Abstract: A time division duplex digital radio frame structure with time and frequency diversity and method for use thereof is presented. Each packet of data is transmitted twice in successive frequency hops, such that the redundant transmission differs in both time and frequency from the primary transmission. A communications system employing the frame structure may be configured to dynamically shift between fully diverse, asynchronous and non-diverse modes of operation. The mode of operation may be selected based upon one or more operating parameters, such as battery power or detected interference. When error correction is implemented and a primary transmission is received without error, system devices may de-power circuitry to reduce power consumption.

Abstract: A hybrid data frame is presented for a time division multiple access frequency hopping communications system. The frame includes uplink and downlink subframes, and each subframe includes a plurality of frequency hops. First frequency hops in each subframe have at least one time slot, and the first hops follow default non-adaptive frequency hopping patterns, such that unsynchronized communicating units can synchronize with the communications system during the first hops using the predetermined default pattern. The second frequency hop also includes at least one time slot, and employs an adaptive frequency hopping pattern. Once a communicating unit is synchronized to the communications system via the first frequency hop, it can be assigned to a time slot within the second hop and adaptive frequency hopping interference avoidance techniques can be implemented.

Abstract: A cordless telephone implementing using a BLUETOOTH wireless bearer is presented. A BLUETOOTH voice data structure is implemented by coding the voice data at a bitrate below 64 kb/s, such that the full number of payload bits provided by the BLUETOOTH voice data structure are not required for transmission of voice data. The packet payload is then encoded in a non-standard format to implement a robust error detection and/or correction protocol for the voice data, as well as for the provision of a low-rate data channel for transmission of information such as caller ID. Alternatively, a BLUETOOTH non-voice data structure can be employed by transmitting encoded voice data as user payload bits. The data link is then flushed each time new voice data is ready for sending by the transmitting device. If slots are available before the data link is flushed, unsuccessfully transmitted data can be automatically resent, thereby implementing time and frequency diversity.

Abstract: An apparatus for synchronizing the system clocks of wireless devices in a digital communications system is presented. A digital phase-locked loop is employed. The phase-locked loop may include a counter which is incremented by a local device system clock and latched by a frame synchronization marker received from a remote device, whereby the counter output comprises a feed forward signal. The phase-locked loop may alternatively include a counter that reflects the level of data stored in receive and/or transmit FIFO buffers. The loop output signal controls the frequency of the system clock oscillator.

Abstract: A hybrid data frame is presented for a time division multiple access frequency hopping communications system. The frame includes uplink and downlink subframes, and each subframe includes a plurality of frequency hops. First frequency hops in each subframe have at least one time slot, and the first hops follow default non-adaptive frequency hopping patterns, such that unsynchronized communicating units can synchronize with the communications system during the first hops using the predetermined default pattern. The second frequency hop also includes at least one time slot, and employs an adaptive frequency hopping pattern. Once a communicating unit is synchronized to the communications system via the first frequency hop, it can be assigned to a time slot within the second hop and adaptive frequency hopping interference avoidance techniques can be implemented.

Abstract: A cordless telephone implementing using a BLUETOOTH wireless bearer is presented. A BLUETOOTH voice data structure is implemented by coding the voice data at a bitrate below 64 kb/s, such that the full number of payload bits provided by the BLUETOOTH voice data structure are not required for transmission of voice data. The packet payload is then encoded in a non-standard format to implement a robust error detection and/or correction protocol for the voice data, as well as for the provision of a low-rate data channel for transmission of information such as caller ID. Alternatively, a BLUETOOTH non-voice data structure can be employed by transmitting encoded voice data as user payload bits. The data link is then flushed each time new voice data is ready for sending by the transmitting device. If slots are available before the data link is flushed, unsuccessfully transmitted data can be automatically resent, thereby implementing time and frequency diversity.

Abstract: An apparatus for synchronizing the system clocks of wireless devices in a digital communications system is presented. A digital phase-locked loop is employed. The phase-locked loop may include a counter which is incremented by a local device system clock and latched by a frame synchronization marker received from a remote device, whereby the counter output comprises a feed forward signal. The phase-locked loop may alternatively include a counter that reflects the level of data stored in receive and/or transmit FIFO buffers. The loop output signal controls the frequency of the system clock oscillator.

Abstract: An apparatus for synchronising the system clocks of wireless devices in a digital communications system is presented. A digital phase-locked loop is employed. The phase-locked loop may include a counter which is incremented by a local device system clock and latched by a frame synchronisation marker received from a remote device, whereby the counter output comprises a feed forward signal. The phase-locked loop may alternatively include a counter that reflects the level of data stored in receive and/or transmit FIFO buffers. The loop output signal controls the frequency of the system clock oscillator.

Abstract: A time division duplex digital radio frame structure with time and frequency diversity and method for use thereof is presented. Each packet of data is transmitted twice in successive frequency hops, such that the redundant transmission differs in both time and frequency from the primary transmission. A communications system employing the frame structure may be configured to dynamically shift between fully diverse, asynchronous and non-diverse modes of operation. The mode of operation may be selected based upon one or more operating parameters, such as battery power or detected interference. When error correction is implemented and a primary transmission is received without error, system devices may de-power circuitry to reduce power consumption.