Method and apparatus for adaptively companding data packets in a data communication system

Claim 3

The method of claim 1, wherein each of the plurality of data packets includes a selection flag, and wherein step (b) further comprises the step of setting the selection flag of each selected data packet to indicate that a particular data packet has been selected.

Claim 4

The method of claim 2, wherein step (f) comprises the step of determining whether the selection flag of at least one of the received compressed data packets is set.

Claim 5

The method of claim 1, wherein step (b) comprises the steps of: b1) assigning each of the plurality of data packets a corresponding sequence number; and b2) selecting, in sequence, at least two of the plurality of data packets to produce the at least one selected data packet.

Claim 6

The method of claim 4, wherein each of the plurality of data packets further includes an error correction flag, and wherein step (b) further comprises the steps of: b3) assigning the error correction flag of the at least one selected data packet and each unselected data packet having a sequence number less than the corresponding sequence number of a first selected data packet of the at least one selected data packet to a first value to indicate a respective grouping of data packets; and b4) assigning the error correction flag of each unselected data packet having a sequence number larger than the corresponding sequence number of a last selected data packet of the at least one selected data packet to a second value to distinguish the respective grouping from subsequent unselected packets; the method further comprising the steps of: i) determining, by the second communication device, whether a value of the error correction flag of each received compressed data packet is identical to an expected value of the error correction flag; and j) when the received compressed data packets do not include the at least one selected data packet and the value of the error correction flag of a received compressed data packet is not identical to the expected value of the error correction flag, transmitting, by the second communication device, a second response packet to the first communication device, wherein the second response packet indicates that the at least one selected data packet was not received.

Claim 7

The method of claim 4, wherein step (g) further comprises the step of, when the received compressed data packets include a selected data packet having a sequence number lower than an expected sequence number, excluding any reference to the selected data packet having the sequence number lower than the expected sequence number in the response packet.

Claim 8

The method of claim 1, wherein step (c) comprises the steps of: c1) comparing a first string of data in each data packet of the first group to a database of data entries; and c2) when at least a portion of the first string of data is identical to a data entry in the database, replacing the at least a portion of the first string of data with a code associated with the data entry, the code comprising less bits than the at least a portion of the first string of data.

Claim 9

The method of claim 7, wherein step (h) comprises the steps h1) upon receipt of the response packet, creating at least one additional data entry in the database based on which selected data packets were received by the second communication device; h2) comparing a second string of data in each data packet of the second group to the database of data entries including the at least one additional data entry; and h3) when at least a portion of the second string of data is identical to a data entry in the database, replacing the at least a portion of the second string of data with a code associated with the data entry, said code comprising less bits than the at least a portion of the second string of data.

Claim 10

The method of claim 1, further comprising the step of: i) when the received compressed data packets do not include the at least one selected data packet, transmitting, by the second communication device, a second response packet to the first communication device, wherein the second response packet indicates that the at least one selected data packet was not received.

Claim 11

The method of claim 1, wherein step (h) comprises the steps of: h1) upon receipt of the response packet, selecting, by the first communication device, at least one data packet of the second group of the plurality of data packets to produce at least one supplemental selected data packet; and h2) performing the second compression of each data packet in the second group based on the response packet to produce the adaptively compressed data packets, wherein the second group includes the at least one supplemental selected data packet.

Claim 12

The method of claim 10, further comprising the steps of: i) transmitting, by the first communication device, the adaptively compressed data packets to the second communication device; j) receiving, by the second communication device, the adaptively compressed data packets to produce received adaptively compressed data packets; k) determining, by the second communication device, whether the received adaptively compressed data packets include the at least one supplemental selected data packet; l) when the received adaptively compressed data packets include the at least one supplemental selected data packet, transmitting, by the second communication device, a second response packet to the first communication device, the second response packet indicating which selected data packets of the at least one supplemental selected data packet were received by the second communication device; and m) upon receipt of the second response packet, performing, by the first communication device, a third compression of each data packet in a third group of the plurality of data packets based on the second response packet to produce supplemental adaptively compressed data packets.

Claim 13

The method of claim 11, further comprising the step of: n) repeating steps (h) through (m) until the plurality of data packets are transmitted.

Claim 16

The method of claim 13, wherein each of the plurality of data packets includes a selection flag, and wherein step (b) further comprises the step of setting the selection flag of each selected data packet to indicate that a particular data packet has been selected.

