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Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [ Implementation feasibility of SSA-UWB pulse wavelets (update) ] Date Submitted: [ January 14, 2004 ]
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Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [Implementation feasibility of SSA-UWB pulse wavelets (update) ] Date Submitted: [January 14, 2004] Source: [Honggang Zhang, Kamya Y. Yazdandoost, Kenichi Takizawa, Iwao Nishiyama, Keren Li, Yuko Rikuta, Tetsuya Yasui, Ryuji Kohno ] Company [ (1) Communications Research Laboratory (CRL), (2) CRL-UWB Consortium ] Connector’s Address [3-4, Hikarino-oka, Yokosuka, 239-0847, Japan] Voice:[+81-468-47-5101], FAX: [+81-468-47-5431], E-Mail: [honggang@crl.go.jp, yazdandoost@crl.go.jp, takizawa@crl.go.jp,nisiyama@crl.go.jp, keren@crl.go.jp, rikuta@crl.go.jp, t-yasui@crl.go.jp, kohno@crl.go.jp] Re: [IEEE P802.15 Alternative PHY Call For Proposals, IEEE P802.15-02/327r7] Abstract: [The implementation feasibility issues of optimized SSA-UWB pulse wavelets are investigated, considering the effects of Ultra Wideband antenna, quantization bits and sampling scheme. ] Purpose: [For analyzing the implementation feasibility of SSA-UWB pulse waveform shapes.] Notice: This document has been prepared to assist the IEEE P802.15. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein. Release: The contributor acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P802.15. CRL & CRL-UWB Consortium
Implementation Feasibility of SSA-UWB Pulse Wavelets (Update) Honggang ZHANG, K. Y. YAZDANDOOST, Kenichi TAKIZAWA, Iwao NISHIYAMA, Keren LI,Yuko RIKUTA, Tetsuya YASUI, Ryuji KOHNO Communications Research Laboratory (CRL) & CRL-UWB Consortium CRL & CRL-UWB Consortium
Major Contributors For This Proposal Update Honggang ZHANG Kamya Y. YAZDANDOOST Kenichi TAKIZAWA Iwao NISHIYAMA Keren LI Yuko RIKUTA Tetsuya YASUI Ryuji KOHNO CRL & CRL-UWB Consortium CRL & CRL-UWB Consortium CRL & CRL-UWB Consortium CRL & CRL-UWB Consortium CRL & CRL-UWB Consortium CRL & CRL-UWB Consortium CRL & CRL-UWB Consortium CRL & CRL-UWB Consortium CRL & CRL-UWB Consortium
Outline of presentation Summary of previously proposed SSA-UWB pulse wavelets Effects of quantization and sampling scheme on implementation issues of SSA-UWB pulse wavelets Using CRL’s SSA-UWB test-bed 3. Effects of two specific Ultra Wideband antennas on implementation issues of SSA-UWB pulse wavelets T-type antenna designed in CRL-UWB Consortium K-type antenna designed in CRL-UWB Consortium Conclusion remarks Backup materials CRL & CRL-UWB Consortium
GPS Band 3.1 10.6 1.99 1.61 0.96 1. Summary of previously proposed SSA-UWB pulse wavelets • Design a proper pulse wavelet with high frequency efficiency corresponding to any regulatory frequency mask. • Adjust transmitted signal’s spectra adaptively, so as to minimize interference with co-existing systems. SSA-UWB (Soft-Spectrum Adaptation) philosophy CRL & CRL-UWB Consortium
