Distributed antenna system

A distributed antenna system, comprising:

• a headend device configured to generate a downlink transmission signal by combining a plurality of downlink RF signals in different frequency bands, received from a plurality of base stations, and convert the downlink transmission signal into a downlink optical signal;
• a main remote device configured to receive the downlink optical signal from the headend device, convert the downlink optical signal into the downlink transmission signal, and amplify the plurality of downlink RF signals included in the downlink transmission signal;
• and
• a sub-remote device configured to receive the downlink transmission signal distributed from the main remote device, and amplify the plurality of downlink RF signals included in the received downlink transmission signal,
• wherein the main remote device includes a plurality of main-side band processing units cascade-connected to each other to transmit the downlink transmission signal from a front end to a rear end thereof, the plurality of main-side band processing units each amplifying a downlink RF signal in a corresponding frequency band among the plurality of downlink RF signals included in the downlink transmission signal.