| 摘要 |
A RF paging receiver which is tunable to channels to receive pages comprising characters to be displayed with the pages being transmitted in a plurality of licensed frequency bands with each band containing a plurality of FM channels in which signal strength of pages on received channels in the bands varies as a result of variable antenna gain with programming of channels being accomplished by channel programming commands in accordance with the invention includes a tunable antenna (12, 14) having a reception bandwidth spanning the frequency bands with the antenna being tunable in response to an antenna tuning signal to achieve maximum antenna gain for a received channel in any one of the plurality of licensed frequency bands; a RF tuner (16), coupled to the tunable antenna, for receiving individual channels from the bands in response to varying a receiver tuning signal specifying reception of one of the channels within the plurality of frequency bands, the RF tuner comprising a plurality of RF amplifiers (102, 104 and 106) with each RF amplifier for amplifying channels from at least one different licensed frequency band, each RF amplifier having an operating bandwidth which is narrower in frequency than the frequency band of channels applied to the RF amplifier and which is shiftable to center the operating bandwidth within the frequency band of channels amplified by the RF amplifier on the specified channel; an IF signal processor (34), coupled to the RF tuner, for producing an intermediate frequency signal, for producing the antenna tuning signal which is a function of the level of the intermediate signal during operation of the RF tuner to dynamically tune the antenna to achieve maximum antenna gain in response to variation in the gain of the antenna in receiving a channel from any one of the channels within the frequency bands and for providing the RF amplifier tuning signal which is a function of the level of the intermediate frequency signal and the receiver tuning signal; a display (64') for displaying characters contained within a page; and a controller (24), coupled to the intermediate frequency signal, and responsive to channel programming commands, for decoding a change in at least one channel contained within a channel programming command and controlling generation of the receiver tuning signal applied to the RF tuner specifying reception of one channel specified by a received channel programming command from one of the frequency bands to cause reception of the specified channel and display of characters in pages received on the channel on the display.
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