Primary control signal bus selection for radio heads based on propagation delay

A method of operating a wireless communications system, said system comprising a plurality of physically separated radio heads cascaded in a chain and at least first and second control interfaces connected to said chain and supplying control information thereto via a plurality of virtual control signal busses connecting said control interfaces to said plurality of radio heads, including at least a first virtual control signal bus connecting said first control interface to said plurality of radio heads and a second virtual control signal bus connecting said second control interface to said plurality of radio heads, said method comprising:

• determining the propagation delay from said first control interface to a first radio head over said first virtual control signal bus;
• determining the propagation delay from said second control interface to said first radio head over said second virtual control signal bus;
• and
• determining, by said first radio head, a primary control signal bus from amongst said plurality of virtual control signal busses based on said respective propagation delays between said first radio head and said control interfaces.

A method of operating a wireless communications system, said system comprising a plurality of radio heads cascaded in a chain with buffered error correction therebetween and at least first and second control interface units connected to said chain and supplying control information thereto via a plurality of control signal busses connecting said control interface units to said plurality of radio heads, said method comprising:

• determining the propagation delay from a first control interface unit to a first radio head over a first control signal bus;
• determining the propagation delay from a second control interface unit to said first radio head over a second control signal bus;
• and
• selecting, by said first radio head, a primary control signal bus from amongst said plurality of control signal busses based on the respective propagation delays between said first radio head and said first and second control interface units.

A wireless communications system, comprising:

• a plurality of geographically separated radio heads cascaded in a chain;
• at least first and second control interfaces connected to said chain and supplying control information thereto;
• a plurality of virtual control signal busses connecting said control interfaces to said plurality of radio heads, including at least a first virtual control signal bus connecting said first control interface to said plurality of radio heads and a second virtual control signal bus connecting said second control interface to said plurality of radio heads;
• wherein said first control interface is adapted to determine the propagation delay from a said first control interface to a first radio head over said first virtual control signal bus;
• wherein said second control interface is adapted to determine the propagation delay from said second control interface to said first radio head over said second virtual control signal bus;
• and
• wherein a radio head in said chain is adapted to determine which of said virtual control signal buses is primary based on the respective propagation delays from said control interfaces to said radio head.