CN107454029B - Method and apparatus for pseudo-random noise phase detection - Google Patents

Method and apparatus for pseudo-random noise phase detection Download PDF

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CN107454029B
CN107454029B CN201610371314.1A CN201610371314A CN107454029B CN 107454029 B CN107454029 B CN 107454029B CN 201610371314 A CN201610371314 A CN 201610371314A CN 107454029 B CN107454029 B CN 107454029B
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CN107454029A (en
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米哈伊尔·沃利安斯奇
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Rohde and Schwarz GmbH and Co KG
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/26—Systems using multi-frequency codes
    • H04L27/2601—Multicarrier modulation systems
    • H04L27/2647—Arrangements specific to the receiver only
    • H04L27/2655—Synchronisation arrangements
    • H04L27/2656—Frame synchronisation, e.g. packet synchronisation, time division duplex [TDD] switching point detection or subframe synchronisation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/32—Carrier systems characterised by combinations of two or more of the types covered by groups H04L27/02, H04L27/10, H04L27/18 or H04L27/26
    • H04L27/34—Amplitude- and phase-modulated carrier systems, e.g. quadrature-amplitude modulated carrier systems
    • H04L27/38—Demodulator circuits; Receiver circuits
    • H04L27/3845—Demodulator circuits; Receiver circuits using non - coherent demodulation, i.e. not using a phase synchronous carrier
    • H04L27/3854—Demodulator circuits; Receiver circuits using non - coherent demodulation, i.e. not using a phase synchronous carrier using a non - coherent carrier, including systems with baseband correction for phase or frequency offset
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L65/00—Network arrangements, protocols or services for supporting real-time applications in data packet communication
    • H04L65/60—Network streaming of media packets
    • H04L65/61—Network streaming of media packets for supporting one-way streaming services, e.g. Internet radio
    • H04L65/611—Network streaming of media packets for supporting one-way streaming services, e.g. Internet radio for multicast or broadcast
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/69—Spread spectrum techniques
    • H04B1/707—Spread spectrum techniques using direct sequence modulation
    • H04B1/7073—Synchronisation aspects
    • H04B1/7075—Synchronisation aspects with code phase acquisition
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/0014—Carrier regulation
    • H04L2027/0044—Control loops for carrier regulation
    • H04L2027/0063—Elements of loops
    • H04L2027/0067—Phase error detectors
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/0014—Carrier regulation
    • H04L2027/0083—Signalling arrangements
    • H04L2027/0089—In-band signals
    • H04L2027/0093—Intermittant signals
    • H04L2027/0095—Intermittant signals in a preamble or similar structure

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  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Noise Elimination (AREA)
  • Synchronisation In Digital Transmission Systems (AREA)

Abstract

The present invention relates to a method and apparatus for pseudo-random noise phase detection. The received signal includes a plurality of signal frames. Each signal frame has a frame header and a frame body. The frame header has a pseudo-random noise sequence of symbols. A first segment of symbols of a first pseudorandom noise sequence of the first signal frame is extracted. A second segment of the symbol of the second pseudorandom noise sequence of the second frame is extracted. The first and second pseudo-random noise sequences belong to directly consecutive signal frames. A phase difference between the first and second pseudorandom noise sequences is determined based on the cyclic cross correlation of the first and second segments. The number of frames of the signal frame is determined based on the phase difference.

