The Development Of High Speed Satellite Payload Data Simulator

Payload of satellites is expensive, easily damaged and is one of thesubsystems which costs most of the time. To avoid damaging the payload whenfrequently testing and debugging the data transmitting subsystems on the ground,there is an urgent need to design a high-speed payload data source simulatorwhich can output data and timing which is compliant with satellites in orbit.On the basis of analyzing the loading speed, capacity, sending rate andboard size, we develop a payload simulator based on PXIe×4interface and SLCNAND Flash array.In hardware design, this thesis use Xilinx’s Virtex-5family FPGA integratedPCIe hard IP core and supporting DRP as the core control device; data storageunit is divided into4relatively independent storage area and each consists of4SLC NAND Flash components making the total capacity reaching128GB so itcan provide continuous stream for24-channel LVDS. As a result of universaldesign, by replaceing larger capacity Flash devices, the total storage capacity canbe expanded to TB magnitude.In firmware design, we design4generic NAND Flash controller. Parallelcontrol of4independent channels makes the reading and programming ratesincreased4-fold. Under the control of PXIe DMA engine, we have realized4-channel high speed and large capacity data loading. The use of42MB-capacitySRAM ping pong unit solves the mismatch of PXIe interface and Flashprogramming speed.In software design, we design simulator software architecture based onWindows XP. The architecture consists of three levels: the underlying PCIedriver, founction libraries and applications. For these three levels, we develop asoftware program from bottom to top.We have tested and analysised all kinds of technical indicators. The resultsshow that the high-speed simulator can continuously load image at85MB/s andoutput4channel Ka-band maximum300Mbps data stream.The achievement has been applied to the actual remote sensing satellite’sground tesing. The application results show the high-speed simulator has a good versatility and flexibility to meet the ground data transmission subsystem’sdebugging and testing requirements.