Claim 17

The method of claim 13, wherein step (b) comprises the steps of: b1) assigning each of the plurality of data packets a corresponding sequence number; and b2) selecting, in sequence, at least two of the plurality of data packets to produce the at least one selected data packet.

Claim 18

The method of claim 15, wherein each of the plurality of data packets further includes an error correction flag, and wherein step (b) further comprises the steps of: b3) assigning the error correction flag of the at least one selected data packet and each unselected data packet having a sequence number less than the corresponding sequence number of a first selected data packet of the at least one selected data packet to a first value to indicate a respective grouping of data packets; and b4) assigning the error correction flag of each unselected data packet having a sequence number larger than the corresponding sequence number of a last selected data packet of the at least one selected data packet to a second value to distinguish the respective grouping from subsequent unselected packets.

Claim 19

The method of claim 13, wherein step (c) comprises the steps of: c1) comparing a first string of data in each data packet of the first group to a database of data entries; and c2) when at least a portion of the first string of data is identical to a data entry in the database, replacing the at least a portion of the first suing of data with a code associated with the data entry, the code comprising less bits than the at least a portion of the first string of data.

Claim 20

The method of claim 17, wherein step (f) comprises the steps of: f1) creating at least one additional data entry in the database based on which selected data packets were received by the second communication device; f2) comparing a second string of data in each data packet of the second group to the database of data entries including the at least one additional data entry; and f3) when at least a portion of the second string of data is identical to a data entry in the database, replacing the at least a portion of the second string of data with a code associated with the data entry, said code comprising less bits than the at least a portion of the second string of data.

Claim 23

The method of claim 19, wherein each of the plurality of compressed data packets includes a selection flag and wherein step (b) comprises the step of determining whether the selection flag of at least one of the received compressed data packets is set.

Claim 24

The method of claim 19, wherein each of the plurality of compressed data packets further includes a sequence number and an error correction flag, the error correction flag of the at least one selected data packet being assigned a first value to indicate a respective grouping of selected data packets, and the error correction flag of each unselected data packet having a sequence number larger than a sequence number of a last selected data packet being assigned a second value to distinguish the respective grouping from subsequent unselected data packets, the method further comprising the steps of: f) determining whether a value of the error correction flag of each received compressed data packet is identical to an expected value of the error correction flag; and g) when the received compressed data packets do not include the at least one selected data packet and the value of the error correction flag of a received compressed data packet is not identical to the expected value of the error correction flag, transmitting a second response packet to the second communication device, wherein the second response packet indicates that the at least one selected packet was not received.

Claim 25

The method of claim 19, wherein each of the plurality of compressed data packets includes a sequence number and wherein step (c) further comprises the step of, when the received compressed data packets include a selected data packet having a sequence number lower than an expected sequence number, excluding any reference in the response packet to the selected data packet having the sequence number lower than the expected sequence number.

Claim 26

The method of claim 22, wherein the expected sequence number comprises a sequence number subsequent to a sequence number of a last unselected data packet received prior to receiving the plurality of compressed data packets.

Claim 27

The method of claim 22, wherein the expected sequence number comprises a sequence number subsequent to a sequence number of a last data packet received prior to receiving the plurality of compressed data packets.

Claim 28

The method of claim 19, wherein the step of transmitting the response packet to the second communication device comprises the step of transmitting a bitmap to the second communication device, the bitmap indicating which selected data packets of the at least one selected data packet were received.

Claim 29

A communication device for transmitting adaptively compressed data packets, the communication device comprising: a data packet generator; a selector, coupled to the data packet generator, for selecting at least one of a plurality of data packets produced by the data packet generator to produce at least one selected data packet, wherein a quantity of the at least one selected data packet is less than the plurality of data packets; a memory, coupled to the selector, for storing the at least one selected data packet; a database, coupled to the memory, containing data entries that associate particular data strings to corresponding compressed code words, each compressed code word containing fewer bits than a corresponding particular data string; a compressor, coupled to the selector and the database, for comparing portions of a group of the plurality of data packets, that includes the at least one selected data packet, to the data entries in the database and, when particular portions of the group match respective data entries, substituting corresponding compressed code words for those particular portions to produce compressed data packets; a transmitter, coupled to the compressor, for transmitting the compressed data packets to a target communication device; and a receiver, coupled to the database, for receiving a response packet from the target communication device, instructing the database to retrieve, from the memory, selected data packets of the at least one selected data packet identified in the response packet, and instructing the database to create additional data entries corresponding to the selected data packets, thereby allowing the database to be adaptively updated for subsequent compressed data packet transmissions.