SSA-UWB for interference avoidance, global harmonization and compliance • Global harmonization and compliance is the everlasting aim and basic philosophy of CRL & CRL-UWB Consortium. • SSA-UWBscheme has a wide capability to be harmonized with all the present or future UWB systems and co-exist with various existing narrowband radio systems. • Just changing the kernel functions and shapes of SSA-UWB pulse wavelets to achieve smooth version-up. CRL & CRL-UWB Consortium
Features ofSSA-UWB • SSA-UWB with flexible pulse waveform and frequency band can be applied tosingle and multi-band/multi-carrier UWB by Free-verse typepulse waveform shapingand Geometrical typepulse waveform shaping, respectively. • Interference avoidanceforco-existence, harmonizationfor various systems,andglobal implementation can be realized. SSA-UWBcan flexibly adjust UWB signal spectrum so as to match with spectral restriction in transmission power, i.e. spectral masks in both cases ofsingleandmultiplebands. • Scalable, adaptive performance improvement. • Smooth system version-up similar to Software Defined Radio(SDR). CRL & CRL-UWB Consortium
SSA-UWB optimized pulse wavelet generation Spectrum characteristics of optimalSSA-UWB pulse wavelet 2 0 -10 1.5 -20 1 -30 0.5 -40 Relative amplitude Relative amplitude (dB) -50 0 -60 -0.5 -70 -1 -80 (3.12GHz) (5.8GHz) -1.5 -90 0 20 40 60 80 100 120 140 0 50 100 150 200 250 300 0.0ns 0.56ns 1.125ns 1.6875ns 2.25ns 2.8125ns 3.375ns 0.0GHz 3.47GHz 6.94GHz 10.41GHz 13.88GHz 17.35GHz Frequency (1 sample=69.4MHz) SSA-UWB pulse wavelet with adaptive spectral notches achieving coexistence, flexibility and efficient power transmission Time (128 samples=3.6 ns) CRL & CRL-UWB Consortium
Interference avoidance, global harmonization and compliance utilizing optimized SSA-UWB pulse wavelets Fixed Satellite Service 200MHz 200MHz Broadcast Auxiliary Service dBm/MHz 1GHz 3.1GHz 5.8GHz 10GHz CRL & CRL-UWB Consortium
2. Effects of quantization and sampling scheme on implementation issues of SSA-UWB pulse wavelets Based on CRL’s SSA-UWB test-bed CRL & CRL-UWB Consortium
2 1.5 1 0.5 Relative amplitude 0 -0.5 -1 -1.5 0 20 40 60 80 100 120 140 0.0ns 0.56ns 1.125ns 1.6875ns 2.25ns 2.8125ns 3.375ns Time (samples) MATLAB simulation of SSA-UWB pulse wavelet with various samples per pulse 2 1.5 1 0.5 Relative amplitude 0 -0.5 -1 -1.5 0 200 400 600 800 1000 1200 0.0ns 0.56ns 1.125ns 1.6875ns 2.25ns 2.8125ns 3.375ns Time (samples) SSA-UWB optimized pulse waveform generation (128 samples=3.6ns) SSA-UWB optimized pulse waveform generation (1024 samples=3.6ns) CRL & CRL-UWB Consortium
MATLAB simulation of SSA-UWB pulse wavelet with various quantization bits (2 and 3 bits) SSA-UWB optimized pulse waveform generation (1024 samples, 2bit) SSA-UWB optimized pulse waveform generation (1024 samples, 3bit) CRL & CRL-UWB Consortium
MATLAB simulation of SSA-UWB pulse wavelet with various quantization bits (2 and 3 bits) SSA-UWB optimized pulse waveform generation (1024 samples, 2bit) SSA-UWB optimized pulse waveform generation (1024 samples, 3bit) CRL & CRL-UWB Consortium
1 1 0.8 0.8 0.6 0.6 0.4 0.4 0.2 0.2 Relative amplitude Relative amplitude 0 0 -0.2 -0.2 -0.4 -0.4 -0.6 -0.6 -0.8 -0.8 -1 -1 0 200 400 600 800 1000 1200 0 200 400 600 800 1000 1200 0.0ns 0.56ns 1.125ns 1.6875ns 2.25ns 2.8125ns 3.375ns 0.0ns 0.56ns 1.125ns 1.6875ns 2.25ns 2.8125ns 3.375ns Time (samples) Time (samples) MATLAB simulation of SSA-UWB pulse wavelet with various quantization bits (4 and 6 bits) SSA-UWB optimized pulse waveform generation (1024 samples, 4bit) SSA-UWB optimized pulse waveform generation (1024 samples, 6bit) CRL & CRL-UWB Consortium