Description

Method and apparatus for pseudo-random noise phase detection
Technical Field
The present invention relates to a method and apparatus for pseudo-random noise (PN) phase detection of a received Digital Terrestrial Multimedia Broadcasting (DTMB) signal.
Background
Digital Terrestrial Multimedia Broadcasting (DTMB) is a standard for digital terrestrial television used, for example, in hong kong, china and australia, china. Digital terrestrial multimedia broadcasting uses signal frames within superframes. Each signal frame includes a frame header and a frame body. The frame header includes a pseudo-random noise (PN) sequence. The pseudo-random noise sequence is used for estimating frequency offset and sampling frequency offset as well as for channel estimation and removal of inter-symbol interference. The phase of the pseudo-random noise sequence is critical to the synchronization of the digital terrestrial multimedia broadcast receiver. Since the exact phase of the pseudo random noise sequence of the signal frame is not known in advance, it is important that it is determined before the pseudo random noise sequence can be further evaluated.
Code acquisition is typically performed based on correlation of a received signal with a locally generated pseudorandom noise sequence. A disadvantage of this approach is poor performance in channels that suffer from multipath fading, such as single frequency networks. Slightly different methods and systems for pseudo random noise sequence phase detection for digital terrestrial multimedia broadcast receivers are also known, for example, from US 9,166,776B 2 and US 8,693,606. However, all of these known methods and systems are not efficient enough in terms of the speed and complexity of the algorithms applied.
Disclosure of Invention
The present invention provides a method for pseudo-random noise (PN) phase detection of a received Digital Terrestrial Multimedia Broadcasting (DTMB) signal. The received signal includes a plurality of signal frames. Each of the plurality of signal frames includes a frame body and a frame header. The frame header includes a pseudo-random noise sequence of symbols. Each pseudorandom noise sequence of the signal frame has a predetermined phase offset. According to an aspect of the invention, a first section of a symbol of a first pseudorandom noise sequence of the first signal frame and a second section of a symbol of a second pseudorandom noise sequence of the second signal frame are selected. In other words, the first and second segments are extracted from the pseudo random noise sequences of the frame headers of the first and second signal frames. The first and second pseudo-random noise sequences advantageously belong to (directly) consecutive (adjacent) signal frames of the same superframe. A phase difference between the first and second pseudorandom noise sequences is calculated based on the cyclic cross correlation of the first and second segments. The number of frames of the first signal frame and/or the second signal frame is calculated based on the determined phase difference. The method according to the invention is less complex than other methods and has good performance for systems that suffer from multipath fading, i.e. do not have a single output, such as Single Frequency Networks (SFNs).
The cyclic cross-correlation may be determined entirely in the time domain or at least partially in the frequency domain, typically by using a Fast Fourier Transform (FFT). Thus, the cyclic cross-correlation may comprise multiplying the symbols of the first segment with the complex conjugate of the corresponding symbols of the second segment in the time domain. In another embodiment, the step of determining the circular cross-correlation may comprise using a fast fourier transform. The symbols of the first and second segments may then be transformed into the frequency domain by a fast fourier transform. The circular cross-correlation may then be determined by multiplying the resulting coefficients of the fast fourier transform of one segment with the resulting system of the complex conjugate of the fast fourier transform of another segment. The result may be transformed into the time domain by an Inverse Fast Fourier Transform (IFFT). The fast fourier transform and the inverse fast fourier transform are thereby advantageously used for efficient numerical calculation of the cross-correlation.
The maximum of the circular cross-correlation function indicates the point in time (i.e. the amplitude or index) at which the signals are best aligned. In other words, the time delay between the two signals is determined by the magnitude of the maximum of the circular cross-correlation function. If the first segment is composed of r1Number of references and symbols is NPERAnd a second segment consisting of2Number of references and symbols is NPERThen the circular cross-correlation of the first and second segments can be expressed as the following equation (1):
