Performance of Low Earth Orbit Satellite Systems with Coding

The effect of block, convolutional and Turbo coding on the probability of error and the capacity are investigated for CDMA Low Earth Orbit (LEO) Satellite systems. The model employed assumes a contaminated Gaussian traffic model to be more compatible with different population areas. The conventional Gaussian distribution can be considered as a special case.     

Performance of MRC Diversity Systems for the Detection of Signals with Nakagami Fading

Bit error rate (BER) is analyzed theoretically for diversity reception in Nakagami fading environment using anM-branch maximal ratio combiner (MRC). Coherent and incoherent reception of frequency shift keying (FSK) are considered, using the multiple branch diversity system for both identical and different diversity branch fading parameters. The effect of correlation is also considered for the dual diversity case. The results are extended to include coherent phase shift keying (CPSK) and differential phase shift keying (DPSK).     

Composite Macroscopic and Microscopic Diversity of Sectorized Macrocellular and Microcellular Mobile Radio Systems Employing RAKE Receiver over Nakagami Fading Plus Lognormal Shadowing Channel

This paper presents a generalized model of binary phase shift keying (BPSK) direct sequence code division multiple access (DS/CDMA) macrocellular and microcellular sectorized mobile radio systems over Nakagami fading plus lognormal shadowing channels. RAKE receiver, perfect and imperfect sectorization, voice activity monitoring, microscopic and composite microscopic plus macroscopic diversity are considered. The interrelationships among the number of interfering cells, sectorization degree, sectorization imperfection, voice activity factor, fading parameter, microscopic diversity degree, microscopic plus macroscopic diversity degree and the number of users are considered. Numerical results show that voice activity monitoring and sectorization can reduce multiple access interference (MAI). Furthermore, composite microscopic plus macroscopic diversity system can counteract the fast and slow fading components simultaneously.     

Generalized performance evaluation of low Earth orbit satellitesystems

A novel three-dimensional distribution traffic is proposed for low Earth orbit (LEO) satellite systems. The effect of the traffic geographical nonuniformity on the performance of these satellite systems is discussed