Joint communication and target detection with multiple antennas

We study a basic joint communication and sensing setting comprising a base station, an active user and a potential passive target. The base station wishes to send a message to the user and at the same time detect the presence or absence of the target. Both base station and user are equipped with multiple antennas. We characterize the fundamental performance trade-off between the communication and sensing tasks, captured in terms of the rate of reliable communication against the detection error exponent. In doing so, we identify optimal schemes for this multi-antenna joint communication and sensing setting.