| This thesis studies various relaying strategies for two types of Gaussian Z-relay interference channels. The main results of this thesis are as follows: For the Gaussian Z-interference channel with a digital link from the clean receiver to the interfered receiver, it is shown that digital relaying is capacity achieving in the strong interference regime, and asymptotically efficient in the weak interference regime in the sense that each relay bit improves the sum capacity by one bit in the high signal-to-noise ratio and high interference-to-noise ratio limit. For the Gaussian Z-interference channel with a digital link from the interfered receiver to the clean receiver, it is shown that, in the strong interference regime, decode-and-forward strategy is capacity achieving. In the weak interference regime, an achievable rate region is derived using a quantize-and-forward strategy. However, in this regime, the sum-rate gain due to the digital link is upper bounded by half bit. |
