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A technique for time domain avoidance of communications link interference sources characterized by intermittent, periodic short bursts of energy. A transmitting source can be assigned two time slots within a time domain multiple access data frame over which each data packet can be transmitted. The t

A technique for time domain avoidance of communications link interference sources characterized by intermittent, periodic short bursts of energy. A transmitting source can be assigned two time slots within a time domain multiple access data frame over which each data packet can be transmitted. The time slots are separated by a duration greater than that of an interference burst, such that an interference burst does not affect both time slots in any given frame. Therefore, the data packet can be received on at least one of the two assigned time slots. Transmitter power consumption can be reduced by calculating the timing of the periodic interference bursts, and only transmitting a data packet on one of the two assigned time slots that will not coincide with an interference burst in each frame. Communications link capacity can be improved during the presence of interference by synchronizing the data frame to the timing of the interference bursts. The bursts then occupy fixed time slots in each data frame, enabling standard single time slot transmissions for the remaining communications channels in the data frame.

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I claim: 1. A method for transmitting information over a time duplexed communications link subject to interference from a broadband interference source, comprising: connecting a base unit communicating over the duplexed communications link to an AC power source that powers the broadband interferenc

I claim: 1. A method for transmitting information over a time duplexed communications link subject to interference from a broadband interference source, comprising: connecting a base unit communicating over the duplexed communications link to an AC power source that powers the broadband interference source; detecting a consistent timing of data packets received with errors over the communications link at regular intervals, wherein a segment B interferer is determined to be active, wherein detecting consistent timing comprises: observing a time at which the data packets are received in error, receiving phase information of the AC power source, comparing the phase information of the AC power source to the time at which the data packets are received in error, and determining that the data packets are received in error repeatedly at a consistent timing position with respect to the phase of the AC power source; switching operation of the duplex communications link to an enhanced mode, wherein active physical links between the base unit and a portable handset are assigned redundant time slots in addition to primary timeslots used for communication between the base unit and handset; and lowering a threshold for determining the segment B interferer to be active, wherein the enhanced mode is initiated after detection of a lower number of periodic errors; wherein the phase information of the AC power source is provided by an output signal of a zero crossing detector. 2. The method of claim 1, wherein the enhanced mode operation comprises: transmitting the information within a first assigned time slot of the time duplexed communications link; assigning a second time slot of the time duplexed communications link upon which a redundant copy of the information is to be transmitted, wherein a spacing between the first and the second time slot is greater than a duration of a segment B radiation burst and different than predetermined intervals between successive segment B radiation bursts; and transmitting the redundant copy of the information within the second time slot of the time duplexed communications link. 3. The method of claim 2, wherein intervals between successive segment B radiation bursts alternate between about 7 msec and about 9 msec. 4. A method for transmitting information over a time duplexed communications link subject to interference from a broadband interference source, comprising: connecting a base unit communicating over the duplexed communications link to an AC power source that powers the broadband interference source; detecting a consistent timing of data packets received with errors over the communications link at regular intervals, wherein a segment B interferer is determined to be active; and switching operation of the duplex communications link to an enhanced mode, wherein active physical links between the base unit and a portable handset are assigned redundant time slots in addition to primary timeslots used for communication between the base unit and handset, and wherein the enhanced mode operation comprises: transmitting a primary copy of a downlink data packet from the base unit to a handset within a first downlink time slot of the time duplexed communications link; assigning a second downlink time slot of the time duplexed communications link upon which a redundant copy of the downlink data packet is to be transmitted; transmitting the redundant copy of the downlink data packet within a second downlink time slot of the time duplexed communications link; receiving an uplink data packet at the base unit that is transmitted from a handset over a first uplink time slot, wherein an assignment of the uplink time slot is sent by the base unit in a message to the handset before transmission of the uplink data packet. 5. The method of claim 4, wherein the message is contained in downlink packet header. 6. The method of claim 4, wherein the handset does not transmit until receiving the assignment of the uplink time slot. 7. A system for transmitting information over a time duplexed communications link that is subject to periodic radiation bursts, comprising: a transceiver in a base unit configured to operate the time duplexed communications link in a standard or enhanced mode; an AC to AC converter coupled to an AC power supply that powers the base unit and a source of the periodic radiation bursts; a microcontroller (MCU) unit that controls operation of the transceiver, a zero crossing detector that generates a signal to the MCU for determining a frequency and polarity of the AC power source, wherein a timing of transmission errors received at the base unit with respect to a phase of the AC power source is determined; a CODEC device configured to convert digital data contained in the transmitted information into audible information; a buffer device serially incorporated into a data path of the CODEC device, the buffer configured to buffer the information for playback at a constant rate, wherein the enhanced mode comprises: transmitting a first copy of the information within a first time slot of the time duplexed communications link; assigning a second time slot of the time duplexed communications link upon which a redundant copy of the information is to be transmitted, wherein a spacing between the first and the second time slot is greater than a duration of the periodic radiation burst and different than predetermined intervals between successive segment periodic radiation bursts; and transmitting the redundant copy of the information within the second time slot of the time duplexed communications link. 8. The system of claim 7, wherein the time duplexed communications link comprises a WDCT frame structure. 9. The system of claim 7, wherein the periodic radiation bursts comprise segment B radiation bursts. 10. The system of claim 9, wherein the enhanced mode of operation is initiated when a consistent timing position of transmission errors received at the base unit with respect to the phase of the AC power source is observed. 11. The system of claim 7, wherein the information buffered into the CODEC is contained in and selected from one of the first and redundant copies of the information, the selection based on the chosen copy being received without error. 12. The method of claim 4, wherein the time duplexed communications link comprises a WDCT frame structure. 13. The method of claim 4, wherein the enhanced mode of operation is initiated when a consistent timing position of transmission errors received at the base unit with respect to a phase of the AC power source is observed.