Granted Patent B2

US 7,907,637 · App. 12/062,734 · Granted Mar 15, 2011

Abstract

Claims (94)

1. A method of acquisition in a mobile multimedia multicast system, said method comprising:

receiving a superframe comprising a first digital symbol in a receiver operating in a first state of operation;

assuming the first received digital symbol to be a Time Division Multiplexed (TDM) pilot symbol;

calculating a first sparseness index of said first symbol;

storing said first sparseness index;

operating said receiver in a second state of operation;

receiving a second digital symbol;

calculating a second sparseness index for said second digital symbol;

said receiver remaining in said second state of operation when said second sparseness index is greater than said first sparseness index, wherein said second digital symbol is assumed to be said TDM pilot symbol;

verifying that the last assumed TDM pilot symbol is the correct TDM pilot of said superframe,

wherein when said second sparseness index is less than said first sparseness index, then said method further comprising:

said receiver assuming said second digital symbol is a Wide-area Identification Channel (WIC) symbol; and

said receiver switching to a third state of operation;

receiving additional new digital symbols;

comparing a sparseness index of each said additional digital symbols with said first sparseness index; and

said receiver switching to said second state of operation whenever a sparseness index of a newly received digital symbol is greater than said first sparseness index,

wherein when the sparseness index of said newly received digital symbol is less than said first sparseness index, then said method further comprising:

said receiver switching to a fourth state of operation;

said receiver switching to a fifth state of operation upon completion of said fourth state of operation;

said receiver switching to a sixth state of operation upon completion of said fifth state of operation;

said receiver switching to a seventh state of operation upon completion of said sixth state of operation; and

said receiver remaining in said seventh state of operation as long as each newly arriving digital symbol has a smaller sparseness index than said first sparseness index.

2. The method of claim 1 , further comprising said receiver switching to an eighth state of operation when said receiver resides in said seventh state of operation for five consecutive received digital symbols.

3. The method of claim 2 , further comprising:

comparing a sparseness index of said newly received digital symbol with said first sparseness index; and

when a sparseness index of said newly received digital signal is less than said first sparseness index, said method further comprising:

performing a turbo-decoding process on Overhead Information symbols (OIS) of said superframe; and

checking erasure fields of said superframe for errors.

4. The method of claim 3 , wherein when said erasure fields are correct, said method further comprising said receiver switching to a ninth state of operation which signifies an end of an acquisition phase, and wherein the last assumed TDM pilot symbol is determined to be the correct TDM pilot symbol.

5. The method of claim 3 , wherein when said erasure fields are non-zero, then said method further comprising:

said receiver switching to said first state of operation; and

said method repeating.

6. A non-transitory program storage device readable by computer, and comprising a program of instructions executable by said computer to perform a method of acquisition in a mobile multimedia multicast system, said method comprising:

receiving a superframe comprising a first digital symbol in a receiver operating in a first state of operation;

assuming the first received digital symbol to be a Time Division Multiplexed (TDM) pilot symbol;

calculating a first sparseness index of said first symbol;

storing said first sparseness index;

operating said receiver in a second state of operation;

receiving a second digital symbol;

calculating a second sparseness index for said second digital symbol;

said receiver remaining in said second state of operation when said second sparseness index is greater than said first sparseness index, wherein said second digital symbol is assumed to be said TDM pilot symbol;

verifying that the last assumed TDM pilot symbol is the correct TDM pilot of said superframe,

wherein when said second sparseness index is less than said first sparseness index, then said method further comprising:

said receiver assuming said second digital symbol is a Wide-area Identification Channel (WIC) symbol; and

said receiver switching to a third state of operation;

receiving additional new digital symbols;

comparing a sparseness index of each said additional digital symbols with said first sparseness index; and

said receiver switching to said second state of operation whenever a sparseness index of a newly received digital symbol is greater than said first sparseness index,

wherein when the sparseness index of said newly received digital symbol is less than said first sparseness index, then said method further comprising:

said receiver switching to a fourth state of operation;

said receiver switching to a fifth state of operation upon completion of said fourth state of operation;

said receiver switching to a sixth state of operation upon completion of said fifth state of operation;

said receiver switching to a seventh state of operation upon completion of said sixth state of operation; and

said receiver remaining in said seventh state of operation as long as each newly arriving digital symbol has a smaller sparseness index than said first sparseness index.

