Enhanced compression formats for data compression

Patent metadata

Field	Value
Publication number	US-2016309364-A1
Application number	US-201615095374-A
Country	US
Kind code	A1
Filing date	Apr 11, 2016
Priority date	Apr 20, 2015
Publication date	Oct 20, 2016
Grant date	—

Abstract

Certain aspects of the present disclosure generally relate to wireless communications and, more particularly, to enhanced compression formats for data compression (e.g., uplink data compression (UDC)). A method is provided for wireless communications. The method generally includes determining one or more blocks of data in a current packet matching one or more blocks of data in one or more portions of one or more previous packets stored in a memory, compressing at least a portion of the current packet based on an enhanced compression format having reduced metadata relative to another compression format to indicate one or more of the matching blocks of data, and transmitting the compressed current packet. Numerous other aspects are provided.

First claim

What is claimed is:

1 . A method for wireless communications, comprising:
determining one or more blocks of data in a current packet matching one or more blocks of data in one or more portions of one or more previous packets stored in a memory; compressing at least a portion of the current packet based on an enhanced compression format having reduced metadata relative to another compression format to indicate one or more of the matching blocks of data; and transmitting the compressed current packet.

2 . The method of claim 1 , wherein the enhanced compression format comprises enhanced uplink data compression (UDC).

3 . The method of claim 1 , further comprising:
compressing another portion of the current packet based on the other compression format to indicate other matching blocks of data.

4 . The method of claim 1 , wherein compressing the at least a portion of the current packet based on the enhanced compression format comprises:
including a pointer to a memory location of a stored compression header of a previous packet that fully matches or partially matches a compression header of the current packet.

5 . The method of claim 4 , wherein the previous packet is a packet immediately preceding the current packet.

6 . The method of claim 4 , wherein:
the stored compression header of the previous packet fully matches the compression header of the current packet, and compressing the at least a portion of the current packet based on the enhanced compression format comprises indicating in a packet action field in the current packet to reuse the stored compression header of the previous packet.

7 . The method of claim 6 , wherein the current packet does not include a compression header.

8 . The method of claim 4 , wherein the stored compression header comprises a short compression header having reduced metadata relative to a compression header of the other compression format.

9 . The method of claim 4 , further comprising:
storing compression headers of a plurality of previously transmitted packets in the memory; assigning template IDs to the stored compression headers; wherein compressing the current packet based on the enhanced compression format comprises indicating the template IDs of the stored compression headers in the current packet.

10 . The method of claim 1 , wherein compressing the at least a portion of the current packet based on the enhanced compression format comprises:
including, in the current packet, a short compression header having reduced metadata relative to a compression header of the other compression format.

11 . The method of claim 1 , wherein the short compression header includes a checksum value equal to a sum of the min(first Match length, 5) bytes.

12 . The method of claim 10 , wherein the short compression header includes a static portion that indicates, for one or more the matching blocks of data, a lookback location in a memory common to each of the matching blocks of data, a Number of bytes to copy from the lookback location and a number of mismatched data in the copied block, and a dynamic portion that indicates a size of a block of matching and mismatching data.

13 . The method of claim 10 , further comprising:
assigning template IDs to the one or more previous packets stored in the memory, wherein compressing the current packet based on the enhanced compression format comprises indicating the template ID of one of the one or more previous packets in the short compression header of the current packet.

14 . The method of claim 1 , further comprising:
indexing metadata of one or more previously transmitted compression packets, wherein compressing the current packet based on the enhanced compression format comprises: indicating, in the current packet, a number of the matching metadata, and for each match, a starting index of the matching metadata and a number indices, corresponding to that matching metadata.

15 . The method of claim 1 , further comprising:
indexing metadata of one or more previously transmitted compression packets, metadata at the beginning of the current packet matches stored metadata, and wherein compressing the current packet based on the enhanced compression format comprises: indicating, in the current packet, a number of the matching metadata.

16 . The method of claim 14 , wherein the previously transmitted compression packet comprises the immediately preceding compression packet.

17 . The method of claim 14 , wherein the metadata comprises at least one of metadata related to at least one of a compression header of the other compression format or a short compression header having reduced metadata relative to the compression header of the other compression format.

18 . The method of claim 17 , wherein indexing the metadata comprises:
only indexing metadata related to a dynamic portion of compression headers of the other format; and indexing metadata related to both a dynamic portion and a static portion of compression header of the enhanced compression format.

19 . The method of claim 17 , wherein indexing the metadata comprises:
tagging the metadata based on whether the metadata relates to a compression header of the other compression format or a short compression header.

20 . The method of claim 17 , wherein indexing the metadata comprises:
indexing the metadata related to a compression header of the other compression format in a first index; and indexing the metadata related to a short compression header in a second index.

21 . The method of claim 1 , further comprising:
each time a new packet is stored in the memory, updating at least one of a lookback location or an absolute pointer associated with each of the one or more previous packets stored in the memory.

22 . The method of claim 1 , wherein compressing the current packet based on the enhanced compression format comprises:
including a lookback offset in the current packet used to update the lookback location associated with metadata stored in memory, wherein a value of the lookback offset is updated each time a new packet is stored in the memory.

23 . The method of claim 1 , wherein compressing the current packet based on the enhanced compression format comprises at least one of:
including an indication in the current packet that the current packet should be stored in the memory, including an indication in the current packet that the metadata associated with the current packet should be stored in the memory, or including an indication in the current packet of a flow for which the packet and the metadata associated with the current packet should be stored in the memory.

24 . The method of claim 1 , wherein the compressed current packet includes at least one extension bit that indicates the enhanced compression format used to compress the at least a portion of the current packet.

25 . The method of claim 1 , wherein the compressed current packet includes an indication of mismatched bytes after all compression headers according to an ordering of the compression headers associated with the mismatched bytes.

26 . The method of claim 1 , wherein the compressed current packet includes an indication of mismatched bytes associated with a compression header immediately after the compression header.

27 . An apparatus for wireless communications, comprising:
means for determining one

Assignees

• Qualcomm Inc

Inventors

• Maheshwari Shailesh
• Zacharias Leena
• Gholmieh Aziz
• Balasubramanian Srinivasan
• Dalmiya Vishal
• Raina Ashwini
• Kapoor Rohit

Classifications

• H04L69/04 Primary

  Protocols for data compression, e.g. ROHC · CPC title

• H04W28/06 Primary

  Optimizing {the usage of the radio link}, e.g. header compression, information sizing {, discarding information (system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365)} · CPC title

• H03M7/30

  Compression (speech analysis-synthesis for redundancy reduction G10L19/00; for image communication H04N); Expansion; Suppression of unnecessary data, e.g. redundancy reduction · CPC title

• H03M7/4018

  Context adapative binary arithmetic codes [CABAC] · CPC title

• H04W72/0413

  Electricity · mapped topic