DVB frequency offset estimation method and device, equipment and storage medium

Abstract

The invention provides a DVB frequency offset estimation method and device, equipment and a storage medium. The method comprises the following steps: acquiring a waveform; performing time slot synchronization on double-speed time domain data received by a digital video broadcast reverse link baseband to obtain synchronized data; and performing frequency offset estimation according to the waveform and the first burst at the synchronization head of the synchronized data. According to the method, adaptive frequency offset estimation is carried out according to the waveform and the first burst at the synchronization head of the synchronized data, and the performance of a satellite communication system is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wireless communication, and in particular to a DVB frequency offset estimation method, device, equipment and storage medium. BACKGROUND

[0002] When estimating the frequency offset of the reverse link waveform of a DVB (Digital Video Broadcast) base station device, the relative movement of the satellite and the ground-based base station causes a Doppler shift in the transmission, which affects the reception performance.

[0003] Therefore, frequency offset estimation is required. SUMMARY

[0004] To solve one of the above technical defects, the present application provides a DVB frequency offset estimation method, device, equipment and storage medium.

[0005] In a first aspect, the present application provides a DVB frequency offset estimation method, which comprises:

[0006] Obtaining a waveform;

[0007] Performing time slot synchronization on 2x speed time domain data of a digital video broadcast reverse link baseband reception to obtain synchronized data;

[0008] Estimating the frequency offset according to the first burst at the synchronization header of the waveform and the synchronized data.

[0009] Optionally, estimating the frequency offset according to the first burst at the synchronization header of the waveform and the synchronized data comprises:

[0010] If the waveform is a quadrature phase shift keying waveform, extracting a 1x speed signal r(k) of the first burst at the synchronization header of the synchronized data; obtaining a demodulation signal z(k) = [r(k)] 4 ; determining a phase difference R m from the demodulation signal z(k); and estimating the frequency offset

[0011] wherein k is an index, O is the length of the 1x speed signal, f s is the symbol rate of the 1x speed signal, and arg{} is an amplitude angle function.

[0012] Optionally, determining the phase difference R m from the demodulation signal z(k) comprises:

[0013] Determining the phase difference

[0014] wherein i1 is an index, z(i1) is the signal at the i1 index in the demodulation signal, to demodulate the signal at the index conj() is conjugate.

[0015] Optionally, the frequency offset estimation is performed according to the first burst at the synchronization header of the data after synchronization, including:

[0016] If the waveform is not a quadrature phase shift keying waveform, and the waveform is a short burst waveform, a preamble symbol sequence c pre and a postamble symbol sequence c post corresponding to the waveform are obtained; a preamble symbol sequence b pre and a postamble symbol sequence b post are obtained from the first burst at the synchronization header of the data after synchronization; a demodulated preamble symbol sequence h pre = b pre *conj(c pre ) and a demodulated postamble symbol sequence h post = b post *conj(c post ) are obtained; a phase difference R pre is determined according to the demodulated preamble symbol sequence h post and the demodulated postamble symbol sequence h m ; and the frequency offset is estimated.

[0017] wherein conj() is conjugate, f s is a symbol rate of a 1x signal, m is a symbol interval between the preamble and the postamble, and arg{} is an argument function.

[0018] Optionally, the phase difference R m is determined according to the demodulated preamble symbol sequence h pre and the demodulated postamble symbol sequence h post , including:

[0019] The phase difference R

[0020] wherein i2 is an index, h pre (i2) is a symbol at the i2 index in the demodulated preamble symbol sequence, h post (i2) is a symbol at the i2 index in the demodulated postamble symbol sequence, and L0 is a minimum value of lengths of the preamble symbol sequence and the postamble symbol sequence.

[0021] Optionally, the frequency offset estimation is performed according to the first burst at the synchronization header of the data after synchronization, including:

[0022] If the waveform is not a quadrature phase shift keying waveform, and the waveform is not a short burst waveform, a pilot symbol sequence c pilot; obtaining a pilot symbol sequence b from the first burst at the synchronization header of the synchronized data pilot ; obtaining a demodulated pilot symbol sequence h pilot = b pilot * conj(c pilot ); determining a phase difference R pilot from the demodulated pilot symbol sequence h m ; estimating a frequency offset

[0023] wherein conj() is a conjugate, f s is a symbol rate of a 1x signal, n is a symbol interval between pilot symbols, L1 is a number of pilots, p is a number of pilots corresponding to the phase difference, and a default value of p is is a floor function, and arg{} is an argument function.

