PARTLY TUNABLE FILTER AND RADIO UNIT USING THE SAME

摘要

Embodiments of the invention provide a radio unit for use in a time division communication system, comprising: a transmitting module (210); a receiving module (220); and a filter (230) for filtering a radio frequency signal to be transmitted or received via an antenna unit (250). The filter (230) comprises a first tunable portion (231) connected to the transmitting module (210), a second tunable portion (232) connected to the receiving module (220), and a fixed portion (233) connected to the antenna unit (250). Each of the first tunable portion (231) and the second tunable portion (232) is configured to connect to the antenna unit (250) via the fixed portion (233). The first tunable portion (231) is further configured to work in a first frequency range different from a first pass band in which the second tunable portion (232) is controlled to work when the radio frequency signal is received via the antenna unit (250), such that the received radio frequency signal is rejected by the first tunable portion (231) to the transmitting module (210). The second tunable portion (232) is further configured to work in a second frequency range different from a second pass band in which the first tunable portion (231) is controlled to work when the radio frequency signal from the transmitting module (210) is to be transmitted via the antenna unit (250), such that the radio frequency signal to be transmitted is rejected by the second tunable portion (232) to the receiving module (220).