Research And Design Of Beidou Rdss Module With Small Size And Low-power Consumption

The Beidou Navigation Satellite System is a self-build and independent operational Chinses satellite navigation system serving for national security and economic and social development needs.It is an important national space infrastructure that provides all-weather,all-day,high-precision location,navigation,timing information and shot message service.With the development of the beidou system,Beidou based products has been widely used in transportation,ocean fishery,hydrological monitoring,weather forecast,surveying and mapping geographic information,forest fire prevention,communication,electric power dispatching,disaster relief,emergency rescue,etc.The beidou system gradually infiltrates human social production and all aspects of human life,injecting new vitality into global economic and social development.The Beidou system provide two kinds of service:One is Radio Navigation Satellite System(RNSS);another is Radio Determination Satellite Service(RDSS).The short message service is the characteristic distinguishing between GPS system and BDS system.The short message service is significant when natural disasters lead to the interruption of telecommunications network.For example,the spearhead which got into earthquake-stricken area first during Wenchuan Earthquake got communication with outside world using Beidou cellphone with large size.The Beidou device,especially the Beidou device with short message function is with large size which make it difficult to popularize.The large size and high-power consumption of the Beidou module with short message function is the main reason of the large size of the Beidou device.This dissertation aims to design a small size,low-power consumption Beidou RDSS module.At final the dimension of beidou device could be minimized by reducing the size of Beidou RDSS module and using small battery in help with low-power consumption module.The main research work of this paper is study and design of small size and low-power consumption RDSS module and it could divide into three parts:Firstly,this paper analyzes the structure of transmit and receiver channel of Beidou RDSS receiver,and choose the Low-IF structure based on the chactrator of the Beidou RDSS receiver.Atfer that,the parameters of transmit and receiver system have been distributed and allocated to each part.Seceondly,the paper focuses on the LNA chain which is the key part of RDSS receiver.A LNA chain which is small size,low-power consumption and suitable for portable devices is proposed.And then this paper analyzes and researches the rest of T/R channel and use MMIC to design the schematic.At final,the validity of the proposed shceme is confirmed.PCB design is completed by using Pads.After install and debug of hardware sircuit,the rdss modules go through a series of tests by using spectrum analyzer,signal generator and RDSS loop tester,and the instrument test data graph is given.It is proved that the research of this paper is feasible,the design spec is fully meet.