Scenario description: Assume you got a new wireless sensor device with circuit power consumption of P_elec = 0.015mW. Frequency bandwidth (i.e. symbol rate) is 1MHz. You have a packet with 125 bytes to send. Assume there is no other overhead, and you can ideally turn on and off the transmission without additional power cost. Now you can choose using various data rates to transmit this packet, while maintaining the same BER at 0.0001 with the following assumption: using BPSK, the required TX amplifier power consumption of P_t =0.02mW; using QPSK, the required TX amplifier power consumption of P_t =0.05mW. Receiver energy consumption is not a concern. Questions: Please calculate the energy consumption (in unit of nJ â Nano-Joule) of transmitting this packet, using BPSK and QPSK schemes, respectively. Do you prefer slow BPSK transmission to save power, or to transmit quickly with QPSK and then sleep (3 point)?
