Clock switching algorithm based on preferred clock source

A system for providing timing synchronization between a first Radio Equipment Controller (REC) operating on a first radio standard and a second REC operating on a second radio standard, each REC communicating with one or more multi-standard radios, comprising:

• first generator means associated with said first radio standard and second generator means associated with said second radio standard for generating a primary and secondary clock signal, each associated with said first and second radio standard, respectively;
• a clock signal detector for evaluating the quality of said primary and secondary clock signals;
• a selection controller for referencing said first and second REC to one of said primary and secondary clock signals;
• a synchronization interface to align said primary and secondary clock signals once each clock signal is determined to have said appropriate quality factors;
• and
• a clock switch to reference said first and second REC to one of said primary and secondary clock signals once said primary and secondary clock signals are aligned.

A system for maintaining timing synchronization between a first Radio Equipment Controller (REC) operating on a first radio standard and having a first synchronization source, and a second REC operating on a second radio standard and having a second synchronization source, each REC being connected and operating with one or more multi-standard radio, said system comprising:

• a multiplexer connected to said first and second REC, said multiplexer monitoring said first and second synchronization source, said multiplexer having:
• a first synchronization interface for receiving a first clock signal associated with said first synchronization source and for generating a clock signal synchronized to said first synchronization source;
• and
• a synchronization source emulator for receiving a second clock signal from said second synchronization source, said synchronization source emulator comparing and aligning a timing and frequency component of said second clock signal to that of said reconstructed synchronization source, such that said second REC can maintain timing synchronization with said first REC.

In a radio system having multi-standard mixed mode radios which are used to support combining of digital baseband from a first radio equipment controller associated with a first radio standard and a second radio equipment controller associated with a second radio standard, a method of providing redundant clock switching from a primary clock signal associated with said first radio equipment controller and a secondary clock signal associated with said second radio equipment controller, comprising the steps of:

• evaluating the quality of said primary clock signal;
• referencing said primary clock signal to said first radio equipment controller if said clock signal is determined to have appropriate quality factors;
• evaluating the quality of said secondary clock signal;
• referencing said secondary clock signal to said second radio equipment controller if said clock signal is determined to have appropriate quality factors;
• aligning said secondary clock signal with said primary clock signal if said primary and secondary clock signals are deemed to have said appropriate quality factors;
• and
• switching reference of said second radio equipment controller to said primary clock signal once said primary and secondary clock signals are aligned.