10 10 0 0 -10 -10 -20 -20 Relative amplitude (dB) Relative amplitude (dB) -30 -30 -40 -40 -50 -50 -60 -60 -70 -70 0 50 100 150 200 250 300 0 50 100 150 200 250 300 0.0GHz 3.47GHz 6.94GHz 10.41GHz 13.88GHz 17.35GHz 0.0GHz 3.47GHz 6.94GHz 10.41GHz 13.88GHz 17.35GHz Frequency (samples) Frequency (samples) MATLAB simulation of SSA-UWB pulse wavelet with various quantization bits (4 and 6 bits) Spectrum characteristics of SSA-UWB optimal pulse (1024 samples, 4bit) Spectrum characteristics of SSA-UWB optimal pulse (1024 samples, 6bit) CRL & CRL-UWB Consortium
1 1 Q 4 S A M P L E 1 2 8 Q 4 S A M P L E 2 5 6 0 . 7 5 0 . 7 5 0 . 5 0 . 5 0 . 2 5 0 . 2 5 e e d d u u t t i 0 l i 0 l p p m m A A - 0 . 2 5 - 0 . 2 5 - 0 . 5 - 0 . 5 - 0 . 7 5 - 0 . 7 5 - 1 - 1 - 2 . 7 - 1.8 - 0 . 9 0 0 . 9 1.8 2 . 7 - 2 . 7 - 1.8 - 0 . 9 0 0 . 9 1.8 2 . 7 - 9 - 9 ´ ´ T i m e [ s e c ] ( 1 0 ) ( 1 0 ) T i m e [ s e c ] SSA-UWB pulse wavelet realization using Soft-Spectrum Adaptation UWB test-bed with 4-bit quantization (128 and 256 samples per pulse) SSA-UWB pulse generation (Test-bed,128 samples, 4bit) SSA-UWB pulse generation (Test-bed,256 samples, 4bit) CRL & CRL-UWB Consortium
1 1 Q 4 S A M P L E 5 1 2 Q 4 S A M P L E 1 0 2 4 0 . 7 5 0 . 7 5 0 . 5 0 . 5 e e 0 . 2 5 0 . 2 5 d d u u t t i i l l 0 0 p p m m A A - 0 . 2 5 - 0 . 2 5 - 0 . 5 - 0 . 5 - 0 . 7 5 - 0 . 7 5 - 1 - 1 - 2 . 7 - 1.8 - 0 . 9 0 0 . 9 1.8 2 . 7 - 2 . 7 - 1.8 - 0 . 9 0 0 . 9 1.8 2 . 7 - 9 - 9 ´ ´ T i m e [ s e c ] T i m e [ s e c ] ( 1 0 ) ( 1 0 ) SSA-UWB pulse wavelet realization using Soft-Spectrum Adaptation UWB test-bed with 4-bit quantization (512 and 1024 samples per pulse) SSA-UWB pulse generation (Test-bed, 512 samples, 4bit) SSA-UWB pulse generation (Test-bed, 1024 samples, 4bit) CRL & CRL-UWB Consortium
SSA-UWB pulse wavelet realization using Soft-Spectrum Adaptation UWB test-bed with 4-bit quantization (128 samples per pulse) 128 samples Spectrum characteristics of SSA-UWB optimal pulse (Matlab simulation, 128 samples, no quantization) Spectrum characteristics of SSA-UWB optimal pulse (Test-bed, 128 samples, 4bit) CRL & CRL-UWB Consortium
256 samples SSA-UWB pulse wavelet realization using Soft-Spectrum Adaptation UWB test-bed with 4-bit quantization (256 samples per pulse) Spectrum characteristics of SSA-UWB optimal pulse (Matlab simulation, 256 samples, no quantization) Spectrum characteristics of SSA-UWB optimal pulse (Test-bed, 256 samples, 4bit) CRL & CRL-UWB Consortium
512 samples SSA-UWB pulse wavelet realization using Soft-Spectrum Adaptation UWB test-bed with 4-bit quantization (512 samples per pulse) Spectrum characteristics of SSA-UWB optimal pulse (Matlab simulation, 512 samples, no quantization) Spectrum characteristics of SSA-UWB optimal pulse (Test-bed, 512 samples, 4bit) CRL & CRL-UWB Consortium
1/8 sample 1024 samples SSA-UWB pulse wavelet realization using Soft-Spectrum Adaptation UWB test-bed with 4-bit quantization (1024 samples per pulse) Spectrum characteristics of SSA-UWB optimal pulse (Matlab simulation, 1024 samples, no quantization) Spectrum characteristics of SSA-UWB optimal pulse (Test-bed, 1024 samples, 4bit) CRL & CRL-UWB Consortium
