A communication device comprising: an antenna ; a front-end switching circuit electrically connected with the antenna ; a transceiver ; a transmitting amplifier configured to amplify an output signal from the transceiver ; a plurality of duplexers or a quadplexer electrically connected between the front-end switching circuit and the transceiver ; a plurality of back-end switching circuits including a first back-end switching circuit and a second back-end switching circuit , wherein the first back-end switching circuit and the second back-end switching circuit are electrically connected between the plurality of duplexers or the quadplexer and the transceiver ; and a plurality of receiving amplifiers including a first receiving amplifier and a second receiving amplifier , the first receiving amplifier electrically connected between the first back-end switching circuit and the transceiver , and the second receiving amplifier electrically connected between the second back-end switching circuit and the transceiver ; and wherein, with respect to an input signal received via the antenna , a first connection and a second connection between the antenna and the transceiver are simultaneously provided, the first connection to be established using the front-end switching circuit , a first portion of the plurality of duplexers or the quadplexer , the first back-end switching circuit , and the first receiving amplifier , and the second connection to be established using the front-end switching circuit , a second portion of the plurality of duplexers or the quadplexer , the second back-end switching circuit , and the second receiving amplifier . an antenna ; a front-end switching circuit electrically connected with the antenna ; a transceiver ; a transmitting amplifier configured to amplify an output signal from the transceiver ; a plurality of duplexers or a quadplexer electrically connected between the front-end switching circuit and the transceiver ; a plurality of back-end switching circuits including a first back-end switching circuit and a second back-end switching circuit , wherein the first back-end switching circuit and the second back-end switching circuit are electrically connected between the plurality of duplexers or the quadplexer and the transceiver ; and a plurality of receiving amplifiers including a first receiving amplifier and a second receiving amplifier , the first receiving amplifier electrically connected between the first back-end switching circuit and the transceiver , and the second receiving amplifier electrically connected between the second back-end switching circuit and the transceiver ; and wherein, with respect to an input signal received via the antenna , a first connection and a second connection between the antenna and the transceiver are simultaneously provided, the first connection to be established using the front-end switching circuit , a first portion of the plurality of duplexers or the quadplexer , the first back-end switching circuit , and the first receiving amplifier , and the second connection to be established using the front-end switching circuit , a second portion of the plurality of duplexers or the quadplexer , the second back-end switching circuit , and the second receiving amplifier . <EOS>