Research On Real-time Data Transmission System Based On WiFi Environment

With the continuous improvement of modern wireless communication technology,many public places are equipped with the basic conditions for the use of wireless communication technology.The improvement of WiFi technology makes the wireless network more secure and stable,and more and more places are equipped with WiFi coverage conditions.Most public places are designed for wireless network access.With the development of wireless technology,a large number of wireless communication devices are used in public places,but the data transmission performance of many existing wireless communication devices cannot meet the demand of real-time data transmission.And the transmission rate of wireless data transmission also needs to be improved.Therefore,it is particularly important to improve the overall performance of the system by adopting the transmission rate that is suitable for the real-time channel condition to solve the problem that the wireless communication channel condition is affected by the external influence and thus has an impact on the data transmission efficiency.The purpose of this thesis is to improve the ability of the communication system to cope with the changeable wireless channel conditions in the wireless network environment,select the best transmission rate suitable for the channel conditions during the operation of the communication system,and optimize the overall performance of the wireless communication system.At first,the thesis introduces the basic principle of wireless communication technology,the application situation and shortcomings of real-time data transmission,and analyzes the data transmission algorithm widely used at present.Then,an improved efficient rate adaptive algorithm is proposed to solve the problem that the RBAR rate adaptive algorithm is incompatible with the existing network protocol and the system throughput is reduced due to the large number of control frames sent.The improved algorithm,by detecting the average throughput of the system,determines whether it is necessary to resend the control frame to change the data transmission rate to adapt to the changing channel conditions,so as to improve the performance of the system.Aiming at the problem that the RBAR algorithm modifies the control frame format,which leads to the incompatibility with the existing IEEE 802.11 protocol,a method is proposed to transfer the channel condition information through the scrambling sequence without modifying the RTS/CTS control frame format,so as to make the improved algorithm compatible with the existing communication protocol.The improved algorithm is simulated and compared with the existing classical algorithm on the NS2 platform to verify that the improved algorithm can optimize the overall performance of the communication system,and the improved algorithm is compared with the original algorithm to confirm the effectiveness and feasibility of the improved scheme.The improved algorithm and the design scheme are applied to the CC3200 module of TI company for debugging and testing of wireless data transmission,voice data input and output experiments are conducted by using the audio codec module.The experimental results show that the proposed algorithm can effectively improve the overall performance of the wireless real-time data transmission system.