Direct G/T Measurement for Satellite Broadcasting Receivers

A new G/T measurement method for receivers which are used for direct broadcasting from a satellite is proposed. By this method, G/T can be obtained without measuring G and T values separately. Therefore, this method, which can be called a direct method, can be adopted for the G/T measurement for integrated antennas, wherein an antenna and a receiver are unseparably combined, while the conventional method can not be adopted nder these circumstances. Besides,-o special test equipment is required for this method. This method can achieve more accurate G/T data because the result is independent from noise bandwidth or signal time response of test equipments. This paper describes the principle of the method, practical test procedure and some notes on how to avoid measurement errors. Some experimental results are also presented, which show that G/T values determined by this method agree with those obtained by the conventional method within 0.4 dB.     

Planar antennas for satellite reception

Direct broadcast satellite (DBS) reception requires a circularly polarized antenna with high gain and low axial ratio. Recently, various types of planar antennas have been studied and developed for DBS reception in the 12-GHz band. A summary is presented of properties and classification of planar antennas both commercialized and reported. The basic configurations, working principles, and performance of various planar antennas are described