The inner and outer bounds on the capacity of the 3‐user GBC‐SKT with unequal state variances
Abstract The “Gaussian BroadCast channel (GBC) with States non‐causally Known at the Transmitter” (GBC‐SKT) introduces Gaussian broadcast channel with additive i.i.d. Gaussian states non‐causally known at the transmitter. In this model additive interferences on links are considered as states which a...
| Main Author: | |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Wiley
2021-08-01
|
| Series: | IET Communications |
| Online Access: | https://doi.org/10.1049/cmu2.12187 |
| Summary: | Abstract The “Gaussian BroadCast channel (GBC) with States non‐causally Known at the Transmitter” (GBC‐SKT) introduces Gaussian broadcast channel with additive i.i.d. Gaussian states non‐causally known at the transmitter. In this model additive interferences on links are considered as states which are only non‐causally known to the transmitter. Such cases are encountered in, e.g., wireless multiple‐antenna multicasting scenario. Previously the approximate capacity of the K‐user GBC‐SKT has been studied where all states but one are assumed to have the same variance. In this work, the capacity of the 3‐user GBC‐SKT channel communicating only common messages is studied. All three states are assumed to have different variances. The key point is how to simultaneously pre‐code the common message against three states. Two transmission strategies are proposed by combination of power‐sharing and time‐sharing methods and two inner bounds are derived. From analytical and simulation results it is seen that one inner bound outperforms the other inner bound. Moreover, the outer bound on the capacity of this channel is driven and the conditions on the state variances for which, the capacity of the 3‐user GBC‐SKT channel is derived to within 1 bpcu, are extracted. |
|---|---|
| ISSN: | 1751-8628 1751-8636 |