Development Of Ku - Band Up - Conversion Module

Currently, microwave takes extremely important place in the fields of military and commercial wireless communication, radar and so on. For the increasing demand of application and the increasing tension of spectrum resources, we need the higher performance of the microwave communication system. The upper-converter, as the main part of the transmitter, its performance directly affects the performance of the whole communication system. This paper mainly designed a Ku band upper-converter module.The quotas of the Ku band upper-converter are as follows: ① Input frequency: 375MHz-225MHz; Input power:-30dBm. ② Output frequency:15925MHz-16075MHz; output power:(20±1)dBm. ③ Output power Flatness:≤1dB. ④ Phase noise:≤-70dBc/Hz@1k (single frequency test). ⑤ Spurious suppression:≤55dBc. ⑥ Attenuation range:0～100dB, 10dB step, when the attenuation value≤50dB,the attenuation accuracy≤ ± 1dB, when the attenuation value≥50dB,the attenuation accuracy≤±2dB.The main work of this paper is as follows:(1) First, the development of RF upper-converter at home and abroad is briefly introduced. Then according to the quotas of the up-converter, we made the design of twice up-convert, and distribute the quotas to each part of the system.(2) And then designs the first up-convert circuit, first local oscillator circuit, the second up-convert circuit, second local oscillator circuit in order. In the circuit, the devices that are used such as amplifiers, mixers and attenuators are selected. Then we use the ADS2009U1 and HFSS software to design the LC filter and the comb filter.(3) Use the ADIsimPLL to simulate the first and second phase locked loop, get the best phase detector frequence and loop bandwidth. And the PLL register is also configured.(4) Use the Protel DXP to design the circuit schematic and the PCB, use the Auto CAD to design the structure of the module.(5) To assembling and welding the printed circuit board, then we debug and test the module.Finally, the development of the Ku band upper-converter has completed successfully. The test results are as follows:output frequency:16075MHz～15925MHz, output power range:19.7-20.6dBm;power Flatness≤ 1dB;phase noise:-85dBc/Hz@lk;spurious suppression ≤56dBc;attenuation value≤50dB,the attenuation accuracy≤±1ldB.when the attenuation value≥50dB,the attenuation accuracy ≤±dB.All the quotas meet the requirements.