High-frequency signal booster

In a small-cell mobile radio communication system, a high-frequency signal booster for receiving, amplifying and reradiating high-frequency waves, including:

• a first antenna system for receiving first input high-frequency signals from a base station and transmitting first output high-frequency signals to the base station;
• a second antenna system for receiving second input high-frequency signals from a mobile station and transmitting second output high-frequency signals to the mobile station;
• branching means connected to said first and second antenna systems for supplying said first or second input high-frequency signal to two or more output portions thereof;
• two or more channel units, each of which is connected to a different one of the output portions of said branching means and having predetermined selectivity for performing selective amplification of the first or second input high-frequency signal, wherein at least one channel unit includes a down-converter for converting all or part of the first or second input high-frequency signal into an intermediate-frequency signal and an up-converter for converting said intermediate-frequency signal into the output signal of said one channel unit;
• combining means connected to said channel units for combining output signals of said channel units;
• and
• a common power amplifying means connected to said combining means for amplifying outputs of said combining means to increase power levels thereof and output the first or second output high-frequency signal to said first or second antenna system.

In a small-cell mobile radio communication system, a high-frequency signal booster for receiving, amplifying and reradiating high-frequency signals at the same frequency as that of the received signal, including:

• a receiving antenna for receiving input high-frequency signals;
• a transmitting antenna for transmitting output high-frequency signals;
• a down-converter connected to said receiving antenna for converting the received input signals into intermediate-frequency signals;
• an up-converter, which being connected to said down-converter and said transmitting antenna, for converting the intermediate-frequency signals into the output high-frequency signals to be transmitted from said transmitting antenna;
• first station-originating signal generators connected to said down-converter for generating first station-originating signals to be inputted to said down-converters;
• and
• second station-originating signal generators connected to said up-converter for generating second station-originating signals to be inputted to said up-converter,
• wherein the output high-frequency signals are frequency-modulated with out-of-voice-band signals before transmitted from the transmitting antenna, and
• wherein the out-of-voice-band signals are detected from the received input signals and further a gain of said high-frequency signal booster is controlled in accordance with the detected level of the out-of-voice-band signals.

In a small-cell mobile radio communication system, a high-frequency signal booster for receiving, amplifying and reradiating high-frequency waves at the same frequency as that of the signals received from a base station and a mobile station, said booster having:

• an upstream antenna for receiving first input signals sent from a base station and transmitting first output signals to the base station;
• an upstream antenna duplexer connected to said upstream antenna for accepting the receiving first input signals from said upstream antenna and sending the first output signals to said upstream antenna;
• upstream branching means connected to said upstream antenna duplexer for accepting the first input signals and supplying the first input signals to output portions thereof;
• upstream elements, each having a predetermined selectivity and connected to a different one of said output portions of said upstream branching means for selectively amplifying the first input signals accepted from said upstream branching means in accordance with the predetermined selectivity;
• upstream combining means connected to said upstream elements for combining the amplified first input signals with first synthetic signals;
• an upstream common amplifier connected to said upstream combining means for amplifying the first synthetic signals to produce the first output signals;
• a downstream antenna for receiving second input signals sent from a base station and transmitting second output signals to the base station;
• a downstream antenna duplexer connected to said downstream antenna for accepting the received second input signals from said downstream antenna and sending the second output signals to said downstream antenna;
• downstream branching means connected to said downstream antenna duplexer for accepting the second input signals and supplying the second input signals to output portions thereof;
• downstream elements, each having a predetermined selectivity and connected to a different one of said output portions of said downstream branching means for selectively amplifying the second input signals accepted from said downstream branching means in accordance with the predetermined selectivity;
• downstream combining means connected to said downstream elements for combining the amplified second input signals with second synthetic signals;
• and
• a downstream common amplifier connected to said downstream channel selecting means for amplifying the second synthetic signals to produce the second output signals,
• wherein said base station antenna is a high-gain directional antenna;
• said high-frequency signal booster further including:
• first additional elements having predetermined narrow-band selectivity for every channel for use in operation in the upstream direction in which the radio signals transmitted from said base station are amplified and reradiated;
• first relatively-narrow-band power amplifiers, each of which is connected in series to a different one of said first additional elements for further amplifying the output of said first additional elements;
• second additional elements, at least one of which has narrow-band selectivity for one channel for use in operation in the downstream direction in which the radio waves transmitted from said mobile station are amplified and reradiated;
• a second common power amplifier connected in series to said one of the second additional elements having narrow-band selectivity for amplifying the output of said second additional element.