Spectral efficiency considerations in ultrawideband (UWB) radar and communications

Chinmay Rao, Ram Mohan Narayanan

Research output: Contribution to journalConference articlepeer-review


Recent years have seen a rapid expansion of ultrawideband (UWB) technology in radar and communications applications. While the initial impetus for UWB systems was derived from the need for high-resolution radar applications for the military, these systems are now used in a variety of consumer applications such as cellular phones and satellite television. The principal motivation for using UWB is that it offers improved spectral efficiency, i.e., it permits multiple users to occupy and operate within the same frequency band with minimal cross-interference. Currently, UWB schemes use some form of pulse train modulation to encode data onto the carrier. However, these schemes are not always ideal since: (a) these are not the most spectrally efficient due to the fact that additional users can be added by using alternate schemes, (b) these do not possess anti-jam capability since it is possible to estimate the carrier frequency the signal, and (c) such type of modulation possess frequency sidelobes that might interfere with UWB devices in adjacent bands. Our research aims to characterize the above shortcomings and to ultimately develop a method for defining and estimating an appropriate spectral efficiency metric. We also present results of our study of new waveform designs, for both radar and communications, resulting in optimal sharing of frequency segments with minimum impact to system functionality and avoidance of spectral fratricide. One such waveform investigated and described herein is a combination of pulse shape and pulse position modulation, primarily for optimizing the performance of UWB communications systems that use pulse trains.

Original languageEnglish (US)
Article number31
Pages (from-to)224-234
Number of pages11
JournalProceedings of SPIE - The International Society for Optical Engineering
StatePublished - 2005
EventDefense Transformation and Network-Centric Systems - Orlando, FL, United States
Duration: Mar 29 2005Mar 31 2005

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering


Dive into the research topics of 'Spectral efficiency considerations in ultrawideband (UWB) radar and communications'. Together they form a unique fingerprint.

Cite this