Power saving protocol for TDMA multi-line wireless telephone handsets
First Claim
1. A wireless telephone system, comprising:
- a base unit having a base transceiver; and
one or more wireless handsets, each handset comprising;
a handset transceiver that establishes a time-division multiple access (TDMA) link over a shared RF channel with the base unit via the base transceiver in accordance with a TDMA epoch divided into data and audio packet time slots which are allocated to each handset, wherein each handset may be in one of an operational mode and a sleep mode, a clock;
counters; and
a timer;
the clock, counters and timer remaining operational when the handset transceiver is powered off, the clock and counters maintain synchronization between the handset and the base unit, wherein when the handset is in the sleep mode, the handset powers on its transceiver in response to the timer, only during its respective receive data time slot of every Nth epoch, to receive a data packet and to re-synchronize the clock with the base unit using synchronization data contained in the received data packet;
while in the sleep mode, after receiving the data packet and after re-synchronizing the clock the handset transmits a data packet to the base unit during the next transmit data time slot for the handset to notify the base unit that the handset is still synchronized with the base unit, the handset being operable to maintain synchronization with the base unit, the clock and counters over a time period lasting at least N epochs without receiving synchronization data from the base unit.
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Accused Products
Abstract
A wireless telephone system comprises a base unit having a base transceiver, and one or more wireless handsets, each handset comprising a handset transceiver. Each handset establishing a time-division multiple access (TDMA) link over a shared RF channel with the base unit via the base transceiver in accordance with a TDMA epoch, which allocates exclusive data and audio packet time slots to each handset. Each handset powers on its transceiver during its respective data and audio packet time slots as necessary to synchronize with the base unit using synchronization data transmitted with a data packet, to detect incoming call data transmitted with a data packet, or to transmit and receive audio information over the TDMA link. The handset powers off its transceiver otherwise during the epoch to minimize handset power use.
83 Citations
16 Claims
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1. A wireless telephone system, comprising:
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a base unit having a base transceiver; and
one or more wireless handsets, each handset comprising;
a handset transceiver that establishes a time-division multiple access (TDMA) link over a shared RF channel with the base unit via the base transceiver in accordance with a TDMA epoch divided into data and audio packet time slots which are allocated to each handset, wherein each handset may be in one of an operational mode and a sleep mode, a clock;
counters; and
a timer;
the clock, counters and timer remaining operational when the handset transceiver is powered off, the clock and counters maintain synchronization between the handset and the base unit,wherein when the handset is in the sleep mode, the handset powers on its transceiver in response to the timer, only during its respective receive data time slot of every Nth epoch, to receive a data packet and to re-synchronize the clock with the base unit using synchronization data contained in the received data packet;
while in the sleep mode, after receiving the data packet and after re-synchronizing the clock the handset transmits a data packet to the base unit during the next transmit data time slot for the handset to notify the base unit that the handset is still synchronized with the base unit, the handset being operable to maintain synchronization with the base unit, the clock and counters over a time period lasting at least N epochs without receiving synchronization data from the base unit. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 13)
the epoch has a plurality of transmit and receive data row pairs, one such row pair for each handset; and
each handset, when in operational mode, receives and transmits data packets via receive and transmit data packet slots only once during each epoch, during the transmit and receive data row pair for each said operational handset, and receives and transmits audio packets during allocated audio time slots of the epoch for the handset.
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9. The system of claim 1, wherein:
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each handset is always in a state within one of the following layers;
an inactive layer;
an initialization layer, a standby link layer, and an active link layer;
the inactive layer occurs when the handset is out of contact with the base unit;
the initialization layer occurs as a TDMA link is being established between the handset and the base unit;
the standby link layer occurs when the base unit and handset have obtained synchronization lock, and comprises the sleep mode; and
the active link layer occurs when there is active audio communication between the handset and the base unit and comprises the operational mode.
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13. The system of claim 1, wherein N is selected so that the handset is able to maintain synchronization with the base unit with the clock and cascade of counters over a time period lasting at N epochs without receiving synchronization data from the base unit and also so that the handset is able to perform real-time call monitoring by detecting incoming call data transmitted with a data packet.
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10. A wireless telephone system, comprising:
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a base unit having a base transceiver; and
one or more wireless handsets, each handset including a handset transceiver for establishes a time-division multiple access (TDMA) link over a shared RF channel with the base transceiver according to a TDMA epoch divided into data and audio packet time slots allocated to each handset, each handset being in one of an operational mode and a sleep mode and including a clock, counters, and a timer;
the clock, counters and timer remaining operational when the handset transceiver is powered off, and the clock and counters maintaining synchronization between the handset and the base unit,wherein during the sleep mode the handset transceiver is powered and responsive to the timer during its respective receive data time slot of every Nth epoch to receive a data packet and to re-synchronize the clock with the base unit using synchronization data contained in the received data packet and after receiving the data packet and after re-synchronizing the clock the handset transmits a data packet to the base unit during the next transmit data time slot for the handset to notify the base unit that the handset is still synchronized with the base unit. - View Dependent Claims (11, 12, 14, 15, 16)
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Specification