Effective capacity of wireless networks over double shadowed Rician fading channels

Recent advances in fifth-generation wireless networks demand quality-of-service (QoS) guarantees to support real-time services such as high-speed mobile networks, autonomous vehicles, and internet-of-things under delay constraints. Since the conventional ergodic capacity proposed by Shannon cannot account for QoS guarantees requirements, a new potential notion was presented to assess the performance of the wireless network in recent studies, which is called the effective capacity (EC). This paper conducts the performance analysis for EC over double shadowed Rician fading channels. To achieve this, the expression for the EC is derived in the closed-form. A truncation error of the expression for the corresponding EC is also derived, which is considerably tight. Furthermore, the consequences of channel and system parameters on the QoS performance of the wireless network are revealed by conducting an asymptotic EC analysis under the sovereignty of high signal-to-noise ratio (SNR). It is found that asymptotic bound for EC is notably tight and asymptotic EC matches with the analytical EC, when SNR is large (e.g. \(\bar{\gamma } \ge 20\) dB). Additionally, the expressions for the EC of shadowed Rician and Nakagami-q fading channels are deduced as special cases of double shadowed Rician fading. The results for these special cases show similar behaviour of EC as in case of double shadowed Rician fading channels.