| Multi channel carrier router is a terminal which communicated by RS-485, low voltage power line and wireless to transmit data and exchange information. Among them, the low voltage power line carrier(PLC)communication module is designed and other communication module are integration. At present, in remote meter reading system, PLC communication technology and wireless communication technology has occupied 95% market share, on many occasions has been widely used. It is wirelessness, compared with the traditional RS-485 cable, reflecting the strong adaptability, low cost, flexible networking etc.Compared with single channel communication equipment, it has advantages of long transmission distance, no wiring construction, strong adaptability and other characteristics. On the market at present, there is no used in centralized meter reading system of such equipment.At the beginning of this paper,the power line carrier communication technology and wireless communication technology in the application of low-power centralized meter reading are introduced. Then, I analyzed the low voltage power line carrier communication, and wireless communication transmission characteristics based on the theory of channel transmission and found out the suitable method to transmit information from the time domain and frequency domain. Channel model is established on the basis of some modulation method introduced, including the OFDM,FSK, etc. According to the characteristics of the signal modulation technology, combined with the actual situation of engineering application,,realized power line carrier signal transmission by FSKmodulation technology.It is of 130 kHz narrowband carrier center frequency. It's receiver sensitivity is not less than 75 db and in the case of40 dB band interference, the success rate of communication more than 97%.To test for the above parameters, compared with similar products and get the conclusion to improve the performance of the whole system. |
PDF Full Text Request