Digital techniques for mobile radio chirp sounders

Author

Salous, S. ; Nikandrou, N. ; Bajj, N.F.

Author_Institution

Dept. of Electr. Eng. & Electron., Univ. of Manchester Inst. of Sci. & Technol., UK

Volume

145

Issue

3

fYear

1998

fDate

6/1/1998 12:00:00 AM

Firstpage

191

Lastpage

196

Abstract

The theory of chirp sounding is reviewed. This is followed by a description of a digital mobile radio chirp sounder which is implemented using direct digital frequency synthesisers (DDFS), field programmable gate arrays and microcontrollers. The gate arrays and the microcontroller provide the user interface via either a keypad or a PC, generate the programming words for the DDFS and two phase-locked-loop (PLL) synthesisers, synchronise the transmitter´s sweep to the receiver´s sweep and implement a beat-frequency-oscillator DDFS. The results demonstrate that the digital chirp sounder provides full programmability of the various chirp waveform parameters, bandwidths of up to 90 MHz which are suitable for both indoor and outdoor environments, offline processing to obtain different channel characteristics, and moderate averaging to obtain a dynamic range better than 35 dB

Keywords

chirp modulation; digital radio; direct digital synthesis; field programmable gate arrays; frequency modulation; indoor radio; land mobile radio; microcontrollers; phase locked loops; 90 MHz; FMCW; PLL synthesisers; averaging; bandwidths; beat-frequency-oscillator DDFS; channel characteristics; chirp waveform parameters; digital techniques; direct digital frequency synthesisers; dynamic range; field programmable gate arrays; indoor environment; keypad; microcontrollers; mobile radio chirp sounders; offline processing; outdoor environment; phase-locked-loop; receiver sweep; synchronisation; transmitter sweep; user interface;

fLanguage

English

Journal_Title

Communications, IEE Proceedings-

Publisher

iet

ISSN

1350-2425

Type

jour

DOI

10.1049/ip-com:19982078

Filename

689416