Ber Performance

---
name: ber-performance
description: Evaluates the bit error rate (BER) performance of a Reconfigurable Intelligent Surface (RIS) aided spatial media-based modulation system compared to baseline schemes (SM, MBM, QSM) under uncorrelated Rayleigh fading channels. Use when the user has predictions and gold and needs to compute Bit Error Rate (BER).
metadata:
  skill_kind: metric
  source_arxiv: 2211.07720
  bibtex_key: ozden2022ris
  confidence: high
---

# ber-performance

> Reconfigurable Intelligent Surface Aided Spatial Media-Based Modulation — Ozden et al. (2022) (arXiv:2211.07720, 2022)

## What this evaluates

Evaluates the bit error rate (BER) performance of a Reconfigurable Intelligent Surface (RIS) aided spatial media-based modulation system compared to baseline schemes (SM, MBM, QSM) under uncorrelated Rayleigh fading channels.

## Datasets

- (no dataset; pure metric skill)

## Metrics

- `Bit Error Rate (BER)` **(primary)** — range: [0, 1]
  - The fraction of incorrectly detected bits out of the total transmitted bits. Computed as $P_b = N_{error} / N_{total}$ over a simulated Rayleigh fading channel.

## Input / output format

**Input**: System configuration parameters (modulation order M, transmit antennas n_T, RIS elements N, active RF mirrors m_rf) and SNR values. Simulated with a single receive antenna over uncorrelated Rayleigh fading channels.

**Output**: BER curves or tables plotting error rate against SNR for varying system parameters and modulation schemes.

## Scoring recipe

```python
Simulate transmission over Rayleigh fading channel for each SNR point.
Count total transmitted bits and incorrectly detected bits.
Compute BER = (incorrectly detected bits) / (total transmitted bits).
Plot BER vs SNR for each modulation scheme.
```

## Common pitfalls

- BER is evaluated via Monte Carlo simulation rather than hardware testing.
- Comparisons maintain constant spectral efficiency, requiring different parameter configurations for each baseline scheme.
- Increasing active RF mirrors improves spectral efficiency but degrades BER performance.

## Evidence (verbatim from paper)

> The optimal ML and ELC detector for the RIS-SMBM system are used for the estimation of the transmitted symbol and active indices at the receiver. All simulation results are obtained under the assumption that fading channels are uncorrelated Rayleigh distributions. Also, for all systems, the receiver antenna is selected as one. ... We present BER performance comparisons of RIS-SM, RIS-MBM, RIS-QSM, and RIS-SMBM systems for η=8 bits/s/Hz and N=128 in Fig. 4.

## Citation

```bibtex
@misc{ozden2022ris,
  title={Reconfigurable Intelligent Surface Aided Spatial Media-Based Modulation},
  author={Ozden et al. (2022)},
  year={2022},
  note={arXiv:2211.07720}
}
```

- arXiv: 2211.07720