Research And Implemetation ORFS Test Optimization

Nowadays, the requirement of data transferring rate is improved, GSM which played an important role in old mobile communication system is facing a big challenge due to lower data rate. But with the support of EDGE (Enhanced Data rate for GSM Evolution), GSM comes back to life. With EDGE, GSM system becomes new 2.75 generation which has much higher data rate compare to GSM only in the old time. Even the 3 generation is popular now; GSM with EDGE is still competitive. In GSM and EDGE test list, ORFS (Output RF Spectrum) is an important one which is similar with ACPR (Adjacent Cannel Power Ratio) test in CDMA (Code Division Multiple Access). Test time reduction becomes more and more critical as test cost is directly related to the time each product stays on the tester.This thesis is based on a real case of GSM and EDGE transceiver test, firstly we will what the ORFS test is then we will focus on current test time and test solution analysis, then provide a new test solution to reduce test .The optimized test solution is base on DSP window technique. The paper covers the characters of windows and how to choose them for application. Bringing the window also brings some issues in later signal power calculation, later the paper point out a new way to solve the issues. What’s more, the setup of sampling is impossible to meet the requirement of FFT for two piece of modulated signal. DFT is very slow for larger number of sample points in calculation compare to FFT. The paper gives a new way to meet the FFT requirement but not lose any accuracy of test result. At the end of this paper, a real online data are given to verify the optimized test solution. We also pursued customers to use this new test solution in mass production test. This test time reduction solution also applies in some analog tests especially for the analysis of modulated signal. Now the solution is verified in IC production test.