Research On Low-cost Wireless Local Area Networks For On-site Testing

On-site testing equipment, as the first hurdle for quality control of product,its stability, reliability is directly related to the final product quality. Traditionalon-site testing equipment has simple data processing and storage capabilities, butdata transmission and remote management stay in the wired connection, which havegreatly restricted the convenience of unified management. So this subject choseon-site testing equipment as the background, proposed a wireless local area network(WLAN) with low cost and low complexity, providing a series of flexible solutionsfor both data transmission and remote control of on-site testing equipment.This paper focuses on the research contents including:According to the fact that diversity, complexity and cost sensitive characteristicsare common among on-site testing equipments, starting from a general model ofon-site testing equipment, related communication demands are analyzed; from theperspective of the wireless communication unit and structure characteristics of theWLAN, the feasibility of the WLAN is analyzed, with overall program designcompleted.Detailed analysis of the network for both hardware requirements and relatedprinciples are conducted. And on this basis, the selection and design of each moduleand key devices are finished, including minimum system design, controller design,user interface design, wireless interface design, encoding and debugging moduledesign, as well as the transceiver module design for every transmission medium.Detailed analysis of the network for software requirements is conducted. Andon this basis, the code for each function module, protocol layer and secondaryinterface is finished. For each node, drivers for local modules are implemented bymodular design method, including address encoding module, data communicationmodule; for network transmission, hierarchical design method is used, which startsfrom low to high, containing physical layer protocol, transport layer protocol, andapplication layer protocol; for the secondary interface, object oriented design method is used, with a set of access control protocol implemented.On the basis of both hardware and software completion, fine-tuning andoptimization about transmission performance is conducted, including hardwarecarrier optimization, physical layer encoding optimization, transmission layer packetimprovement, and management strategy improvement, enhancing comprehensiveperformance of the WLAN.The WLAN this paper proposed, has initially solved the shortcoming thattraditional on-site testing equipment in the market don’t have capabilities of wirelesscommunication and management, while the cost matches low level testing equipment.Through a comprehensive inspection and assessment of the WLAN parameters, theindicators have reached design target, which meet the needs of users for both datatransmission and remote management.