Minimum BER Analysis in Interference Channels

In spectrum sharing channels, a secondary user can simultaneously transmit data with a primary user as long as the so called interference temperature limit is kept less than a certain permissible level. In this paper, we consider a spectrum sharing scenario over a Nakagami-m fading channel, and formulate a minimization problem for the average bit error rate (BER) that can be achieved by a secondary user while keeping the interference level introduced to the primary user below a given threshold. We derive new results for the minimum average BER under either average or peak interference power constraints at the primary receiver. This paper also investigates the significance of having extra side information on the status of different channels at the secondary transmitter. Finally, the impact of posing additional constraints on the transmit power at the secondary transmitter is discussed via numerical results.