The Design Of Maritime Communication Terminal Based On Software Defined Radio

With the continuous exploit of marine resources in the South Sea,the demand for maritime broadband communication is is rising steadily.Different from the land,the maritime frequency spectrum utilization rate is low,there are many high-quality communication frequency band can be used,but there are loopholes in the management of the maritime frequency spectrum,communication in fixed frequency bands may be disturbed by other devices that using same frequency,the communication channel will be inadvertently or intentionally occupied,affecting the communication quality.Against to the characteristics that low utilization rate of high quality maritime communication band and the lack of management of sea spectrum use,a wireless maritime broadband communication terminal based on software defined radio is designed,driving and operating software defined radio by miniaturized embedded system,achieving frequency spectrum energy sensing and broadband communication in TV white spaces.This paper designs the embedded master module based on the Linux operating system,and transplants the software defined radio driver and the GNU Radio development environment.The embedded master module connects to the software defined radio module through the USB serial port,completes the task of device driving and data reading and parameter setting,through the perception of maritime free spectrum,select the appropriate working frequency band;Using the signal processing tool in GNU Radio,the software of the file transfer program working in the blank TV band is designed by GFSK modulation mode to realize the construction of the communication link.When the radio environment changes,the terminal has the ability to adjust the communication parameters such as carrier frequency band,modulation mode,bandwidth size and radio frequency gain,so that the terminal communication link is stable and reliable;Produced a test prototype,conducted a two-way communication test experiment,the wireless broadband maritime communications terminal is able to achieve relatively accurate detection of spectrum energy and broadband half-duplex file transfer.This paper discusses the utilization of maritime free spectrum,and puts forward an effective solution to solve the spectrum guarantee of maritime wireless communication,improve the spectrum utilization rate and reduce the communication cost.In addition,this terminal provides a highly adaptable and highly flexible experimental test platform for marine communications research.