Use of shorted coaxial transmission line for high-power microwave measurement

In order to reduce the effective area of the receiving antenna to receive microwave power in the high electric field regions, a 1.76 GHz shorted coaxial transmission line (SCTL) is investigated numerically and experimentally in this paper. When the frequency is 1.76 GHz, the simulation results show that the general gain and the effective area of the SCTL are -10.21 dBi and 2.19 cm(2), respectively, and the power capacity of the SCTL is about 41 kW. So the maximum power flow density, which can be measured by the SCTL, is 18.7 kW/cm(2). With the frequency varying from 1.70 to 1.80 GHz, the general gain increases from -11.19 to -9.42 dBi linearly. The general gain of the SCTL is calibrated with the Agilent E8363B network analyzer in an anechoic chamber, and the calibrated results agree with the simulation. The high-power tests are performed on an improved magnetically insulated transmission line oscillator. Compared to the cutoff free-field probe, the maximum power flow density, which can be measured by the SCTL, is higher.