SIGNALING PARAMETERS CHANNEL PROCESSING

• US 20100150131A1
• Filed: 07/27/2009
• Published: 06/17/2010
• Est. Priority Date: 12/12/2008
• Status: Abandoned Application

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Krishnamoorthi, Raghuraman, Mukkavilli, Krishna Kiran, Ling, Fuyun, Mantravadi, Ashok, Chari, Murali Ramaswamy, van Veen, Durk L., Krishnamurthi, Rajeev
• Application Number:
  US12/509,820
• Publication Number:
  US 20100150131A1
• Time in Patent Office: Days
• US Class Current: 370/350
• CPC Class Codes: H04L 23/02 adapted for orthogonal signalling
• CPC Class Codes: H04L 25/0204 of multiple channels
• CPC Class Codes: H04L 25/0218 with detection of nulls
• CPC Class Codes: H04L 25/023 with extension to other symbols
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 27/2647 Arrangements specific to the receiver only equalisation H04L27/01
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals

Abstract

In a multicasts wireless telecommunication system providing an aggregation of one or more independent data components as a flow, wherein the OIS is located at the latch point of the beginning of the superframe, and the OIS programming is latched at the superframe boundary, the improvement of deriving signal parameter information from Signaling Parameter Channel (SPC) symbols transmitted in a Forward Link only (FLO) network by deriving a time domain channel estimate by assuming each of the combinations for the signal parameter field in the scrambler seed and picking the signal parameter combination that yields the most energy in the time domain above a threshold value.

Claims

1. A method to process TDM symbols carrying information about signaling parameters used for generating the waveform in a wireless broadcast network.

2. The method of claim 1 where the wireless broadcast network is Forward Link Only (FLO) network.

3. The method of claim 1 where the signaling parameters are specific to an OFDM system such as FFT size, cyclic prefix length and pilot stagger pattern.

4. The method of claim 1 where the TDM symbols refer to the symbols comprising the Signaling Parameter Channel (SPC) in a Forward Link Only (FLO) network.

5. The method of claim 1 where processing the TDM symbols involves deriving signal parameter information from Signaling Parameter Channel (SPC) symbols transmitted in a Forward Link only (FLO) network by deriving a time domain channel estimate by assuming each of the combinations for the signal parameter field in the scrambler seed and picking the signal parameter combination that yields the most energy in the time domain above a threshold value.

6. The process of claim 5, wherein the time domain channel estimate is obtained by:

a. collecting one or more periods of the SPC samples in the domain;

b. performing an FFT on the collected time domain samples in a) to obtain the corresponding frequency domain pilot samples;

c. selecting one of several possibilities for the signal parameter information in the scrambler seed and descrambling the frequency domain pilot samples obtained in b);

d. performing extrapolation in the frequency domain to extend the pilot observations so that the total number of observations is a power of 512;

e. performing a 512 point IFFT operation on the extrapolated frequency domain samples obtained in d) to get a time domain channel estimate corresponding to the selected scrambler seed;

f. selecting an energy threshold and computing the sum of the energy of all the time domain channel taps that exceed the threshold;

g. repeating steps c) through f) with all possible combinations of the signal parameter field in the scrambler seed; and

h. determining the signal parameter combination that results in the maximum energy in g) as the transmitted signal parameter information.

7. The process of claim 5, wherein the time domain samples corresponding to the SPC symbols are identified in the superframe by selecting a factory default combination of the FFT, CP and pilot pattern for synchronizing with the superframe.

8. The process of claim 6, wherein all the steps are repeated for interlaces 0 and 4 in both the SPC symbols.

9. The process of claim 6, wherein the energy threshold in steps f) is precomputed.

10. The process of claim 6, wherein the energy threshold in steps f) is based on the maximum energy tap derived in step e).

11. The process of claim 6, wherein the time domain channel estimate in e) is obtained as a least squares estimate from the frequency domain pilot observations in c).

12. The process of claim 6, wherein the extrapolation in d) is performed using zero extrapolation, zero order hold or a filtering operation on all the pilot observations.

13. In a multicasts wireless telecommunication apparatus providing an aggregate of one or more independent data components as a flow, wherein the OIS is located at the latch point of the beginning of the superframe, and the OIS programming is latched at the superframe boundary, the apparatus improvement of:

means for deriving signal parameter information from Signaling Parameter Channel (SPC) symbols transmitted in a Forward Links only (FLO) network, comprising means for deriving a time domain channel estimate that selects each of the combinations for the signal parameter field in the scrambler seed; and

means for picking the signal parameter combination that yields the most energy in the time domain above a threshold value.

14. The multicast wireless telecommunication apparatus of claim 13, comprising:

a) means for collecting one or more periods of the SPC samples in the time domain;

b) means for performing an FFT on the collected time domain samples in a) to obtain the corresponding frequency domain pilot samples;

c) means for selecting one of several possibilities for the signal parameter information in the scrambler seed for descrambling the frequency domain pilot samples obtained in b);

d) means for performing extrapolation in the frequency domain to extend the pilot observation'"'"'s so that the total number of observations is a power of 512;

e) means for performing a 512 point IFFT operation on the extrapolated frequency domain samples obtained in d) to get a time domain channel estimate corresponding to the selected scramble seed; and

f) means for selecting an energy threshold and computing the sum of the energy of all the time domain channel taps that exceed the threshold.

15. The multicast telecommunication apparatus of claim 13 further comprising means for selecting a factory default combination of the FFT, CP and pilot pattern for synchronizing with the superframe to provide the time domain samples corresponding to the SPC symbols identified in the superframe.

16. The multicast telecommunication apparatus of claim 14 further comprising means to repeat all of the steps for interlaces 0 and 4 in both the SPC symbols.

17. The multicast telecommunication apparatus of claim 14, further comprising means to precompute the energy threshold in step f).

18. The multicast telecommunication apparatus of claim 14, further comprising means to precompute the energy threshold in step f) based on the maximum energy tap derived in step e).

19. The multicast telecommunication apparatus of claim 14, further comprising means to obtain the time domain channel estimate in e) as a least squares estimate from the frequency domain pilot observations in step c).

20. The multicast telecommunication apparatus of claim 14, further comprising means to perform the extrapolation in d) using zero extrapolation or zero order hold or a filtering operation on all of apparatus the pilot observations.

21. A computer-readable medium comprising instructions which, when executed by the machine, cause the machine to perform operations including:

deriving signal parameter information from Signaling Parameter Channel (SPC) symbols transmitted in a Forward Link only (FLO) network by deriving a time domain channel estimate by assuming each of the combinations for the signal parameter field in the scrambler seed and picking the signal parameter combination that yields the most energy in the time domain above a threshold value.

22. A computer-readable medium comprising instructions which, when executed by the machine, cause the machine to perform operations including:

a) collecting one or more periods of the SPC samples in the domain;

b) performing an FFT on the collected time domain samples in a) to obtain the corresponding frequency domain pilot samples;

c) selecting one of several possibilities for the signal parameter information in the scrambler seed and descrambling the frequency domain pilot samples obtained in b);

d) performing extrapolation in the frequency domain to extend the pilot observations so that the total number of observations is a power of 512;

e) performing a 512 point IFFT operation on the extrapolated frequency domain samples obtained in d) to get a time domain channel estimate corresponding to the selected scrambler seed;

f) selecting an energy threshold and computing the sum of the energy of all the time domain channel taps that exceed the threshold;

g) repeating steps c) through f) with all possible combinations of the signal parameter field in the scrambler seed; and

h) determining the signal parameter combination that results in the maximum energy in g) as the transmitted signal parameter information.