Time-division duplexing (TDD) in distributed communications systems, including distributed antenna systems (DASS)

A communication system capable of supporting time-division duplexing (TDD), the communication system comprising:

• a unit configured to receive a plurality of downlink signals;
• a plurality of remote units coupled to the unit by an optical fiber infrastructure, each remote unit configured to receive optical downlink signals from the unit, and to return optical uplink signals to the unit;
• and
• a control circuit for controlling TDD switching in the communication system, the control circuit comprising:
• a first power detector configured to determine a first power level;
• a second power detector configured to determine a second power level from an uplink path;
• a receive/transmit comparator coupled to the first power detector and to the second power detector, wherein the receive/transmit comparator compares the first power level to the second power level to provide an indication indicating when the first power level exceeds the second power level;
• and
• a transmit power comparator configured to determine whether the first power level exceeds a reference value and provide an indication indicative of whether the first power level exceeds the reference value,
• wherein the control circuit is configured to determine if the communication system should be switched to TDD transmit mode or TDD receive mode based at least in part on the received indication from the receive/transmit comparator and the received indication from the transmit power comparator.

A communication system capable of supporting time-division duplexing (TDD), the communication system comprising:

• a unit configured to receive a plurality of downlink signals;
• a plurality of remote units each configured to receive downlink signals from the unit and to return uplink signals to the unit, each remote unit comprising at least one electrical-to-optical converter and being configured to transmit wireless communications into a coverage area and receive wireless communications from client devices in a coverage area;
• and
• a control circuit for controlling TDD switching in the communication system, the control circuit comprising:
• a first power detector configured to determine a first power level;
• a second power detector configured to determine a second power level from an uplink path;
• a receive/transmit comparator coupled to the first power detector and to the second power detector, wherein the receive/transmit comparator compares the first power level to the second power level to provide an indication indicating when the first power level exceeds the second power level;
• and
• a transmit power comparator configured to determine whether the first power level exceeds a reference value and provide an indication indicative of whether the first power level exceeds the reference value,
• wherein the control circuit is configured to determine if the communication system should be switched to TDD transmit mode or TDD receive mode based at least in part on the received indication from the receive/transmit comparator.