Ali Al- Saihati ID# 200350130

1. King Fahd University of Petroleum & Minerals Electrical Engineering DepartmentEE 578 Simulation of Wireless SystemsRadio Communication Channels Assignment # 2 Ali Al-Saihati ID# 200350130

2. OUTLINE • AWGN Channel. • Rayleigh Fading Channel. • Programs.

3. AWGN Channel • Received signal: • Noise power spectral density:

5. Rayleigh Fading Channel. • The transmitted signal from a base station radiates in all directions. • Some of the transmitted waves are reflected, diffracted or scattered. • Reflection occurs when a wave impinges upon a smooth surface of large size relative to λ (wavelength). • Diffraction occurs when the path is blocked by an object with large dimensions relative to λ and sharp irregularities (edges). • Scattering occurs when a wave impinges upon an object with dimensions on the order of λ or less. • The phase of the received signals varies. Depending on the value of the phase, they might add constructively or destructively.

8. If N is large: • r(t) can be expressed in terms of amplitude and phase • Where R(t) and Ѳ(t) are:

9. Doppler Shift • Any motion in the plane in which the electromagnetic wave is traveling towards or away from the receiver results in a shift in the carrier frequency. • If the transmitter and receiver are approaching, the frequency is higher while if they are moving apart, the frequency is lower. • The Doppler shift is given by: fd= v cosѲ /λ

10. Programs • 1) mvalue: Calculates the mean of a given data. • 2) disper: Calculates the variance and standard deviation of a given data. • 3) main: Calculates mean, variance and standard deviation for a given data. • 4) comb: Generates additive white Gaussian noise. • 5) fade: Generate Rayleigh fading. • 6) sefade: Generates frequency selecting fading. • 7) delay: Gives delay to input signal. • 8) bpskev: Evaluation program of fading counter based BPSK transmission scheme

11. Evaluation program of fading counter • The fading counter is updated after each simulation loop. • The simulation time could be reduced by adjusting the update time. • When the update time is equal to the observation time, the transmission performance could be evaluated under continuous changed signal level. • It takes a long time to stabilize the simulated performance. • When the update time is larger than the observation time, the transmission performance could be evaluated under Rayleigh fading with a small number of simulation loops. • The simulation result may not be precise.

13. Thank You