UltraWideBand a.k.a. UWB

1
UltraWideBand a.k.a. UWB

• Chihou Lee ECE1352 December 2003

2
Introduction

• April 2002
• U.S. Federal Communications Commission (FCC)
  grants new spectrum for commercial use (3.1 GHz
  to 10.6 GHz)

Aiello,2003
3
UWB Modulation
Use IF signal to modulate RF carrier
Vary delay between pulses to encode signal PPM
(pulse position modulation)
4
Transceiver Architecture
Aiello, 2003
5
Implementation Challenges

• LNA Mixer are the most challenging components
  to build.
• Designing LNA
• narrowband LNA design no longer applies (cant
  use inductive emitter degeneration)
• Must match input/output over large frequency
  range
• Very few UWB LNA implementations (1) Sangyoub,
  2002
• Designing Mixer
• Mixer uses similar matching concepts as LNA to
  achieve wideband matching Sangyoub, 2002

6
LNA Design

• Presenting Sangyoub, 2003 UWB LNA design

Series-Shunt feedback Amplifier PROs good NF,
and wideband (use shunt-series to match input
output) CONs non-optimal biasing means low gain,
potential stability issues.
7
LNA Design (cont)

• Three new components L1, L2, Cf
• L1 Gain? as freq? b/c ZL1 wL1
• L2 Gain? as freq? b/c ZL2 wL2
• Cf decouples output from input allows for
  optimal biasing.

Careful consideration given to choosing component
values to avoid unstable system see Sangyoub,
2002
8
Summary

• UltraWideBand Technology
• Use Monopulses to carry data
• Easy circuit implementation (lower cost, power)
• Cant transmit long distance b/c low transmit
  power

9
References

• Aiello, 2003 G.Roberto Aiello, "Challenges for
  Ultra-wideband (UWB) CMOS Integration". RFIC
  2003.
• Cravotta, 2002 Nicholas Cravotta,
  "Ultrawidband the next wireless panacea?".
  www.edn.com, Oct, 2002.
• Sangyoub, 2002 Sangyoub Lee, "Design and
  Analysis of Ultra-Wide Bandwidth Impulse Radio
  Receiver", University of Southern California PhD
  Dissertation, 2002.
• Leeper, 2003 David G. Leeper Ultrawideband
  the next step in short range wireless, RFIC 2003
• Molisch, 2003 Andreas F. Molisch, Jinyun Zhang,
  Time hopping and frequency hopping in
  ultrawideband systems, IEEE 2003.
• Mitchell, 2001 Terry Mitchell, Broad is the
  way, IEE Review Jan 2001.
• Namgoong, 2003 Won Namgoong, A Channelized
  Digital Ultrawideband Receiver, IEEE
  Transactions on Wireless communications, 2003.
• Siwiak, 2001 Kazimierz Siwiak, UWB
  Introducing a New Technology, VTC 2001.
• Barras David Barras, A Comparison between UWB
  and Narrowband Transceivers.
• Lerdworatawee, 2003 Jongrit Lerdworatawee, Won
  Namgoong, Low Noise Amplifier Design for UWB,
  IEEE 2003.