Figure GDA0003332025060000021
n0.. for mPER-1
In the above formula (1), r* 2Indication r2And "mod" is the modulo operator. Exponent N and m combine modulo operator mod NPERProvided r* 2And (4) cyclic shift. The cyclic cross-correlation of the symbols of the first segment and the symbols of the second segment means that when N exceeds NPERCyclically shifting the complex conjugate symbol of one of the segments (here for the second segment) at-1 (each time n is reset to 0) such that during each cyclic shift the symbol of the symbol sequence of a respective segment (here the second segment) is cyclically shifted by one position.
Phase difference
Figure GDA0003332025060000022
It can then be determined according to equation (2):
Figure GDA0003332025060000031
exist of
Figure GDA0003332025060000032
And a one-to-one correspondence between the phases of the pseudo random noise sequences. Furthermore, the pseudo-random noise sequences of two adjacent/signal frames of the same superframe are also out of phase by two signal framesAn indicator of the number of signal frames. The number of signal frames is the count of signal frames within the superframe. The number of signal frames can then be determined by using a look-up table or using a set of formulas. The use of a look-up table may also support the speed and efficiency of the method.
The frame header is advantageously configured according to frame header mode PN420 or frame header mode PN945 of the digital terrestrial multimedia broadcasting standard.
Advantageously, the number of symbols (N) per segmentPER) May be less than the number of symbols of the pseudo random noise sequence of the frame header. For example, the number of symbols for the first and second segments may be less than 255 for PN420 or less than 511 for PN 945. This aspect also improves efficiency.
The invention also provides an apparatus, in particular a digital terrestrial multimedia broadcasting receiver or measuring device or analyzer, configured to perform the method steps described herein.
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Other aspects and features of the present invention will emerge from the following description of preferred embodiments with reference to the accompanying drawings, in which
FIG. 1 is a simplified diagram of an embodiment of the present invention, and
fig. 2 is a simplified diagram of a frame structure of a digital terrestrial multimedia broadcasting signal.
Detailed Description
Fig. 2 is a simplified diagram of a frame structure of a digital terrestrial multimedia broadcasting signal. There are four different types of frames shown in hierarchical order: daily frame CDF, subframe MF, superframe SUPF and signal frame SF.
The daily frame CDF has a duration of 24 hours and comprises 1440 framed MFs. Each subframe MF has a duration of exactly 1 minute and comprises 480 superframes SUPF. Each superframe SUPF has a duration of 125ms and comprises a number of signal frames SF, the number of signal frames SF depending on the duration of the signal frames. The signal frame SF is basically divided into two parts: a frame header FH and a frame body FB. The frame header FH includes a pseudo-random noise sequence (and a preamble and a postamble), and the frame body FB contains data blocks.
There are three different types of frame headers in the digital terrestrial multimedia broadcasting standard: a first type of "PN 420", a second type of "PN 595" and a third type of "PN 945". The present invention applies to both the first type PN420 and the third type PN 945. For PN420, signal frame SF has a duration of 555.6 μ s, for PN595, signal frame SF has a duration of 578.703 μ s, and for PN945, signal frame SF has a duration of 625 μ s, which correspond to 225, 216 and 200 signal frames SF for each superframe SUPF, respectively. The numbers "420" and "945" indicate the number of symbols. For example, the frame header of type PN420 has a preamble of 82 symbols, a pseudo-random noise sequence of 255 symbols, and a postamble of 83 symbols, i.e., a total of 420 symbols. The header of type PN945 has a preamble of 217 symbols, a pseudorandom noise sequence of 511 symbols, and a postamble of 217 symbols, i.e., 945 symbols in total.
The pseudorandom noise sequence is a binary pseudorandom noise sequence and has an autocorrelation that appears similar to a random binary sequence. The pseudo-random noise sequence may be generated by sequential logic circuitry, such as a Linear Feedback Shift Register (LFSR) implementing a particular generator polynomial. The LFSR is reset to an initial phase at the beginning of each superframe SUPF. The pseudo random noise sequences of each of the signal frames SF of the super frame SUPF differ by a predetermined phase shift. The LFSR determines the phase of the pseudo random noise sequence of each signal frame SF. For the frame header type PN420, 225 pseudo random noise sequences having different phases may be generated. For frame header type PN945, 200 pseudo random noise sequences with different phases may be generated. In other words, the phase shift of consecutive or adjacent pseudo random noise sequences and thus the phase difference between two consecutive pseudo random noise sequences is an indicator of the number of frames of the signal frame SF used within the superframe SUPF.
