Point controlled energy efficient medium access in WLANs for low latency communications

Wireless networks are going through huge development due to growth in demand and supply of new wireless terminals having multiple features. Their application areas range from communication to infotainment and medical to gaming. Inclusion of large number of features make availability of sufficient power for long operational hours a key challenge in these devices. Hence, limited battery life of wireless terminals makes energy efficiency an important issue in wireless networks. Medium access control (MAC) protocols play an essential role in this context. In fact, MAC protocols can have a significant impact on energy consumption since both transmission and reception activities are very costly in terms of energy. A centralised polling based MAC avoids collisions and can guarantee a higher energy efficiency with respect to pure carrier sense multiple access (CSMA). Pointer controlled slot allocation and resynchronisation (PCSAR) protocol implements power conscious scheduling techniques to enable terminals enter prolonged sleep state, thereby improving the overall energy consumption of the network. This paper investigates the performance of PCSAR and compares it with the IEEE 802.11 standard infrastructure power save mode (PSM). Results demonstrate that PCSAR outperforms the standard mode in a composite rate WLAN scenario. Moreover, use of TDM based circuit switching makes PCSAR more reliable. These features make it a potentially good candidate for energy efficient reliable low latency communication for current (4G/LTE) and future (5G and beyond) applications.