Self-supporting simplex packets
First Claim
1. A method of decoding a packet that does not include a preamble of known bit values, comprising:
- at a device configured to decode the packet;
despreading the packet using a spreading code,identifying a header of the packet that includes a sequence of bit transitions,identifying a body of the packet that includes information that has been transmitted by a transmitter, wherein identifying the header includes identifying a start of the packet based on the sequence of bit transitions,determining a first bit transition rate based on transitions in the header,identifying an end of packet sequence,determining a second bit transition rate based on transitions in the end of packet sequence, andestimating a bit transition rate for decoding bits in the body of the packet based on the first and second bit transition rates.
3 Assignments
0 Petitions
Accused Products
Abstract
Existing message fields and/or message parameters are configured to facilitate the packet and message synchronization and decoding tasks that conventionally rely upon a known bit sequence in each packet, thereby eliminating the need for a predefined message preamble in each packet. In example embodiments, the unique identifier of each transmitter is structured to facilitate determination of bit polarity and the start of each packet; packet sequence numbers use an unconventional counting sequence to assure synchronizing bit transitions; and so on. Other techniques, such as the use of run-length limited (RLL) message encoding, or 8b/10b encoding, to assure within-packet bit transitions, are also used to enhance clock synchronization and proper header location determination.
117 Citations
8 Claims
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1. A method of decoding a packet that does not include a preamble of known bit values, comprising:
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at a device configured to decode the packet;
despreading the packet using a spreading code,identifying a header of the packet that includes a sequence of bit transitions, identifying a body of the packet that includes information that has been transmitted by a transmitter, wherein identifying the header includes identifying a start of the packet based on the sequence of bit transitions, determining a first bit transition rate based on transitions in the header, identifying an end of packet sequence, determining a second bit transition rate based on transitions in the end of packet sequence, and estimating a bit transition rate for decoding bits in the body of the packet based on the first and second bit transition rates. - View Dependent Claims (2, 3, 4, 5)
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6. A receiver comprising:
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a receive buffer that is configured to receive a composite signal, a phase detector that is configured to detect a code-phase of a message that does not include a sequence of known bit values, a demodulator that is configured to; identify a header of the packet that includes a sequence of bit transitions, identify a start of the packet based on the sequence of bit transitions, identify a body of the packet that includes information that has been transmitted by a transmitter, determine a first bit transition rate based on the bit transitions in the header, identify an end of packet sequence, determine a second bit transition rate based on transitions in the end of packet sequence, and determine a bit transition rate for decoding bits in the body of the packet based on the first and second bit transition rates. - View Dependent Claims (7, 8)
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Specification