Abstract: A method of digital radio communication between a central device and a peripheral device. The peripheral device transmits a repeated burst of advertising packets on a primary physical channel, each packet comprising an advertising field indicating an availability to form a connection. The advertising field comprises an address identifying the peripheral device. The peripheral device transmits a subsequent advertising packet on an auxiliary channel. The central device receives a packet from the burst of packets, decodes the advertising field and compares the address to one or more desired connection addresses to determine whether to initiate a connection to the peripheral device. If the address matches a desired connection address, the central device initiates a connection to the peripheral device. If the address does not match a desired connection address, the central device resumes listening for further advertising packets.

Abstract: A method of operating a digital radio transmitter device in accordance with a predetermined communication protocol defining a transmission timing tolerance. The method comprises: transmitting a plurality of first periodic transmissions in accordance with said predetermined communication protocol having a first period and an inherent timing uncertainty less than said transmission timing tolerance; performing a plurality of second periodic actions with a second period wherein said first and second periods are equal to each other or an integer multiple of each other; and adjusting a timing of one or more of the first periodic transmissions by an amount greater than said inherent timing uncertainty but less than or equal to a difference between said inherent timing uncertainty and said transmission timing tolerance so as to change said first period temporarily by an amount less than or equal to said transmission timing tolerance, thereby changing an offset between said first transmissions and said second actions.