描述.txt

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ALAMOUTI performs Monte-Carlo simulation and estimates Bit Error Rate (BER) of Alamouti Scheme [1] over Rayleigh channel. The scheme presumes 2 transmit (Tx) and arbitrary number of receive (Rx) elements. If Rx=1 (one receive element) the ALAMOUTI is transformed to the order 2 transmit diversity scheme with Maximum Ratio Combining (MRC). The modulation format is MPSK with arbitrary order M which can be controlled by user.

The simulation parameters are entered using the built graphic user interface (GUI) and contains:

1. Number of pair symbols from both Tx elements to be transmitted: N. This number should be at least 10 times more that the expected 1/BER to provide low estimation error.

2. MPSK order M, must be a power of 2.

3. Signal-to-Noise-Ratio (SNR) in dB as a ratio of the average received power at one Rx element over the noise power at this element.

4. Number of transmit elements Tx=2 which cannot be changed by user.

5. Number of receive elements Rx, can be arbitrary.

The program does not check the format of the feeding parameters and does not produce any alert about incorrect values!

Pushbutton 'Start' starts the simulation with desired parameters and plots the estimated BER vs. SNR. 

Pressing 'Help' in the Help menu will pop up a notepad with the help information above.

To allow efficient vector programming ALAMOUTI is an equivalent Alamouti Scheme [1] i.e. a simulation where the time epochs are hidden.

Reference:
[1] S. M. Alamouti, A Simple Transmit Diversity Technique for Wireless Communications, IEEE Journal on Select Areas in Communications, vol. 16, no. 8, Oct. 1998.

Acknowledgement:
To Dr. Sander Stepanov from Israel Institute of Technology (Technion) for helpful discussion and useful comments on Alamouti algorithm.

Author: G. Levin, July 2004.