Design And Implementation Of Baseband Process SDK In IEEE 802.11ac Test Instrument

A new generation of Wireless Local Area Network standards——IEEE 802.11ac has been published. It can provide users significant raise of data rate, however, it challenges the design and test of this kind of WLAN products at the same time. Under this background, baseband process Software Development Kit in IEEE 802.11ac test instrument is designed and implemented in this thesis. The main contens are as follows.First, IEEE 802.11ac protocol and key technique in Physical Layer is introduced. After simply declaring the architecture of IEEE 802.11 ac standard, the key points in PHY including Orthogonal Frequency Division Multiplexing, Multiple Input Multiple Output and alternative short Guard Interval are focused on. Then VHT PPDU frame format which contains definitions of fields, time domain and frequency domain in IEEE 802.11ac protocol is detailed.Test items in IEEE 802.11ac are then studied. Test plan adds items for R&D on the basis of the standards, including pulse position and length, transmit power, transmit spectrum mask, spectral flatness, symbol clock frequency tolerance, center frequency leakage, transmit constellation error, occupied bandwidth, continuous wave and so on. Specification in protocol and algorithm of above-mentioned test items are emphasized.Baseband process SDK is designed and implemented. After the overview of SDK, structure and procedure are introduced. Definitions of interface layer function are then given. At scheduling layer, emphasis is on modulation accuracy module of class CAnalyse. Then a detailed description of the implementation scheme of the underlying layer is presented, including class CMyArray, class CTool, class CTimeAnalysis and class CSpectralAnalysis. Classes relating to modulation accuracy are illustrated by the example of class COFDM11ac.Test platform based on virtual instrument tests and analyses the SDK. First, software dependency and way of connection and working of the platform are introduced. Then platform is demonstrated to show the user interface. Results of SDK and Aeroflex for the test items mentioned above are compared to show the accuracy of SDK.At last, a summary and looks to the work in the future are given in this thesis.