Apparatus and method for determining and representing a synchronization status

• US 8,718,125 B2
• Filed: 12/11/2007
• Issued: 05/06/2014
• Est. Priority Date: 01/10/2007
• Status: Active Grant

• Current Assignee: Rohde & Schwarz GmbH & Company KG
• Original Assignee: Rohde & Schwarz GmbH & Company KG
• Inventors: Steffens, Johannes, Feldhaus, Gregor, Fischer, Volker, Roth, Matthias
• Primary Examiner(s): Fan, Chieh M
• Assistant Examiner(s): Stevens, Brian J
• Application Number:
  US12/521,512
• Publication Number:
  US 20100316106A1
• Time in Patent Office: 2,338 Days
• Field of Search: 375/228, 375/224, 455/67.11
• US Class Current: 375/228
• CPC Class Codes: H04L 27/2656 Frame synchronisation, e.g. packet synchronisation, time division duplex [TDD] switching point detection or subframe synchronisation
• CPC Class Codes: H04L 27/2662 Symbol synchronisation

Abstract

A device and method for determining and displaying on a display element the status of at least one synchronization implemented in an electronic measuring instrument or a telecommunications device is provided. The device includes several functional units provided within the electronic measuring instrument or the telecommunications device, and each functional unit determines at least one parameter, the value of which corresponds to the status of the synchronization implemented in the respective functional unit.

Claims

1. A device for the determination and display of synchronization statuses of a receiver-end communications path in an electronic measuring instrument or telecommunications device, comprising:

a plurality of synchronization stages; and

a display element,

wherein a received signal is subjected to the plurality of synchronization stages in a defined time sequence and the electronic measuring instrument or telecommunications device comprises a corresponding synchronization unit for each synchronization stage to be implemented,

wherein each synchronization unit is adapted for determining at least one parameter, the at least one parameter indicating the synchronization status of the corresponding synchronization unit, the indicated synchronization status is one of a plurality of possible synchronization statuses, and the plurality of possible synchronization statuses comprises a successful synchronization status and an unsuccessful synchronization status,

wherein the device is adapted for displaying on the display element, based on the parameters, the synchronization statuses of the synchronization units along the receiver-end communication path,

wherein the display element displays a plurality of blocks and each block on the display element represents a synchronization unit of the measuring instrument or telecommunications device, and

wherein one block on the display element represents an FFT (Fast Fourier Transformation) or an IFFT (inverse Fast Fourier Transformation).

2. The device according to claim 1, wherein the device is adapted to the electronic measuring instrument or telecommunication device comprising an OFDM (Orthogonal Frequency-Division Multiplexing) receiver.

3. The device according to claim 1, wherein the synchronization units are disposed in different branches within the measuring instrument or telecommunications device and fulfill different tasks.

4. The device according to claim 3, wherein the different tasks are implemented in the defined time sequence.

5. The device according to claim 1, wherein a serial arrangement of several blocks on the display element corresponds to the defined time sequence.

6. The device according to claim 1, wherein the plurality of blocks on the display element are connected by arrows.

7. The device according to claim 6, wherein the arrows, which connect the plurality of blocks, adopt a first color status, a second color status or a third color status.

8. The device according to claim 7, wherein the first color status of an arrow represents a successful succession of synchronizations implemented by the synchronization units of the preceding blocks.

9. The device according to claim 8, wherein the second color status of an arrow represents a synchronization unsuccessfully implemented by the synchronization units of the preceding blocks.

10. The device according to claim 1, wherein the plurality of blocks on the display element adopt a first color status or a second color status dependent upon the respective status of each block.

11. The device according to claim 10, wherein the first color status of a block displays a result of a successfully-implemented synchronization corresponding to the block.

12. The device according to claim 11, wherein the second color status of a block displays a result of an unsuccessfully-implemented synchronization corresponding to the block.

13. The device according to claim 1, wherein a bar diagram with a scale is provided within each of the blocks.

14. The device according to claim 13, wherein the scale provides at least two value fields.

15. The device according to claim 14,

wherein three value fields represent three different confidence-value ranges, and

wherein a confidence value indicates a probability for the occurrence of a status of the synchronization of the associated synchronization unit.

16. The device according to claim 1, wherein, through a selection of a block and a subsequent activation of the selected block on the display element, a detailed item of information regarding the determined status with reference to the synchronization implemented by the synchronization unit, which corresponds to the selected block, is reproduced.

17. The device according to claim 16, wherein the activation of the selected block on the display element is implemented via a mouse, a previously-programmed key-stroke combination, or a remote control command implemented via a GPIB (General Purpose Interface Bus) interface or via a LAN (Local Area Network) interface.

18. A method for the determination and display of synchronization statuses of a receiver-end communications path in an electronic measuring instrument or telecommunications device comprising:

subjecting a received signal to a plurality of synchronization stages in a defined time sequence, wherein the electronic measuring instrument or telecommunications device comprises a corresponding synchronization unit for each synchronization stage to be implemented,

adapting each synchronization unit for determining at least one parameter, wherein the parameter indicates the synchronization status of the corresponding synchronization unit, the indicated synchronization status is one of a plurality of possible synchronization statuses, and the plurality of possible synchronization statuses comprises a successful synchronization status and an unsuccessful synchronization status, and

displaying on the display element, based on the parameters, the synchronization statuses of the synchronization units along the receiver-end communication path

wherein the received signal is content read out from a reception buffer of an OFDM (Orthogonal Frequency-Division Multiplexing) receiver,

wherein the content of the reception buffer is subjected to a signal identification, the result of which is an identified signal sequence,

wherein the identified signal sequence is subjected to a cyclic prefix synchronization with regard to a cyclically-repeated signal portion, especially a guard interval, and

wherein a useful portion of the identified signal sequence is disposed between two such signal portions.

19. The method according to claim 18, wherein the useful portion of the identified signal sequence is extracted from the cyclic prefix synchronization.

20. The method according to claim 18, wherein the useful portion of the identified signal sequence is subjected to a Fast Fourier Transformation (FFT), from which a Fourier-transformed signal is obtained.

21. The method according to claim 20, wherein the Fourier-transformed signal is subjected to a frame synchronization, from which a frame-synchronous Fourier-transformed signal is obtained.

22. The method according to claim 21,

wherein a channel estimation is implemented using the frame-synchronous Fourier-transformed signal, and

wherein every noise-laden pilot symbol transmitted within a now-known frame is compared with a pilot symbol, which is present at the receiver end without transmission error.

23. The method according to claim 22, wherein a transmission function for a radio channel is estimated from a result of a comparison of two pilots symbols.

24. The method according to claim 23, wherein the frame-synchronous Fourier-transformed signal, equalized by means of the estimated transmission function, is demodulated with a demodulation method specified in the receiver.

25. The method according to claim 24, wherein a transmitted signal or transmitted data symbol is roughly estimated on a basis of a previously-defined threshold value.

26. The method according to claim 25, wherein the roughly-estimated data symbol is subjected to a refined estimation process.

27. The method according to claim 26, wherein, through implementation of the rough and the refined estimation method, in each case, a recovered data symbol is further processed.

28. The method according to claim 27, wherein every recovered data symbol is displayed after an analysis on the display element.