Implementation

Interactive Explorer 2

Explore key concepts interactively

Parameters

Quick Check

Key concept question for section 2?

Option A

Option B

Option C

Common Mistake: Common Mistake in Section 2

Mistake:

Overlooking a critical implementation detail.

Correction:

Always verify results against known benchmarks and theoretical predictions.

Key Term 2

Core concept from section 2 of chapter 49.

Definition:

Simulation Validation

Validate against known results:

  1. BPSK AWGN: Pb=Q(2Eb/N0)P_b = Q(\sqrt{2E_b/N_0})
  2. Rayleigh: Pbβ‰ˆ1/(4Eb/N0)P_b \approx 1/(4E_b/N_0)
  3. LDPC waterfall curve shape

Theorem: Shannon Capacity

MIMO channel capacity: C=log⁑2det⁑(I+SNRNtHHH)C = \log_2\det\left(\mathbf{I} + \frac{\text{SNR}}{N_t}\mathbf{H}\mathbf{H}^H\right) Your simulator should approach this bound with proper coding.

Theorem: Theoretical BER Bounds

For MM-QAM in AWGN: Pbβ‰ˆ4(Mβˆ’1)Mlog⁑2MQ(3log⁑2MMβˆ’1SNR)P_b \approx \frac{4(\sqrt{M}-1)}{\sqrt{M}\log_2 M} Q\left(\sqrt{\frac{3\log_2 M}{M-1}\text{SNR}}\right)

Theorem: LDPC Threshold

LDPC codes have a decoding threshold: below a certain SNR, the BER drops sharply (waterfall effect). The threshold approaches Shannon capacity for well-designed codes.