A high-temperature superconducting (HTS) band-pass filter centered frequency at 127.5MHz was successfully designed and developed. The HTS filter is 14-pole, adopting compact symmetrical dual-spiral resonators. The filter was fabricated on a 3-inch-diameter 0.5-mm-thick LaAlO3 wafer with double-sided DyBa2Cu3O7 thin films. Through the low temperature test, the insertion loss of the HTS filter is under 0.1dB, the bandwidth is 20 MHz, the return loss is better than-22dB and the out-of-band rejection is greater than 80dB. The filters measurements agree well with the simulation.

In this paper, a 14-pole HTS filter is successfully designed and developed, which based on the reflected group delay method. The principle, design process, simulation are demonstrated. The filter is fabricated on a MgO substrate with double-sided DyBa2Cu3O7HTS thin films. The filter’s center frequency is 813.5MHz with a bandwidth of 15MHz, the return loss is better than 20dB.

A three-channel high temperature superconducting filter is designed for channelized receiver front-end systems. The principle and equivalent model of the filter has been demonstrated. There is 6-pole for each channel of the desired three-channel filter. The bandwidth of each channel is 40MHz.The simulation result is good agreement with theoretical analysis, illustrating the feasibility of this design. Such a structure of high temperature superconducting filters will have a wide application in communication fields

This paper represents a high-temperature superconducting (HTS) linear phase filter with self-equalization for WCDMA communication system. of the filter have been presented. The principle, equivalent model, theoretical result, coupling matrix, and the simulated result have been presented. The desired filter with 12-pole and 2 cross couplings has a center frequency of 1950 MHz. The measurement results show that the response of practical filters is in good agreement with that of simulated results and theoretical analysis, the group delay variation is less than ±10 ns over 75% of the filter bandwidth.