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Alamouti Scheme Simulator


Alamouti Scheme Virtual Lab

Alamouti Scheme BPSK (Baseband) Simulation

  • Phase 1: Enter input bits and SNR, then click Generate Message.
  • Phase 2: Generate NRZ Signal to see BPSK mapping.
  • Phase 3: Visualize the Transmitted Signal from both antennas.
  • Phase 4: Observe the Rayleigh Fading coefficients and the final Demodulated output.

* Ensure an even number of bits for Alamouti Pairs.

System Controls

Channel Matrix (H)

h11: +j
h21: +j

BER Results

SNR (dB)BER

Workflow & Mathematical Model

1. Encoding (Space-Time Block Coding)

Alamouti's STBC maps two symbols [s1, s2] over two time slots:

Time 1: [s1, s2]
Time 2: [-s2*, s1*]

* Note: In BPSK, the conjugate s* equals s.

2. The Received Signal

The received signal at the single receiver antenna is modeled as:

y1 = h1s1 + h2s2 + n1
y2 = -h1s2* + h2s1* + n2

Where hn is Rayleigh fading and nn is AWGN noise.

3. Maximum Likelihood Combining

The receiver uses Channel State Information (CSI) to combine the signals:

ŝ1 = h1*y1 + h2y2*
ŝ2 = h2*y1 - h1y2*
📊 MATLAB & ONLINE SIMULATIONS (Web-Based)
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