Title :
A simple modulation scheme for error performance improvement of low-deviation digital FM
Author :
Horikoshi, Jun ; Kimura, Yasuyuki
Author_Institution :
Dept. of Electron. Eng., Gunma Univ., Japan
fDate :
8/1/1995 12:00:00 AM
Abstract :
The paper proposes a simple digital modulation scheme named LF (lowpass filtered)-π/2 TFSK. Since it is essentially a constant envelope modulation scheme, it can be applied to severely band-limited channels such as land mobile and satellite mobile radio channels. Its error performance is superior to that of MSK modulation in band-limited channels at the cost of a slightly wider bandwidth (approximately 1.06 times) than GMSK. The required Eb/N0 with 2-bit differential detection at the error rate of 10-5 is 2.3 dB smaller than that of GMSK in an additive Gaussian channel and 3 dB smaller at the average error rate of 10-4 in a fast Rayleigh fading channel. The above result, obtained by an exact error rate analysis, was confirmed by laboratory experiments at a frequency of 880 MHz. The spectral characteristics were analyzed through computer simulations and the results were found to agree with those obtained from a hardware implementation
Keywords :
Gaussian channels; Rayleigh channels; digital filters; digital radio; error statistics; fading; frequency shift keying; land mobile radio; low-pass filters; mobile satellite communication; spectral analysis; 2-bit differential detection; 880 MHz; Eb/N0; additive Gaussian channel; average error rate; band-limited channels; constant envelope modulation scheme; digital modulation scheme; error performance; error rate; error rate analysis; fast Rayleigh fading channel; land mobile radio channel; low-deviation digital FM; lowpass filtered-π/2 TFSK; satellite mobile radio channel; spectral characteristics; Bandwidth; Costs; Digital filters; Digital modulation; Error analysis; Fading; Gaussian channels; Laboratories; Land mobile radio; Satellite broadcasting;
Journal_Title :
Vehicular Technology, IEEE Transactions on
