Method of transmitting voice coding information using cyclic redundancy check bits

• US 5,754,734 A
• Filed: 10/31/1995
• Issued: 05/19/1998
• Est. Priority Date: 10/31/1995
• Status: Expired due to Term

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Emeott, Stephen Paul, White, Gregory Charles, Lee, Bob Hsun, Ronk, John G.
• Primary Examiner(s): MacDonald, Allen R.
• Assistant Examiner(s): COLLINS, ALPHONSO
• Application Number:
  US08/550,972
• Time in Patent Office: 931 Days
• Field of Search: 395/2.2, 395/2.33, 395/2.35, 395/2.36, 395/2.37, 395/2.38
• US Class Current: 704/226
• CPC Class Codes: G10L 19/005 Correction of errors induced by the transmission channel, if related to the coding algorithm
• CPC Class Codes: H04L 1/0071 Use of interleaving interleaving per se H03M13/27
• CPC Class Codes: H04L 1/0083 Formatting with frames or packets; Protocol or part of protocol for error control
• CPC Class Codes: H04L 2001/0098 Unequal error protection

Abstract

A method of transmitting voice coding information is provided. First and second frames of voice coding information are provided. Each frame is then prioritized based on which bits need to be forward-error corrected, thus forming first and second prioritized frames. A six-bit CRC value is then computed based on the prioritized first and second frames. The six-bit CRC value is then split into first and second 3-bit CRC units. The first CRC unit is then combined with the first prioritized frame to form a modified first frame, and the second CRC unit is then combined with the second prioritized frame to form a modified second frame. The modified first and second frames are each then error correction coded to form first and second sets of symbols, respectively. The first and second set of symbols are then interleaved into a transmission unit, which is then transmitted.

Claims

1. A method of transmitting voice coding information, comprising the steps of:

(a) providing a first frame of voice coding information comprising a plurality of bits and providing a second frame of voice coding information comprising a plurality of bits;

(b) prioritizing the bits of the first frame to form a first prioritized frame of voice coding information;

(c) prioritizing the bits of the second frame to form a second prioritized frame of voice coding information;

(d) forming a set of bits, the set of bits comprising a first part of the first prioritized frame and a second part of the second prioritized frame;

(e) computing a single cyclical redundancy check ("CRC") value using the set of bits;

(f) parsing the single CRC value into a first CRC unit and a second CRC unit;

(g) combining the first CRC unit with the first prioritized frame to form a modified first frame;

(h) combining the second CRC unit with the second prioritized frame to form a modified second frame;

(i) error correction coding at least some of the bits of the modified first frame to provide a first set of symbols;

(j) error correction coding at least some of the bits of the modified second frame to provide a second set of symbols;

(k) interleaving the first set of symbols and the second set of symbols to provide a transmission unit; and

,

(l) transmitting the transmission unit.

2. The method of claim 1 where the first frame comprises 180 bits.

3. The method of claim 1 where the second frame comprises 180 bits.

4. The method of claim 1 where the step of prioritizing the bits of the first frame to form a first prioritized frame of voice coding information comprises identifying bits from the first frame that are to be forward error correction coded, thus forming a first group of bits.

5. The method of claim 1 where the step of prioritizing the bits of the second frame to form a second prioritized frame of voice coding information comprises identifying bits from the second frame that are to be forward error correction coded, thus forming a second group of bits.

6. The method of claim 4 where the first group comprises 90 bits.

7. The method of claim 5 where the second group comprises 90 bits.

8. The method of claim 1 where the set of bits comprises 70 bits.

9. The method of claim 6 where the first part comprises 35 bits, the first part being based on the first group.

10. The method of claim 7 where the second part comprises 35 bits, the second part being based on the second group.

11. The method of claim 1 where the single cyclical redundancy check value comprises 6 bits.

12. The method of claim 1 where the first CRC unit comprises 3 bits.

13. The method of claim 1 where the second CRC unit comprises 3 bits.

14. The method of claim 1 where the first set of symbols comprises 83 symbols.

15. The method of claim 1 where the second set of symbols comprises 83 symbols.

16. The method of claim 1 where the transmission unit comprises 166 symbols.

17. The method of claim 1 where the modified first frame comprises 183 bits.

18. The method of claim 1 where the modified second frame comprises 183 bits.