7. The program storage device of claim 6 , wherein said method further comprising said receiving switching to an eighth state of operation when said receiver resides in said seventh state of operation for five consecutive received digital symbols.

8. The program storage device of claim 7 , wherein said method further comprising:

comparing a sparseness index of said newly received digital symbol with said first sparseness index; and

when a sparseness index of said newly received digital signal is less than said first sparseness index, said method further comprising:

performing a turbo-decoding process on Overhead Information symbols (OIS) of said superframe; and

checking erasure fields of said superframe for errors.

9. The program storage device of claim 8 , wherein when said erasure fields are correct, said method further comprising said receiver switching to a ninth state of operation which signifies an end of an acquisition phase, and wherein the last assumed TDM pilot symbol is determined to be the correct TDM pilot symbol.

10. The program storage device of claim 8 , wherein when said erasure fields are non-zero, then said method further comprising:

said receiver switching to said first state of operation; and

said method repeating.

11. A receiver comprising a processor configured to:

receive a superframe comprising a first digital symbol in said receiver operating in a first state of operation;

assume the first received digital symbol to be a Time Division Multiplexed (TDM) pilot symbol;

calculate a first sparseness index of said first symbol;

store said first sparseness index;

operate said receiver in a second state of operation;

receive a second digital symbol;

calculate a second sparseness index for said second digital symbol, wherein said receiver remains in said second state of operation when said second sparseness index is greater than said first sparseness index, wherein said second digital symbol is assumed to be said TDM pilot symbol;

verify that the last assumed TDM pilot symbol is the correct TDM pilot of said superframe,

wherein when said second sparseness index is less than said first sparseness index, then said processor is further configured to:

assume said second digital symbol is a Wide-area Identification Channel (WIC) symbol; and

switch to a third state of operation;

receive additional new digital symbols;

compare a sparseness index of each said additional digital symbols with said first sparseness index; and

switch to said second state of operation whenever a sparseness index of a newly received digital symbol is greater than said first sparseness index,

wherein when the sparseness index of said newly received digital symbol is less than said first sparseness index, then said processor is further configured to:

switch to a fourth state of operation;

switch to a fifth state of operation upon completion of said fourth state of operation;

switch to a sixth state of operation upon completion of said fifth state of operation;

switch to a seventh state of operation upon completion of said sixth state of operation; and

remain in said seventh state of operation as long as each newly arriving digital symbol has a smaller sparseness index than said first sparseness index.

12. The receiver of claim 11 , wherein said receiver performs acquisition in a mobile multimedia multicast system.

13. The receiver of claim 11 , wherein said processor is further configured to switch to an eighth state of operation when said receiver resides in said seventh state of operation for five consecutive received digital symbols.

14. The receiver of claim 13 , wherein said processor is further configured to:

compare a sparseness index of said newly received digital symbol with said first sparseness index; and

when a sparseness index of said newly received digital signal is less than said first sparseness index, said processor is further configured to:

perform a turbo-decoding process on Overhead Information symbols (OIS) of said superframe; and

check erasure fields of said superframe for errors.

15. The receiver of claim 14 , wherein when said erasure fields are correct, said processor is further configured to switch to a ninth state of operation which signifies an end of an acquisition phase, and wherein the last assumed TDM pilot symbol is determined to be the correct TDM pilot symbol.

16. The receiver of claim 14 , wherein when said erasure fields are non-zero, then said processor is further configured to switch to said first state of operation.

Assignments (23)