FIG. 1 is a simplified diagram of an embodiment of the present invention. The signal frames SF (k-1), SF (k), and SF (k +1) represent the extraction of a longer sequence of signal frames SF from the superframe SUPF. Since this embodiment requires two adjacent signal frames, only signal frame SF (k) and signal frame SF (k +1) will be discussed further. These signal frames are referred to as a first signal frame SF (k) and a second signal frame SF (k +1), while the actual number of frames of the signal frame SF (k) is of course at the signal levelThe entire sequence of number frames is arbitrary. The number of symbols of the signal frame SF is NFRAME. Each signal frame SF includes a frame header FH and a frame body FB. Therefore, there is a first header FH (k) and a first body FB (k) of the first signal frame SF (k) and a second header FH (k +1) and a first body FB (k +1) of the directly adjacent or consecutive second signal frame SF (k + 1). First segment r of consecutive symbols1Selected from (or extracted from) the first frame header fh (k). First section r1Number of symbols of (2) is NPER. Second segment r of consecutive symbols2Selected or extracted from the second frame header FH (k + 1). Second section r2Is also NPER. First section r1And a second segment r2Extracted from somewhere in the middle of each of the frame headers FH (k) and FH (k + 1). Number of symbols N per segmentPERThe number of symbols that can be smaller than the whole frame header FH (k) or FH (k +1), respectively. Also, the number of symbols N per segmentPERThe number of symbols that may be less than the pseudo-random noise sequence of each frame header is, for example, less than 255 for PN420 or less than 511 for PN 945.
First section r in the first frame header FH (k)1And the second section r in the second frame header FH (k +1)2Corresponds to (d). This is represented by the arrow N corresponding to the total or relative total length of the symbols of the signal frame SFFRAME. Thus, two segments r1And r2Each of which contains the same number N of symbolsPERWherein the symbols in each segment have corresponding positions in the corresponding first frame header FH (k) and second frame header FH (k +1), respectively.
The symbols of the first segment and/or the second segment may be filled with zero "0", thereby extending the length of the segment. This can be done on the segment r ready for fast fourier transform extraction1And r2Is useful or even necessary as this is known in the art. From a first section r1The resulting first sequence of spread symbols is then x1. From the second section r2The resulting second sequence of spread symbols is then x2。
First section r1(i.e. from the first segment r1Generated symbol sequence x1) And then transformed to the frequency domain by a fast fourier transform. Likewise, the second segment r2(i.e. from the second stage r2Generated symbol sequence x2) And then transformed to the frequency domain by a fast fourier transform. From the sequence x1And x2Are then respectively called X1And X2。
X1Complex conjugation of (which is X)1 *) Then with X2Multiplication. The result (X)1 *X2) Can be transformed back to the time domain by an inverse fast Fourier transform, resulting in a signal comprising r1And r2Cross correlation of
Figure GDA0003332025060000051
Y of w.
First section r1And a second segment r2Can also be expressed as:
Figure GDA0003332025060000052
Figure GDA0003332025060000053
the value W may then be expressed as
Figure GDA0003332025060000054
Figure GDA0003332025060000055
Is r1And r2Cross-correlation of (a):
Figure GDA0003332025060000056
0 … N for mPER-1
If the channel impulse response h is time invariant, then cross-correlation
Figure GDA0003332025060000061
Can utilize
Figure GDA0003332025060000062
And
Figure GDA0003332025060000063
but is simplified as follows:
Figure GDA0003332025060000064
S-Dis a length NPEROf a pseudo-random noise sequence
Figure GDA0003332025060000065
Cyclic shift of (2). The cyclic shift D of the pseudo random noise sequences of two adjacent signal frames is also the phase difference between the pseudo random noise sequences of adjacent signal frames SF (k) and SF (k + 1). Estimation of the phase shift between the pseudo-random noise sequences of two adjacent signal frames SF (k) and SF (k +1)
Figure GDA0003332025060000066
Can then be represented as
Figure GDA0003332025060000067
Due to the existence of
Figure GDA0003332025060000068
And pseudo-random noise sequences, the mapping or determination of the number of frames of a signal frame may be performed by using a look-up table or using a set of formulas.

