Power efficiency in communication systems from a circuit perspective

We consider the minimization of the overall power consumption when communicating over a noisy single-input single-output channel while satisfying a certain throughput and error rate constraint. The total power dissipation includes the radiated power as well as the circuit power consumption. In the context of battery operated short range communication, where low power, low cost and small size are key requirements (e.g. standard IEEE 802.15.4), this circuit aware system optimization is crucial given the growing importance of “Green Communication”. In fact, the power dissipation of certain analog and digital components along the signal path reaches values in the order of or is even higher than the transmit power in such applications. Using an appropriate information-theoretic framework we derive the optimal bit-resolution of the analog-to-digital converter (ADC), the optimal choice of the noise figure for the low noise amplifier (LNA), the optimal operating input back-off (IBO) of the power amplifier (PA), as well as the optimum decoding (DEC) strategy as a function of the path-loss (i.e. the communication distance), that guarantee a certain net data rate R under a certain error probability P_e. This work is an extension to the work [1], where only the power of the analog components was considered.