A transmit and receive integrated assembly (TRIA) is used on a two-way satellite dish to process signals to and from a ground based system and an earth-orbiting satellite. The TRIA is the part of the antenna which contains both the feed horn and the circuits which convert high-frequency satellite signals such as X-band, Ku-band and Ka-band to and from the L-band microwave signals used for transmission between the dish and the customer-premises equipment.
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Transmit and receive integrated assembly Wikipedia(Text) CC BY-SA