33 196.2 309.4

4.13-4.25 4.193 2.43 193.3 322.2 2.75 3.00 3.25 3.50 3.75 4.00 4.25 4.50 4.752.50 5.00

-70

-60

-50

-40

-30

-20

-10

-80

0

Frequency (GHz)

Tra

nsm

issio

n (

dB

)

Readout

m2

Readout

m1



S21 S31 S41 S51

Intercept-point magnitude betweenadjacent sub-bands > 14 dB


Octoplexer (3.1-5.1 GHz)Octoplexer (3.1-5.1 GHz)

ANR BILBAO ProjectANR BILBAO Project

Size: 71 mm 62 mm

In

2.75

3.00

3.25

3.50

3.75

4.00

4.25

4.50

4.75

5.00

5.25

5.50

5.75

6.00

6.25

2.50

6.50

-110

-100

-90

-80

-70

-60

-50

-40

-30

-20

-10

-120

0

Frequency (GHz)

Tra

nsm

issi

on (

dB)

Readout

m1

Readout

m2

Readout

m3

m1freq=dB(S(1,2))=-2.561

3.180GHzm2freq=dB(S(1,5))=-3.166

4.240GHzm3freq=dB(S(1,9))=-3.078

5.760GHz

(S. Mallégol et al., EuRAD&EuMC, 2006)(S. Mallégol et al., EuRAD&EuMC, 2006)


Monocycle-pulse

generator

3.1-5.2 GHz Octoplexer

G0

iT

2(.)

G0

iT

2(.)



Out1

Out8

Measurements results

CADENCE simulation results

Time domain

Frequency domain

1 GHz/div

1 V/div

1 ns/div

Time domain

Frequency domain

1 GHz/div

1 V/div

1 ns/div

Non-filtered monocycle pulse

Into 50 :Vpeak-to-peak = 3.29 VDuration = 184 ps

200 mV/div

2 ns/div

3.1-3.22 GHz filter

3.79-3.91 GHz filter



200 mV/div

2 ns/div

3.1-3.22 GHz filter




The first 4 pulses at the outputs of the 3.1 – 5.2 GHz octoplexer (Tx)

Spread of the output pulses < 6 ns (< Td)

Measurements and simulation resultsMeasurements and simulation results

LNA


Objective: to reduce current offset level generated at the outputObjective: to reduce current offset level generated at the output

– Modifying the architecture of the current amplifier

– Altering the positions of two p-channel and n-channel MOS transistors Compensation of effects of MOS transistors’ parameters variations

The current offset is reduced by 4 to 5 times

Modified current amplifier architectureModified current amplifier architecture


Evaluation of the current offset variation generated at the output of the current Evaluation of the current offset variation generated at the output of the current amplifieramplifier

• Variation of the threshold voltage VT and the transconductance factor K

– Comparison between analytical and simulation results

Variation effects of MOS transistors’ Variation effects of MOS transistors’ parametersparameters


New Monte-Carlo simulation results using CADENCE with variations on mismatch New Monte-Carlo simulation results using CADENCE with variations on mismatch and both mismatch and process parametersand both mismatch and process parameters

Modified current amplifier architectureModified current amplifier architecture

mismatch mismatch & process

Documents

A Non-Coherent Multi-Band IR-UWB HDR Transceiver based on Energy Detection