Title :
Performance of π/4-QDPSK in a Rayleigh/lognormal/delay spread/AWGN-cochannel interference environment
Author :
Le, Minh T. ; Sheikh, Asrar U.
Author_Institution :
Dept. of Syst. & Comput. Eng., Carleton Univ., Ottawa, Ont., Canada
Abstract :
The performance of π/4-QDPSK system is presented in a fast Rayleigh fading/slow lognormal shadowing/delay spread/AWGN channel in the presence of cochannel interference. The performance of the system is measured in terms of symbol error rate (SER). The system was simulated using two-ray model for normalized value of Doppler shift (0.001), degree of shadowing (σ=6), and several values of time delays and carrier-to-interference ratios. It is seen that the system performance is limited by the presence of cochannel interference. When cochannel interference is negligible, the system performance is dominated by the ratio between the main path signal and the delayed path signal, and the differential time delay between them. It is observed that the shadowing degrades the system performance at low CNR but not at high CNR (i.e., CNR>50 dB). The irreducible symbol error rate (ISER) does not vary significantly as the differential time delay between the two path varies
Keywords :
cellular radio; delays; digital radio systems; fading; phase shift keying; radiofrequency interference; telecommunication channels; white noise; π/4-QDPSK; AWGN channel; CNR; Doppler shift; Rayleigh fading; carrier-to-interference ratios; cochannel interference; degree of shadowing; delay spread; digital cellular system; irreducible symbol error rate; performance; slow lognormal shadowing; symbol error rate; time delays; two-ray model; AWGN; Additive noise; Additive white noise; Degradation; Delay effects; Error analysis; Interchannel interference; Radiofrequency interference; Rayleigh channels; Shadow mapping;
Conference_Titel :
Vehicular Technology Conference, 1992, IEEE 42nd
Conference_Location :
Denver, CO
Print_ISBN :
0-7803-0673-2
DOI :
10.1109/VETEC.1992.245452
