Due to the satellite navigation using the frequency for the L, S band, satellite landing signal is weak, receiving terminal with wide beam antenna. Therefore, we must in no occlusion of the open area of the user terminal in order to work properly. Forwarding function of the system is the satellite signal from the outdoor to indoor or other does not receive the satellite signal, indoors with regular satellite receiver (including antenna) to receive the satellite signals, complete testing machine, the system debugging and award.

After 10 years of development, satellite signal forwarding system types of products has become increasingly rich and colorful, covering the GPS, GLONASS, BD and number of satellite application systems, has accepted by the vast number of users of the satellite terminal developers and users, as navigation products R & D, standard equipment production, marketing and other aspects, especially the mobile phone has been gradually integrated GPS function, correct assessment of the GPS receiver is a paid more attention to the topic.

The application level of existing forwarding system are relatively low, can not really simulate the actual state. The satellite signal repeater will receive the signal amplification to large enough, then the transmitting antenna to the satellite signal to the region, as long as the forward signal is higher than the satellite landing signal strength, the user can work normally. The receiver due to forwarding the signal is often large, covered the receiving signal noise part of the receiver is poor, which lead to "excessive forward" phenomenon: even in the laboratory through the inspection, the actual closing star while working in the field, the effect is not ideal. In three the main causes of this phenomenon is: as in the forwarding system research and development users are forwarding mechanism and system as the satellite signal amplification, a simple process of forwarding, is the direct cause of the problem; the simple forwarding system The system can solve some engineering requirements well, and the forwarding system of real signal is a complicated and costly project.

In recent years, with the application level enhancement, overcome the excessive forward demand is increasing, some foreign R & D institutions also launched a "real forward primary equipment, in the repeater antenna integrated signal strength detection, automatic gain adjustment function, but through the analysis, these devices no from the fundamental to achieve" true forward. This paper is in 10 years of forwarding equipment research and development based on and on "real forwarding equipment design aspects were studied. The use of" real forward system, including user receiver antenna, comprehensive, real test.