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The low resistance of HTS materials means that HTS filters can contain many resonating elements whilst maintaining extremely low insertion losses. This allows practical HTS filters to achieve extremely sharp cutoff characteristics with insertion losses much less than conventional filters. Furthermore, low noise amplifiers (LNA) can be cryo-cooled such that they generate very little thermal noise.

As an HTS filter provides a lower insertion loss and sharper band pass profile than a conventional filter, it can be used for improving receiver sensitivity and lowering transmission output power, but the tremendous stop band attenuation can also reduce the linearity requirements of the power amplifier. Notwithstanding the above, the principal effect of placing an HTS filter on the front-end of the
base station is to achieve extremely low out-of-band emissions.

The practical performance benefit of the HTS front end derives from the extremely high stop band attenuation that is achieved. A conventional filter has relatively wide “skirts” which allows noise power from adjacent spectrum to enter the receiver chain. Non-linearities in each component of the chain (in particular the mixers, which are non-linear by design) then produce intermodulation (IM) products which may appear within the band of operation. The in-band power presented to the demodulator then comprises the wanted signal, noise and in-band IM interference. With a conventional LNA, in-band IM interference effectively desensitises the receiver, however in the case of an HTS filter being used this out of band noise can be in effect totally blocked from entering the receiver chain, so that no in-band IM interference is seen at the demodulator.