A Comparison of Opportunistic Transmission Schemes with Reduced Channel Information Feedback in OFDMA Downlink

In this paper, we consider downlink throughput performances of multiuser orthogonal frequency division multiplexing (multiuser OFDM) with reduced channel information feedback schemes. Specifically, two types of reduced feedback schemes, namely, 1-bit per sub-carrier and selective feedback scheme are considered and compared with each other in terms of average network throughput. For the latter, since the exact analysis is complicated, we resort to an approximate analysis. Simulations results will also be provided to verify the approximate analysis. Since the strict throughput comparison for given number of feedback bits per user is quite difficult, rather we compare their general behaviors in various system configurations with different system parameters, which can give us an insight into practical system design with those reduced feedback schemes.