Method and apparatus for coordinating FDX and TDD communications in a communication system

A communication controller for coordinating communications in a communication system, the communication system comprising an access node, communicatively coupled to

• a first set of remote communication units being configured to operate in a full duplex, FDX, mode via respective ones of a first set of communication lines;
• a second set of remote communication units being configured to operate in a Time Division Duplex, TDD, mode via respective ones of a second set of communication lines;
• wherein symbols transmitted on a first communication line connecting a first remote communication unit belonging to the first set of remote communication units to the access node have a first structure and symbols transmitted on a second communication line connecting a second remote communication unit belonging to the second set of remote communication units to the access node have a second structure and the symbol with the first structure and the symbol with the second structure having same symbol duration Tsymb;
• and
• the communication controller comprising at least one processor, and at least one memory including computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause the communication controller at least to:
• control that an upstream symbol with the second structure is received by the access node from the second communication line at the same time as a downstream symbol with the first structure is transmitted by the access node onto the first communication line such that a start of the upstream symbol with the second structure is aligned in time with respect to a start of the downstream symbol with the first structure.

A customer premises equipment apparatus comprising:

• at least one processor;
• and
• at least one memory including computer program code;
• the at least one memory and the computer program code configured to, with the at least one processor, cause the customer premises equipment apparatus at least to perform:
• operate in a full duplex, FDX, mode when receiving and/or transmitting signals over a first set of communication lines or operate in a Time Division Duplex, TDD, mode when receiving or transmitting signals from a second set of communication lines;
• with symbols of the FDX mode having a first structure and symbols of the TDD mode having a second structure,
• receive instructions from a communication controller for controlling operation of said customer premises equipment apparatus, such that,
• when operating in the full duplex, FDX, mode, transmitting an upstream symbol with the first structure at a reference time point trf, and
• when operating in the Time Division Duplex, TDD, mode, transmitting an upstream symbol with the second structure at tTDD_US_TX=trf−tPD2 during a time interval assigned for upstream transmission on the second communication line, wherein tPD2 is a propagation delay in said second mode and received from said communication controller.

An access node, comprising:

• at least one processor;
• and
• at least one memory including computer program code;
• the at least one memory and the computer program code configured to, with the at least one processor, cause the access node at least to perform:
• operate in a full duplex, FDX, mode when receiving and/or transmitting signals over a first set of communication lines and operate in a Time Division Duplex, TDD, mode when receiving or transmitting signals from a second set of communication lines, wherein symbols transmitted on a first communication line of the first set of communication lines have a first structure and symbols transmitted on a second communication line of the second set of communication lines have a second structure, and symbols with the first structure and symbols with the second structure have same symbol duration Tsymb;
• and
• receive an upstream symbol with the second structure over a communication line of said second set at same time of transmitting a downstream symbol with the first structure over a communication line of the first set such that a start of the upstream symbol with the second structure is aligned in time with respect to a start of the downstream symbol with the first structure.