Research On Key Techniques Of Radio Resource Allocation In Relay-enhanced Cellular Networks

The signal generator is one kind of electronic device which is used to generate standard signal of specific parameters required for the circuit under test. It’s one of the most widely used and important electronic equipment in electronic measurement field.With the continuous advances in computer and microelectronics technology, DDS Direct Digital Synthesizer technology has become the trend of design of high-performance digital signal generator, which is with high accuracy, stability and other characteristics. Under the continued rapid development of network technology, LAN-based LXI instrument has also been developed and applied vigorously.This paper is about the design of class C LXI digital signal generator which is based on BF531 DSP processor and DDS technology. In this paper, the LXI signal generator designed primarily by the firmware and LXI communication interface module two parts. From the software design perspective, this paper elaborates the software design and implementation process of signal generator. Firmware includes the basic configuration and communication interface on BF531, logic design of human-computer interface, serial communication port and SPI control keyboard that the design is based on CPLD EPM240T100C5. Hardware platform of LXI communications module is based on the DM9000 embedded processor chip, and the software part is to port embedded uip stack and application, which includes VXI-11, ONC / RPC protocol, Portmap, SCPI parser and webserver and so on. At the end of papar, the entire system functionality testing is performed.This paper is the summary about results of software design, and put forward some ideas and plans for further research and function.