Optimizing throughput for limited receiver circuit power.

Maximizing the battery life time of mobile devices and sensor nodes increasingly becomes a challenge, and receiver power consumption tends to become more problematic than delivering adequate transmit power. We address the challenge of achieving the highest possible throughput per Watt of receiver circuit power. Our results show that optimum and adaptive tuning of the front-end parameters of the receiver can result in substantial power savings, compared to the common practice of a design for worst case conditions. We obtain a closed form solution for maximum throughput and the corresponding optimal overall system specifications. We confirm that handling the interference from nearby channels has a large influence, and our analysis concludes that adaptive control of the IP3 performance has an overarching impact. We further describe how the adaptive overall system settings can be translated into optimum gain and IP3 specifications of each of the individual stages that form the receiver cascade, considering both the accumulation of circuit noise and distortion products. The example of a WLAN system is elaborated to illustrate our method.