Claims (7)

1. A method for pseudo-random noise (PN) phase detection of a received Digital Terrestrial Multimedia Broadcasting (DTMB) signal, wherein the received signal comprises a plurality of signal frames, and each of the plurality of signal frames comprises a frame header and a frame body, the frame header comprising a pseudo-random noise sequence of symbols, wherein each of the pseudo-random noise sequences of the signal frames has a predetermined phase shift, the method comprising: selecting a first segment of symbols of a first pseudorandom noise sequence of a first signal frame; selecting a second segment of symbols of a second pseudo-random noise sequence of a second frame, wherein the first and second pseudo-random noise sequences belong to directly consecutive signal frames and the first and second segments are extracted from somewhere in the middle of each of the frame headers and the position of the first segment within the first frame header corresponds to the position of the second segment within the second frame header, each of the two segments containing the same number of symbols; determining a phase difference between the first and second pseudorandom noise sequences based on the cyclic cross correlation of the first and second segments; and determining the number of frames of the first signal frame and/or the second signal frame based on the determined phase difference; wherein symbols are first extracted, having corresponding positions and having a number of symbols smaller than the frame header, then a series of cross-correlation steps are performed to obtain a cross-correlation result, and finally an estimate of the phase shift between the pseudo-random noise sequences of two adjacent signal frames is obtained based on the cross-correlation result.
2. The method of claim 1, wherein the circular cross-correlation comprises multiplying a symbol of the first segment with a complex conjugate of a corresponding symbol of the second segment.
3. The method of claim 1, wherein the circular cross-correlation comprises using a Fast Fourier Transform (FFT).
4. A method according to any of claims 1 to 3, wherein the number of frames is determined using a look-up table for mapping phase differences to number of frames.
5. The method according to any of claims 1 to 3, wherein the frame header is configured according to frame header type PN420 or frame header type PN945 of the digital terrestrial multimedia broadcasting standard.
6. The method according to any of claims 1 to 3, wherein the number of symbols per segment (N)PER) The number of symbols of the pseudo-random noise sequence smaller than the frame header is in particular smaller than 255 for the frame header type PN420 of the digital terrestrial multimedia broadcasting standard and smaller than 511 for the frame header type PN945 of the digital terrestrial multimedia broadcasting standard.
7. An apparatus, in particular a digital terrestrial multimedia broadcasting receiver or measuring device or analyzer, configured to perform the method according to any of the preceding claims.
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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0726658A2 (en) * 1995-02-10 1996-08-14 Nokia Mobile Phones Ltd. Symbol and frame synchronization in both a TDMA system and a CDMA system
CN101309251A (en) * 2008-06-13 2008-11-19 高拓讯达（北京）科技有限公司 PN sequence detection method and system of receiver based on DTTB standard
CN101321150A (en) * 2008-07-16 2008-12-10 清华大学 Combined synchronization process and its receiving terminal based on two-dimension short time slippage self-correlation
CN101588333A (en) * 2008-05-22 2009-11-25 赵力 Synchronization method suitable for terrestrial broadcasting national standard of Chinese digital televisions
CN101945065A (en) * 2010-08-27 2011-01-12 高拓讯达（北京）科技有限公司 Frequency deviation estimating method of receiver based on DTTB (Digital Television Terrestrial Broadcasting) standard

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20020122468A1 (en) * 2001-01-12 2002-09-05 Terion, Inc. Quasi orthogonal hybrid walsh-PN codes for CDMA application in HF modems
US7982861B2 (en) * 2008-07-31 2011-07-19 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Time delay and distance measurement
US9166776B2 (en) * 2013-10-04 2015-10-20 Amlogic Co., Ltd. Methods and systems for optimal PN phase detection in DTMB receivers

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0726658A2 (en) * 1995-02-10 1996-08-14 Nokia Mobile Phones Ltd. Symbol and frame synchronization in both a TDMA system and a CDMA system
CN101588333A (en) * 2008-05-22 2009-11-25 赵力 Synchronization method suitable for terrestrial broadcasting national standard of Chinese digital televisions
CN101309251A (en) * 2008-06-13 2008-11-19 高拓讯达（北京）科技有限公司 PN sequence detection method and system of receiver based on DTTB standard
CN101321150A (en) * 2008-07-16 2008-12-10 清华大学 Combined synchronization process and its receiving terminal based on two-dimension short time slippage self-correlation
CN101945065A (en) * 2010-08-27 2011-01-12 高拓讯达（北京）科技有限公司 Frequency deviation estimating method of receiver based on DTTB (Digital Television Terrestrial Broadcasting) standard

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