Wireless Powered Communications

This chapter focuses on wireless powered communications using far‐field radio frequency (RF) signals. It discusses three different types of wireless powered communications: simultaneous wireless information and power transfer; hybrid access point; and power beacon. The chapter reviews several important research issues on wireless powered communications. These research issues include effect of interference on wireless power, effect of interference by wireless power, exploitation of interference, and multiple antennas. For wireless powered communications, interference is some ambient RF energy that can actually be harvested for power. In most cases, the amount of harvested energy and the information rate can be derived, based on which different system parameters can be optimized. However, in these cases, the power that can be supplied by far‐field wireless transfer is still low. Thus, the chapter examines an example of using low wireless power in sensor networks.