Research And Implementation Of Low-power WiFi System Based On Sora Platform

Recently, Wireless LAN has been widely used and Software Defined Radio isdeveloping rapidly. As a result, the Para, SFF and Sora SDR arises at the historicmoment. This paper is based on the Sora platform with2.4G band, and WiFi physicallayer is cutted to obtain a low-power WiFi communication system. The system isused in such scenes as medical treatment, household, monitoring with the advantagesof low-power communication. The system is based on OFDM modulation technologyand the physical layer header uses1/2repetition coding. In the scenes of normalcommunication, the system compeles the transmission with low power consumption.To reduce the complexity of the receiver and achieve low power consumption,the following three aspects are studied in this paper.Firstly, this paper introduces the design of physical layer. It includes the controlinformation such as frame structure, transmission rate, and modulation scheme. At thetransmitting end, interleaving coding and convolution coding are removed, and theframe structure and transmission rate are fixed to facilitate the synchronization at thereceiving end.Compared to traditional protocol, we combine carrier sense withfrequency offset estimation together based on short preamble at the receiving end andsymbol and phase synchronization are based on long preamble. These measures canreduce the complexity of the receiver and power consumption.Secondly, this paper introduces the software design of the low-power systembased on Sora. Sora is a reconfigurable software radio platform based on commercialPC, which consists of high-performance SDR and commercial PC. This partintroduces hardware components and system structure of Sora. Then, according togeneration process of the frame structure at the transmission end and synchronousdemodulation sequence at the receiving end, the paper gives specific algorithmanalysis and software implementation about each module; moreover it givesprogramming flowcharts.Finally, the paper tests the performance of the low power WIFI system. At first, a number of test points are set to test all the modules of the emission process andreceiving process. For each module, we give it a standardized data input, then we canget a actual output and compare the actual output with standardized output to verifythe correctness of the module. In the actual environment, the performance ofbaseband physical layer as a whole are tested and we take the packet loss rate, packeterror rate and bit error rate as performance indicators.