Spectrum Sharing Network With Wireless Energy Harvesting at Finite Blocklength Regime

In this paper, a spectrum sharing communication system with wireless energy harvesting is investigated at finite blocklength regime over Rayleigh quasi-static block-fading channels. We analyze the error probability and average delay of the secondary user (SU). The closed-form approximations for the SU error probability and average delay are derived, as functions of the number of channel uses in its information transfer phrase. Under the error probability constraint of the primary user (PU), we investigate the power constraint on the SU. Meanwhile, the error probability and energy supply constraints on the SU are also explored. Numerical results demonstrate that the approximation is very tight for a wide range of signal-to-noise ratio (SNRs). The existence of an optimum number of channel uses for SU information transfer is also verified. Moreover, under the error probability constraint of PU, the SU maximum transmit power is validated to increase with the length of an entire block. In addition, for a given target error probability, we show that the SU error probability constraint can be satisfied within the boundary numbers of channel uses in its information transfer phrase. Finally, the energy supply probability is shown as the harvested energy in each channel use with independent and exponential distribution.