Generalized Distributed Information Bottleneck for Fronthaul Rate Reduction at the Cloud-RANs Uplink

The focus is on Wyner-Ziv type distributed fronthaul compression for the uplink of Cloud Radio Access Networks with single-hop topology to leverage the correlation among the received signals of neighboring Radio Access Points. For this, we highlight the relation between the problem at hand and the Chief Executive Officer source coding under logarithmic-loss distortion and depict that the achievability arguments from the latter verify addressing the postulated optimization. Subsequently, we derive the pertinent optimal solution and utilize that as the backbone of the Generalized Distributed Information Bottleneck (G-DIB) routine proposed here to tackle the considered remote source coding problem. As its name suggests, this novel approach in its very core spirit extends the State-of-the-Art Distributed Information Bottleneck (DIB) method by enabling individual rate constraints for various fronthaul links.