A filter is a device or process that removes some unwanted component or feature from a signal. Its defining characteristic is the complete or partial suppression of some aspect of a signal. In some precision measurement situations, harmonics near the carrier need to be filtered out; since the harmonics are symmetrically distributed, this requires extremely narrow-band bandpass filters. In the frequency band above 5G, it is extremely difficult to obtain 3dB bandwidth within 1MHz by traditional means.

      Tianqiong Electronics has recently launched the first set of extremely narrowband sapphire dielectric filter TQSR-F10 in China, which can obtain a 3dB bandwidth of less than 200kHz in 8~12G to meet the demand for near-end harmonic filtering.

      The core component of TQSR-F10 is a high quality factor sapphire resonator, which is thermostatically controlled with high sensitivity, and the internal core temperature can be adjusted through the serial port. The oscillator has a form factor of 85*85*60mm, a center frequency of 8~12GHz, a 3dB bandwidth of <200kHz, and an interpolation loss of <9dB. The filter can be applied to microwave band harmonic filtering, and it can be used in the fields of precision physical measurements, wireless probes, satellite communications, and meteorological radar.