[0024] Optionally, the phase difference R m is determined from the demodulated pilot symbol sequence h pilot , comprising:

[0025] determining the phase difference

[0026] wherein l is an index, h pilot (l) is a symbol at the lth index in the demodulated pilot symbol sequence, and h pilot (l+L1-p) is a symbol at the l+L1-pth index in the demodulated pilot symbol sequence.

[0027] In a second aspect, the application provides a DVB frequency offset estimation device, comprising:

[0028] an acquisition module configured to acquire a waveform;

[0029] a synchronization module configured to perform time slot synchronization on 2x time domain data received by a digital video broadcast reverse link baseband, to obtain synchronized data;

[0030] an estimation module configured to perform frequency offset estimation according to the waveform and a first burst at a synchronization header of the synchronized data.

[0031] In a third aspect, the application provides an electronic device, comprising:

[0032] a memory;

[0033] a processor; and

[0034] a computer program;

[0035] wherein the computer program is stored in the memory and configured to be executed by the processor to implement the method of the first aspect.

[0036] In a fourth aspect, the present application provides a computer readable storage medium, having stored thereon a computer program; the computer program is executed by a processor to implement the method according to the first aspect.

[0037] The present application provides a DVB frequency offset estimation method, device, equipment and storage medium, the method comprising: acquiring a waveform; performing time slot synchronization on 2 times speed time domain data of digital video broadcast reverse link baseband receiving to obtain synchronized data; and performing frequency offset estimation according to the first burst at the synchronization header of the waveform and the synchronized data. The method of the present application performs adaptive frequency offset estimation according to the first burst at the synchronization header of the waveform and the synchronized data, and improves the performance of the satellite communication system. BRIEF DESCRIPTION OF DRAWINGS

[0038] The accompanying drawings, which are included to provide a further understanding of the present application and constitute a part of this application, illustrate certain illustrative embodiments of the present application and together with the description serve to explain the present application. In the drawings:

[0039] Figure 1 A flowchart of a DVB frequency offset estimation method provided by an embodiment of the present application;

[0040] Figure 2 A preamble symbol and a postamble symbol diagram provided by an embodiment of the present application;

[0041] Figure 3 Another preamble symbol and postamble symbol diagram provided by an embodiment of the present application;

[0042] Figure 4 A structure diagram of a DVB frequency offset estimation device provided by an embodiment of the present application;

[0043] Figure 5 A structure diagram of an electronic device provided by an embodiment of the present application. DETAILED DESCRIPTION

[0044] In order to make the technical solutions and advantages of the embodiments of the present application clearer, the following further describes the exemplary embodiments of the present application with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, and are not exhaustive of all embodiments. It should be noted that the embodiments and features in the embodiments can be combined with each other without conflict.

[0045] In the implementation of the present application, the inventor finds that, in the estimation of the reverse link waveform frequency offset of a DVB (Digital Video Broadcast) base station device, the relative movement of the satellite and the ground base station causes a Doppler frequency shift in the transmission, affecting the reception performance. Therefore, frequency offset estimation is required.

[0046] To solve the above problem, the present application provides a DVB frequency offset estimation method, device, equipment and storage medium. The method comprises: acquiring a waveform; performing time slot synchronization on 2x speed time domain data received by a digital video broadcast reverse link baseband, to obtain synchronized data; and performing frequency offset estimation according to the first burst at the synchronization header of the synchronized data and the waveform.

[0047] Referring to Figure 1 , the present application provides a DVB frequency offset estimation method, and the implementation process of the method is as follows:

[0048] 101, acquiring a waveform.

[0049] 102, performing time slot synchronization on 2x speed time domain data received by a digital video broadcast (DVB) reverse link baseband, to obtain synchronized data.

[0050] 103, performing frequency offset estimation according to the first burst at the synchronization header of the synchronized data and the waveform.

[0051] The implementation process of this step is as follows:

[0052] 1, if the waveform is a QPSK (Quadrature Phase Shift Keying) waveform, then:

[0053] (1) extracting a 1x speed signal r(k) of the first burst at the synchronization header of the synchronized data.