Claim 30

A communication device for transmitting adaptively compressed data packets, the communication device comprising: a data packet generator; a selector, coupled to the data packet generator, for selecting at least one of a plurality of data packets produced by the data packet generator to produce at least one selected data packet, wherein a quantity of the at least one selected data packet is less than the plurality of data packets; a memory, coupled to the selector, for storing the at least one selected data packet; a database, coupled to the memory, containing data entries that associate particular data strings to corresponding compressed code words, each compressed code word containing fewer bits than a corresponding particular data string; a compressor, coupled to the selector and the database, for comparing portions of a group of the plurality of data packets, that includes the at least one selected data packet, to the data entries in the database and, when particular portions of the group match respective data entries, substituting corresponding compressed code words for those particular portions to produce compressed data packets; a transmitter, coupled to the compressor, for transmitting the compressed data packets to a target communication device; and a receiver, coupled to the database, for receiving a response packet from the target communication device, instructing the database to retrieve, from the memory, selected data packets of the at least one selected data packet identified in the response packet, and instructing the database to create additional data entries corresponding to the selected data packets, thereby allowing the database to be adaptively updated for subsequent compressed data packet transmissions.

Claim 31

A communication device for receiving adaptively compressed data packets, the communication device comprising: a receiver that receives a plurality of compressed data packets from a sending communication device to produce received compressed data packets, the plurality of compressed data packets including at least one data packet selected by the sending communication device prior to transmission to produce at least one selected data packet, wherein a quantity of the at least one selected data packet is less than the plurality of compressed data packets; a database containing data entries that associate compressed code words with corresponding expanded data strings, each of the expanded data strings including more bits than a corresponding compressed code word; a selected packet determiner, coupled to the receiver and the database, that determines which of the received compressed data packets comprise the at least one selected data packet and that instructs the database to create an additional data entry for each selected data packet, thereby adaptively updating the database for use during a subsequent reception of compressed data packets; and an expander, coupled to the receiver and the database, that compares portions of the received compressed data packets to the data entries in the database and, when particular portions of the received compressed data packets match respective data entries, that substitutes corresponding expanded data strings for those particular portions to reproduce original data packets from the received compressed data packets.

Claim 32

A communication device for receiving adaptively compressed data packets, the communication device comprising: a receiver that receives a plurality of compressed data packets from a sending communication device to produce received compressed data packets, the plurality of compressed data packets including at least one data packet selected by the sending communication device prior to transmission to produce at least one selected data packet, wherein a quantity of the at least one selected data packet is less than the plurality of compressed data packets; a database containing data entries that associate compressed code words with corresponding expanded data strings, each of the expanded data strings including more bits than a corresponding compressed code word; a selected packet determiner, coupled to the receiver and the database, that determines which of the received compressed data packets comprise the at least one selected data packet and that instructs the database to create an additional data entry for each selected data packet, thereby adaptively updating the database for use during a subsequent reception of compressed data packets; and an expander, coupled to the receiver and the database, that compares portions of the received compressed data packets to the data entries in the database and, when particular portions of the received compressed data packets match respective data entries, that substitutes corresponding expanded data strings for those particular portions to reproduce original data packets from the received compressed data packets.

Claim 33

The communication device of claim 27, further comprising: a response packet generator, coupled to the selected packet determiner, that produces a response packet indicating which selected data packets of the at least one selected data packet were received by the selected packet determiner; and a transmitter, coupled to the response packet generator, that transmits the response packet to the sending communication device, thereby allowing the sending communication device to adaptively compress data packets prior to transmission based on which selected data packets of the at least one selected data packet were received by the selected packet determiner.

Claim 34

The communication device of claim 28, wherein the response packet generator comprises a bitmap generator that creates a bitmap representing which selected data packets of the at least one selected data packet were received by the selected packet determiner.

Claim 35

The communication device of claim 27, further comprising: a memory, coupled to the expander and the database, that stores expanded representations of the received compressed data packets that comprise the at least one selected data packet and, upon request from the database, provides the expanded representations to the database to facilitate creation of additional data entries for the at least one selected data packet.