| 摘要 |
This application relates to a frequency conversion device 14 which includes a first connector 52 for connecting to a conventional terrestrial radio transceiver 10, and a second connector 36 for connecting to a satellite antenna 16. The radio transceiver preferably operates at UHF or VHF frequencies, and the satellite antenna preferably operates in the L-band. The frequency conversion device performs UHF/VHF to L-band upconversion to enable signals from the radio transceiver to be transmitted to a satellite, and performs L-band to UHF/VHF downconversion to enable signals from a satellite to be received at the radio transceiver. The frequency conversion device contains a frequency converter 40 which switches between transmit and receive modes. The frequency converter by default operates in a receive mode, unless the frequency conversion device detects 42 a transmit signal from the radio transceiver, in which case it operates in a transmit mode. The frequency conversion device may monitor temperature or antenna current or voltage, and activate a warning if one of these parameters falls outside a predetermined range. |
