Abstract
Performance analysis of the minimum-mean-square-error (MMSE) linear multiuser detector is considered in an environment of nonorthogonal signaling and additive white Gaussian noise. In particular, the behavior of the multiple-access interference (MAI) at the output of the MMSE detector is examined under various asymptotic conditions, including: large signal-to-noise ratio; large near-far ratios; and large numbers of users. These results suggest that the MAI-plus-noise contending with the demodulation of a desired user is approximately Gaussian in many cases of interest. For the particular case of two users, it is shown that the maximum divergence between the output MAI-plus-noise and a Gaussian distribution having the same mean and variance is quite small in most cases of interest. It is further proved in this two-user case that the probability of error of the MMSE detector is better than that of the decorrelating linear detector for all values of normalized crosscorrelations not greater than 1/2 + √2 +√3 ≅ 0.9659.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 858-871 |
| Number of pages | 14 |
| Journal | IEEE Transactions on Information Theory |
| Volume | 43 |
| Issue number | 3 |
| DOIs | |
| State | Published - 1997 |
All Science Journal Classification (ASJC) codes
- Information Systems
- Computer Science Applications
- Library and Information Sciences
Keywords
- Asymptotic normality
- Decorrelating detector. MMSE detection
- Divergence
- Multiuser detection
- Probability of error