64 samples 64 samples SSA-UWB pulse wavelet realization using Soft-Spectrum Adaptation UWB test-bed with 4-bit quantization (64 samples per pulse) SSA-UWB pulse generation (Test-bed, 64 samples, 4bit) Spectrum characteristics of SSA-UWB optimal pulse (Test-bed, 64 samples, 4bit) CRL & CRL-UWB Consortium
3. Effects of two kinds of Ultra Wideband antennas on implementation issues of SSA-UWB pulse wavelets (3.1) T-type antenna (3.2) K-type antenna (3.3) Pre-equalization for SSA-UWB pulse shape calibration CRL & CRL-UWB Consortium
Transfer function (S11) characteristics of T-type antenna 0 -5 -10 -15 Return Loss (dB) -20 -25 -30 -35 -40 -45 0 50 100 150 200 250 300 350 400 450 Frequency (samples) 2.32GHz 3.695GHz 5.070GHz 6.44GHz 7.82GHz 9.195GHz 10.57GHz 11.945GHz 3.1 T-type UWB antenna designed in CRL & CRL-UWB Consortium Measurement setup for T-type antenna characteristics in CRL (Frequency domain, transfer function, S11, S21, etc.) Measured transfer function of T-type antenna ( S11) CRL & CRL-UWB Consortium
0.06 0.04 0.02 0 -0.02 Impulse response of T-type antenna transfer function (S11) Phase feature of T-type antenna transfer function (S11) 0 -0.04 -5 -0.06 -10 -0.08 Relative phase (degree) Relative amplitude -15 -0.1 -20 -0.12 -25 -0.14 0 20 40 60 80 100 120 140 -30 0 50 100 150 200 250 300 350 400 450 Time (samples) Frequency (samples) T-type UWB antenna designed in CRL & CRL-UWB Consortium (Cont.) CRL & CRL-UWB Consortium
SSA-UWB optimized pulse wavelet generation Spectrum characteristics of optimalSSA-UWB pulse wavelet 2 0 -10 1.5 -20 1 -30 0.5 -40 Relative amplitude Relative amplitude (dB) -50 0 -60 -0.5 -70 -1 -80 (3.12GHz) (5.8GHz) -1.5 -90 0 20 40 60 80 100 120 140 0 50 100 150 200 250 300 0.0ns 0.56ns 1.125ns 1.6875ns 2.25ns 2.8125ns 3.375ns 0.0GHz 3.47GHz 6.94GHz 10.41GHz 13.88GHz 17.35GHz Time (128 samples=3.6 ns) Frequency (1 sample=69.4MHz) Effects of T-type Ultra Wideband antenna on SSA-UWB pulse shape CRL & CRL-UWB Consortium
Reflected SSA-UWB pulse waveform by T-type antenna Spectrum characteristics of reflected SSA-UWB pulse (T-type antenna) 2 -10 1.5 Reflected pulse -20 1 Generated pulse -30 0.5 -40 Relative amplitude Relative amplitude (dB) -50 0 -60 -0.5 -70 -1 -80 -1.5 -90 0 50 100 150 200 250 300 0 50 100 150 200 250 300 Frequency (samples) Time (samples) Effects of T-type Ultra Wideband antenna on SSA-UWB pulse shape (Cont.) CRL & CRL-UWB Consortium
Transfer function (S11) characteristics of K-type antenna Phase feature of K-type antenna transfer function (S11) 0 0 -20 -5 -40 -60 -10 Relative phase (degree) Return Loss (dB) -80 -15 -100 -120 -20 -140 -25 0 20 40 60 80 100 120 140 160 180 -160 0 20 40 60 80 100 120 140 160 180 3.0GHz 3.9GHz 4.9GHz 5.9GHz 6.9GHz 7.9GHz 8.9GHz 9.9GHz 10.9GHz Frequency (samples) Frequency (samples) 3.2 K-type UWB antenna designed in CRL & CRL-UWB Consortium CRL & CRL-UWB Consortium
Impulse response of K-type antenna transfer function (S11) 0.08 0.06 0.04 0.02 Relative amplitude 0 -0.02 -0.04 -0.06 -0.08 0 20 40 60 80 100 120 140 160 180 Time (samples) K-type UWB antenna designed in CRL & CRL-UWB Consortium (Cont.) CRL & CRL-UWB Consortium
