Ka Band Solid State Power Synthesis Technology Research

The transmitter is a key component in satellite communications, electronic warfare, phased array radar system, and its performance will mainly depend on output capability of the final stage power amplifier. Due to the limited output power of the single chip in the millimeter-wave band, power synthesis technology is often applied to improve the output power of the transmitter.Firstly, a variety of power divider such as conventional waveguide E-T junction, waveguide magic tee,3dB branch waveguide directional coupler, novel waveguide magic tee are modeled and simulated on the basis of theoretical analysis by using3D electromagnetic simulation software CST and HFSS. We have selected the appropriate power divider structure according to the simulation results. Secondly, the spatial power divider/combiner has been researched and we have simulated a5-way space radial waveguide power divider while studied the traditional circuit synthesis power divider.On the basis of studying a variety of power dividing/combining network, this paper has researched the eight-way synthesis network in the form of binary tree based on the novel waveguide magic tee,16-way power dividing/combining network based on the H-plane3dB branch waveguide directional coupler and the novel waveguide magic tee,8-way dual-probe space power dividing/combining network on the basis of waveguide E-T junction and3dB waveguide directional coupler, and the first two synthetic networks are manufactured due to the needs of the project. In addition, the domestic power amplifier chip NC1188C-3436is installed separately in a small cavity which constitutes power amplifier module. The solid state power combining amplifiers are produced by assembling multiple separate amplifier modules and8-way and16-way power dividing/combining network. The test results show that:the average saturated output power of each basic amplifier module can achieve1.1W; the maximum saturated output power of8-way solid-state power amplifier is39.16dBm and the maximum combining efficiency is91%; the maximum saturated output power of16-way solid state power amplifier is41.51dBm and the synthetic efficiency is greater than87%, they have high synthesis efficiency and good value in engineering.