Research On Testing Method For Direct Spurious Emission Power Measurement In Fully-anechoic Chamber

Benefiting from the rapid development of digital integrated circuits, DSPtechnology and RF modulation technology in recent years, wireless communicationproducts have spread and penetrated into every corner of human life. However, withthe R&D of new products and new technology, problems have also emerged. Likewater and mineral resources, the spectrum resources available for human use arelimited. Chinese Property Law and the Radio Management Ordinance clearlystipulates:"The radio spectrum resources are owned by the state". RF performancetests should be carried out on the products before they enter the market.However, domestic and foreign laws and regulations have not explicitly stated intest methods, standards or regulations. Traditional method for RF tests is calledpower-substitution test from which we can not get real-time measurement resultswhen doing test. It’s not macroscopic and it’s indirect and slow. It’s not compatiblewith low-repetition-rate products. What’s more, testing time is not fixed, because itdepends on the products’ emission level and over-limit points’ count.This paper is aimed to establish a new system which maintains the originalaccuracy while making up for the old system’s shortcomings. It first theatricallyanalyzed the feasibility of the configuration and test approach. Then it compareddifferent aspects of the available receiving instruments, test antennas, filters banks,pre-amplifier, etc. and overcame their limits with their advantages. Then finally asystem was setup and its performance is observed and analyzed. Results are alsocompared and uncertainties are calculated.Combining the standards’ requirements and practical experience, the topic of thispaper is how to overcome the shortcomings of traditional measurement method andthe approaches to search for improvements and even evolutional methods.Maintaining measurement accuracy the same level, it is looking forward toestablishing a fast and efficient test method and test system. We’re positive that thedirect test system will play a positive role in promoting the development of theindustry and technological innovation and in improving the professional level andeconomic efficiency of the laboratory.