Design And Implementation Of Human-computer Interaction System For Program-controlled Signal Source Of Missile-borne Telemetry System

During the missile development process,the working parameters of each component during the missile test flight are often obtained through the missile-borne telemetry system to evaluate the performance of the missile and provide strong support for the missile upgrade.In order to reduce the cost of research and development and obtain more accurate test data,the automatic test system of missile-borne telemetry system cannot be replaced.The portable 128-channel program-controlled signal source of the missile-borne telemetry system developed in this thesis is mainly responsible for providing analog excitation to the telemetry coding module and calibrating the analog channel,which is exactly applied in this automatic testing system.By combining the upper computer with the lower computer and cooperating with software and hardware,the lower computer of the signal source consists of 16 Direct Digital Frequency Synthesis(DDS)boards,each of which is divided into Field Programmable Gate Array(FPGA)module,digital-to-analog conversion module,communication module,switch module,filtering and amplifying module,DC/DC power supply module,etc.with each DDS board having an independent address,which can output up to 8 waveform signals.At the same time,it is necessary to adopt measures to achieve electrical isolation to prevent crosstalk between signals.In view of the problem that the power consumption of DDS chip increases and the reliability decreases due to the large storage space overhead,this thesis designs a ROM storage space compression optimization algorithm of DDS waveform generator on FPGA,which can compress the ROM by reducing the bit width of waveform data by storing the relative increment of amplitude sequence without changing the waveform accuracy,and restore the real amplitude sequence through the amplitude accumulator.In Quartus II 13.0development environment,the algorithm uses Verilog hardware description language to write with test pass.The results show that this DDS optimization algorithm can reduce the system power consumption and improve the system running speed.which saves more than 96% of resources than the traditional DDS waveform generator.Using the " Microsoft Foundation Classes(MFC)Intelligent Device Application Program" under VS2008,the upper computer software can control the lower computer DDS board to output the specified waveform with the function of historical readback,which can run independently under Win CE 6.0 embedded operating system.The user configures relevant information on the upper computer operation interface.After clicking the "Apply" button,the configuration information is converted into data packets in accordance with the format of the communication protocol and sent to the lower computer DDS board instruction receiving end.After analysis and identification,the user can control the DDS board.At the same time,the user configuration information is saved in the form of a text file,which is convenient for subsequent repeated use.By using touch screen to get rid of the limitation of physical keys,the upper computer has good human-computer interaction performance.The upper computer and the lower computer use RS232 to RS485 serial communication to realize instruction transmission.The finished product was tested with an Agilent oscilloscope,and the discrete waveform data points read by the oscilloscope were fitted with MATLAB.The fitting results were compared with the waveforms displayed by the oscilloscope,thus proving the correctness of the results.With the successful development of the portable 128-channel program-controlled signal source for the missile-borne telemetry system at present,six waveforms including sine wave,triangular wave,sawtooth wave,sawtooth wave,square wave with adjustable duty cycle and direct current signal can be generated,among which the amplitude adjustment range is-35～+35V,the frequency adjustment range is 0～8KHz,the duty cycle adjustment range is 0～100%,and the output accuracy is less than 0.1%FS,which has been applied to the automatic test system for the missile-borne telemetry system.