Design of power saving protocol with duty cycle adjustment for public safety-LTE

Abstract

In this paper, a power saving protocol for public safety-long-term evolution (PS-LTE) with duty cycle adjustment is proposed according to the emergency of PS-LTE-based mobile stations. Because the PS-LTE transceiver consumes power whenever it is active, it is the most efficient to leave the receiver off, and wake it up asynchronously only when needed. As an alternative to protocol-based duty-cycle control, an asynchronous wake-up scheme is designed for battery saving of PS-LTE devices. This type of PS-LTE phones with power saving protocol has an adaptive cycle control during 'EMERGENCY-CALL'. This dedicated wake-up 'EMERGENCY PS-LTE Phone' can continuously monitor the channel, listening for a wake-up signal from other nodes and activating the main receiver upon the detection of asynchronous wake-up protocol. As a result, PS-LTE-based mobile station reduces power consumption by maximising the node sleeping-time without compromising network latency, and the wake-up PS-LTE phone with power saving protocol (without PS-LTE's function activities: group communication systems enabler, proximity-based service, mission critical push-to-talk, isolated E-UTRAN operation for public safety, relay, etc.) also enables the improvement of overall network performance.