A demultiplexing apparatus comprising: a demultiplexed-signal selecting and distributing unit configured to output one or more input signals to one or more output destinations designated by a predetermined control signal; a reception low-pass filter group including frequency converting and reception low-pass filter units (101 to 114) configured to apply frequency conversion processing and down-sampling processing to an output signal of the demultiplexed-signal selecting and distributing unit, the frequency converting and reception low-pass filter units (101 to 114) being arranged in a tree shape, and at least a part of the frequency converting and reception low-pass filter units (101 to 114) dividing the output signal into two and inputting the divided output signals to two frequency converting and reception low-pass filter units (101 to 114) at a next stage; and characterized in that: the demultiplexing apparatus further comprises a selector unit (133 to 136), configured to switch, based on the control signal, an input source of a signal input to one of the frequency conversion and reception low-pass filter units (101 to 114) between i) the demultiplexed-signal selecting and distributing unit; and ii) a preceding frequency converting and reception low-pass filter unit (101 or 102) at a preceding stage of the frequency converting and reception low-pass filter units (103 to 106), wherein the demultiplexed-signal selecting and distributing unit changes a conversion amount of a frequency in the frequency conversion processing and a level of down-sampling in the down-sampling processing based on an arrangement position of the frequency converting and reception low-pass filter units (101 to 114) set as an output destination and a bandwidth of a signal. a demultiplexed-signal selecting and distributing unit configured to output one or more input signals to one or more output destinations designated by a predetermined control signal; a reception low-pass filter group including frequency converting and reception low-pass filter units (101 to 114) configured to apply frequency conversion processing and down-sampling processing to an output signal of the demultiplexed-signal selecting and distributing unit, the frequency converting and reception low-pass filter units (101 to 114) being arranged in a tree shape, and at least a part of the frequency converting and reception low-pass filter units (101 to 114) dividing the output signal into two and inputting the divided output signals to two frequency converting and reception low-pass filter units (101 to 114) at a next stage; and characterized in that: the demultiplexing apparatus further comprises a selector unit (133 to 136), configured to switch, based on the control signal, an input source of a signal input to one of the frequency conversion and reception low-pass filter units (101 to 114) between i) the demultiplexed-signal selecting and distributing unit; and ii) a preceding frequency converting and reception low-pass filter unit (101 or 102) at a preceding stage of the frequency converting and reception low-pass filter units (103 to 106), wherein the demultiplexed-signal selecting and distributing unit changes a conversion amount of a frequency in the frequency conversion processing and a level of down-sampling in the down-sampling processing based on an arrangement position of the frequency converting and reception low-pass filter units (101 to 114) set as an output destination and a bandwidth of a signal. i) the demultiplexed-signal selecting and distributing unit; and ii) a preceding frequency converting and reception low-pass filter unit (101 or 102) at a preceding stage of the frequency converting and reception low-pass filter units (103 to 106),