A Research Of Frequency Transmitter Controller Synchronized With GPS Based On PC104 Bus

With the rapid development of modern communication technology, electronic system,electronic countermeasure and reconnaissance technology, the performance of the frequency generator which is the core part of the system has been put forward higher and higher. This thesis originates from the transmitter project which is jointly developed by our lab and a military research institute. The project requires us to develop a Frequency Transmitter Controller Synchronized with GPS to provides high accuracy frequency signal for pulse power supply and communicate with it, the frequency signal can switch automatically according to the planned frequency table while the precision is good. The output frequency value is mainly some special frequency points, such as 8192 Hz, 1489.45 Hz, 46.546 Hz.Based on the analysis of the function and performance index of the transmitter controller, this thesis aims to find a solution of generating frequency which can ensure a certain frequency accuracy and can also switch the frequency points fast and automatically.This thesis use the method of counting the pulse of the high precision and high frequency signal to generate the target frequency signal. Use GPS disciplined oscillator as the system standard frequency source. Based on the analysis of the characteristic of the special frequency point, we use the PLL frequency synthesizer CDCE913 to convert standard frequency to the 24903680 Hz reference input frequency, which meets the requirement of the special frequency point. At last the CPLD logic chip output programmable frequency signal according to the count frequency constant provided by ARM and the reference frequency. In order to realize the programmable of the large-scale frequency table, using embedded computer to complete the human-computer interaction. And the above functions are designed into a PC/104 board. The planned frequency table will be putted into the Flash of the ARM through the PC104 bus.Using the method of counting pulse of the frequency to produce the other frequency signal, which makes the switch between frequency points fast and efficient. After testing,the accuracy of the reference frequency reaches7-10, which can meet the requirement of the system. By introducing embedded industrial control computer, it is possible to import and store large scale frequency table. It makes the editing and the import of the Frequencytable more convenient, and the man-machine interface become more friendly, greatly improving the efficiency of the work, and it improves the work efficiency greatly.