Porting And Development Of Embedded System For Spectrum Monitoring Network

Electromagnetic spectrum monitoring is to monitor the electromagnetic spectrum, which is a limited and non-renewable resource and it provides information for spectrum management to ensure to use the spectrum resource orderly and efficiently. With the development of wireless technology, the existing spectrum monitoring systems have been unable to adapt the spectrum monitoring requirements in the modern context. Wireless sensor network(WSN) which is based on wireless self-organized network and combined sensor technology is a new distributed data collection system with rapid development in recent years. Considering its merits of low cost, low power consumption, distribution and network self-organization, if we can fuse the WSN technology to create a new distributed wireless spectrum monitoring system, it will completely overcome the shortcoming of the traditional systems and meet the new demand of wireless spectrum monitoring. In this new system, it is not only the collection or processing of spectrum data been needed, but a strong networking ability, with witch the system can set up the network quickly and send data to server in no time. These demands must rely on the embedded system to meet, and it is a worth researching problem to port and develop a suitable embedded system for the new system.In this paper, the limitations of existing spectrum monitoring system and the characteristics of WSN are analyzed. The technical problems to combine the spectrum monitoring with WSN are studied. Accordingly we designed the network architecture of the new wireless spectrum monitoring system based on WSN and service functions of sensing node. On request, a platform is established with AT91SAM9G45 microprocessor as the digital control center and cooperates with the reception channel and network communication module. On this platform, an embedded system with Linux kernel 2.6.30, all spectrum data is generated by the reception channel which receives the electromagnetic signal. These data is expected to be sent to the task manage center after processed under the control of the operating system. This paper focuses on the porting of embedded Linux system, including the Bootloader, file system and Linux kernel. Besides, the development of drivers required by the system like FPGA and Watchdog is detailed.