Reflected SSA-UWB pulse waveform by K-type antenna Spectrum characteristics of reflected SSA-UWB pulse waveform (K-type antenna) -10 2 -20 Reflected pulse 1.5 -30 Generated pulse 1 -40 -50 0.5 Relative amplitude (dB) Relative amplitude -60 0 -70 -0.5 -80 -90 -1 -100 -1.5 -110 0 50 100 150 200 250 300 0 50 100 150 200 250 300 Time (samples) Frequency (samples) Effects of K-type Ultra Wideband antenna on SSA-UWB pulse shape CRL & CRL-UWB Consortium
Comparisons of effects of T- & K-type Ultra Wideband antennas on SSA-UWB pulse shape Spectrum characteristics of reflected SSA-UWB pulse waveforms by T- & K-type antenna -10 K-type antenna -20 -30 T-type antenna -40 -50 Relative amplitude (dB) -60 -70 -80 -90 -100 -110 0 50 100 150 200 250 300 Frequency (samples) CRL & CRL-UWB Consortium
Spectrum characteristics of reflected & required SSA-UWB pulse waveforms by T- & K-type antenna 0 -10 -20 K-type antenna -30 T-type antenna -40 Required spectrum Relative amplitude (dB) -50 -60 -70 -80 -90 0 50 100 150 200 250 300 Frequency (samples) Comparisons of effects of T- & K-type Ultra Wideband antennas on SSA-UWB pulse shape (Cont.) CRL & CRL-UWB Consortium
channel antenna filter filter antenna X Y C Fr Ar Ft At Pulse shape in both time and frequency domain is strongly affected by filter, antenna and channel characteristics. SSA pulse generator With Pre-equalization filter antenna X Xpre X At Ft Xpre=X Ft -1At-1 Xpost channel antenna filter Post-equalization Y C Fr Ar Xpost=YC-1 Ar-1 Fr-1 3.3 Pre-equalization for SSA-UWB pulse shape calibration CRL & CRL-UWB Consortium
Spectrum of Pre-equalized SSA-UWB pulse wavelet on the air (T-type antenna) Pre-equalized SSA-UWB pulse for T-type antenna Pre-equalized pulse 2 0 Required pulse -10 1.5 -20 1 -30 -40 0.5 Relative amplitude (dB) Relative amplitude -50 0 -60 -0.5 -70 -80 -1 -90 0 50 100 150 200 250 300 -1.5 0 50 100 150 Frequency (samples) Time (samples) Pre-equalization for SSA-UWB pulse wavelet corresponding to T-type antenna CRL & CRL-UWB Consortium
Spectrum of Pre-equalized SSA-UWB pulse wavelet on the air (K-type antenna) Pre-equalized SSA-UWB pulse (K-type antenna) 0 2 Pre-equalized pulse -10 1.5 -20 Required pulse -30 1 -40 Relative amplitude (dB) 0.5 Relative amplitude -50 -60 0 -70 -0.5 -80 -90 -1 0 50 100 150 200 250 300 Frequency (samples) -1.5 0 50 100 150 200 250 300 Time (samples) Pre-equalization for SSA-UWB pulse wavelet corresponding to K-type antenna CRL & CRL-UWB Consortium
Spectrum characteristics of SSA-UWB pulse wavelet on-the-air (No Pre-equalization) Spectrum of Pre-equalized & required SSA-UWB pulse wavelets on-the-air (T- & K-type antenna) 0 0 K-type antenna -10 -10 T-type antenna -20 -20 -30 -30 Required pulse -40 Relative amplitude (dB) -40 Relative amplitude (dB) -50 -50 -60 -60 -70 -70 -80 -80 -90 0 50 100 150 200 250 300 -90 0 50 100 150 200 250 300 Frequency (samples) Pre-equalization for SSA-UWB pulse wavelet realizing spectrum matching Frequency (samples) CRL & CRL-UWB Consortium
