Temperature compensation of VHF-band lumped-element ferrite circulator for wireless communication application

The ferrite circulators have found wide applications in many civil and military fields, such as communications, radars and so on. In this paper, except for selecting suitable ferrite material, one kind of peculiar alloy has been employed to guarantee the optimization and temperature stabilization of the ferrite circulator. The prototype based on the design considerations has been constructed; the measured data have indicated the good performance in the whole band (140 MHz-180 MHz). In addition, no obvious degradations of performances has been observed when the ambient temperature has varied over the range 0°C to 70°C, the 20 dB isolation has been guaranteed throughout the temperature range of interest.