Spectral shaping of UWB signals for time-hopping impulse radio
Publikation/Tidskrift/Serie: IEEE Journal on Selected Areas in Communications
Dokumenttyp: Artikel i tidskrift
Förlag: IEEE--Institute of Electrical and Electronics Engineers Inc.
This paper studies the design of signaling waveforms for time-hopping impulse radio (TH-IR) with limits on the power spectral density. Such restrictions are imposed by the spectral mask prescribed by frequency regulators for ultra-wideband (UWB) signals. The "conventional" TH-IR system with pulse-position modulation and time-hopping multiple access gives rise to spectral lines that either violate the regulations, or require a significant power backoff. To remedy this situation, we propose the use of polarity randomization, which eliminates the spectral lines and also leads to a smoothing of the continuous part of the spectrum. We analyze different variants of the polarity randomization, considering short and long randomization sequences, as well as symbol-based or pulse-based randomization. We analyze the effect of this technique on both pulse position modulation and binary phase-shift keying modulation.
- Electrical Engineering, Electronic Engineering, Information Engineering
- spectral lines
- polarity randomization
- power spectral density
- time-hopping impulse radio (TH-IR)
- ISSN: 1558-0008