4. Conclusion remarks • We has tested the effects of quantization bits and sampling scheme on the implementation issues of SSA-UWB pulse wavelets. Test-bed results are encouraging • We also have investigated the effects of two specific Ultra Wideband antennas on the implementation issues of SSA-UWB pulse wavelets CRL’s T-type antenna CRL’s K-type antenna Measurement and simulation results are encouraging as well • Scalable and adaptive performance improvement can be further expected by utilizing various improved UWB devices. CRL & CRL-UWB Consortium
5. Backup materials CRL & CRL-UWB Consortium
SSA-UWB optimized pulse wavelet generation Spectrum characteristics of SSA-UWB optimal pulse wavelet -0 1.5 -10 1 -20 -30 0.5 Relative amplitude (dB) Relative amplitude -40 -50 0 -60 -70 -0.5 -80 -90 -1 0 20 40 60 80 100 120 140 0 50 100 150 200 250 300 Time (samples) Frequency (samples) SSA-UWB pulse wavelet with adaptive spectral notches achieving coexistence, flexibility and efficient power transmission CRL & CRL-UWB Consortium
Spectrum characteristics of reflected SSA-UWB pulse waveform (T-type antenna) -20 -30 -40 -50 -60 Relative amplitude (dB) -70 -80 -90 -100 -110 0 50 100 150 200 250 300 Frequency (samples) CRL & CRL-UWB Consortium
Reflected SSA-UWB pulse by T-type antenna 1.5 1 0.5 Relative amplitude 0 -0.5 -1 -1.5 0 20 40 60 80 100 120 140 Time (samples) CRL & CRL-UWB Consortium
Spectrum characteristics of reflected SSA-UWB pulse waveform (K-type antenna) -20 -30 -40 -50 -60 Relative amplitude (dB) -70 -80 -90 -100 -110 0 50 100 150 200 250 300 Frequency (samples) CRL & CRL-UWB Consortium
Reflected SSA-UWB pulse waveform by K-type antenna 1.5 1 0.5 0 Relative amplitude -0.5 -1 -1.5 0 50 100 150 200 250 300 Time (samples) CRL & CRL-UWB Consortium
Spectrum characteristics of reflected SSA-UWB pulse waveform -20 -30 K-type antenna -40 T-type antenna -50 -60 Relative amplitude (dB) -70 -80 -90 -100 -110 0 50 100 150 200 250 300 Frequency (samples) CRL & CRL-UWB Consortium
Spectrum characteristics of reflected & required SSA-UWB pulse waveforms -10 K-type antenna -20 T-type antenna -30 -40 Relative amplitude (dB) -50 -60 -70 -80 -90 0 50 100 150 200 250 300 Frequency (samples) CRL & CRL-UWB Consortium
SSA-UWB optimized pulse wavelet generation Spectrum characteristics of SSA-UWB optimal pulse wavelet 1.5 0 -20 1 -40 -60 0.5 -80 Relative amplitude (dB) Relative amplitude -100 -120 0 -140 -160 -0.5 -180 -200 -1 0 50 100 150 200 250 300 0 20 40 60 80 100 120 140 Time (samples) Frequency (samples) SSA-UWB pulse wavelet with adaptive spectral notches achieving coexistence, flexibility and efficient power transmission (Cont.) CRL & CRL-UWB Consortium
Spectrum characteristics of reflected SSA-UWB pulse waveform (T-type antenna) -20 -40 -60 Relative amplitude (dB) -80 -100 -120 -140 0 50 100 150 200 250 300 Frequency (samples) CRL & CRL-UWB Consortium
Reflected SSA-UWB pulse waveform by T-type antenna 1.5 1 0.5 Relative amplitude 0 -0.5 -1 -1.5 0 20 40 60 80 100 120 140 Time (samples) CRL & CRL-UWB Consortium
Spectrum characteristics of reflected SSA-UWB pulse waveform (K-type antenna) 0 -50 -100 Relative amplitude (dB) -150 -200 -250 0 50 100 150 200 250 300 Frequency (samples) CRL & CRL-UWB Consortium
Reflected SSA-UWB pulse waveform by K-type antenna 1.5 1 0.5 Relative amplitude 0 -0.5 -1 -1.5 0 50 100 150 200 250 300 Time (samples) CRL & CRL-UWB Consortium