Adaption Resizing Communication Buffer to Maximize Lifetime and Reduce Delay for WVSNs

Due to battery-powered wireless video sensor networks (WVSNs) takes on a high video data volume, it becomes a crucial issue to reduce energy consumption to maximize lifetime. At the same time, WVSNs are often applied to important situations for real-time and semi-real-time monitoring, thus ensuring the rapid transmission of these perceived data to sink is another critical issue. In static random-access memory (SRAM) communication buffer-based WVSN node, the radio is turned off during the data buffer-filling period as well as idle period. Because each radio transition contains the additional energy consumed by invalid packet header information and communication connection establishment, and the radio ON/OFF transition incurs extra circuit energy consumption. Therefore, from the perspective of saving energy, we need to reduce the ON/OFF transition frequency, which requires a large-sized buffer. However, the large size of SRAM buffer results in more energy consumption because SRAM energy consumption is proportional to the memory size. More importantly, the large ON/OFF transition frequency will lead to a large data transmission delay, which is harmful to applications. In this paper, an adaption resizing communication buffer (ARCB) scheme is proposed to maximize lifetime and reduce delay for WVSNs. In the ARCB scheme, the buffer size takes the minimum energy consumption optimization value in hotspot areas to maximize lifetime and takes a value smaller than the optimized value in non-hotspot areas to reduce delay. Although this consumes more energy for communication, since nodes in the non-hotspot areas have energy surpluses, it will not affect the lifetime. As a result, ARCB scheme can simultaneously increase the lifetime and reduce the delay in WVSNs. The effectiveness of the ARCB scheme is verified by theoretical analysis. The results show that the proposed ARCB scheme reduces the delay by 27.9%, and increases the effective utilization of energy by 24.1% under the condition that its lifetime is no less than previous schemes.