[0054] For example, r(k) = [e(pos 2X ), e(pos 2X +2), …, e(pos 2X +2*(O-1))] T .

[0055] wherein O is the length of the 1x speed signal, O = 1616 or 536.

[0056] (2) performing a demodulation operation on the entire waveform, and the waveform sequence is demodulated by taking the 4th power of the symbol, to obtain a demodulation signal z(k) = [r(k)]4 .

[0057] where k is an index, k = 0, 1, …, O-1.

[0058] (3) Determine the phase difference R from the demodulation signal z(k) m .

[0059] The phase difference can be obtained by correlating the first half and the second half of the burst. For example, determine the phase difference

[0060] where i1 is an index, z(i1) is the signal at the i1 index in the demodulation signal, z(i1+O) is the signal at the i1+O index in the demodulation signal, and conj() is the conjugate.

[0061] (4) Estimate the frequency offset

[0062] where f s is the symbol rate of the 1x signal, and arg{} is the argument function.

[0063] Since the symbol is a 4th power symbol, the phase change of each symbol point caused by the frequency offset is 4 times that of the original, so the estimated frequency offset is 4 times the real frequency offset.

[0064] If the waveform is a QPSK burst waveform, do not distinguish between pilots and data, calculate the 4th power of the signal, then correlate the first half and the second half of the burst signal to obtain the phase difference, and then calculate the frequency offset according to the phase difference. Since the symbol is a 4th power symbol, the estimated frequency offset is 4 times the real frequency offset, and the real frequency offset is further converted.

[0065] 2. If the waveform is not an orthogonal phase shift keying waveform, but the waveform is a short burst waveform (such as an 8PSK / 16QAM short burst waveform), then:

[0066] (1) Obtain the preamble symbol sequence c pre and the postamble symbol sequence c post corresponding to the waveform.

[0067] For example, obtain the locally stored preamble and postamble symbol sequences [c pre , c post ] corresponding to the burst waveform.

[0068] (2) Obtain the preamble symbol sequence b pre and the postamble symbol sequence b post from the first burst at the synchronization header of the synchronized data.

[0069] (3) Obtain the demodulation preamble symbol sequence h​pre =b pre *conj(c pre ) and the demodulation postleader symbol sequence h post =b post *conj(c post ).

[0070] Here, conj() represents conjugate.

[0071] (4) Based on the demodulation leader symbol sequence h pre and the demodulation postleader symbol sequence h post Determine the phase difference R m .

[0072] like Figure 2 As shown, L0 leading symbols (i.e.) can be used. Figure 2 Pre) and L0 postleader symbols (i.e. Figure 2 In the context of Post, calculate the phase difference between the preceding and following leaders with an interval of m symbols. For example, determine the phase difference.

[0073] Where i2 is the index, h pre (i2) represents the symbol at index i2 in the demodulation preamble symbol sequence, h post (i2) is the symbol at index i2 in the demodulated postlead symbol sequence, L0 is the minimum length of the prelead and postlead symbol sequences, and m is the symbol interval between the prelead and postlead symbol sequences.

[0074] (5) Estimating frequency offset

[0075] Where conj() is conjugate, f s is the symbol rate of the 1x speed signal, m is the symbol interval between the preamble and postamble, and arg{} is the argument function.

[0076] If the waveform is a short burst waveform of 8PSK / 16QAM, the frequency offset is estimated using pre- and post-leads. For example, the pre- and post-lead sequences stored locally are used for modulation, and the phase difference between the pre- and post-leads is obtained based on the demodulation result, thereby obtaining the frequency offset value.

[0077] 3. If the waveform is not a quadrature phase shift keying waveform, and the waveform is not a short burst waveform (such as a long burst waveform of 8PSK / 16QAM), then the first half and the second half of the pilot signals are used to estimate the frequency offset:

[0078] (1) Obtain the pilot symbol sequence c corresponding to the waveform. pilot .

[0079] For example, obtain the locally stored pilot symbol sequence c corresponding to the burst waveform ID. pilot.

[0080] (2) Obtain the pilot symbol sequence b from the first burst at the synchronization header of the synchronized data pilot .

[0081] (3) Obtain the demodulated pilot symbol sequence h pilot pilot *conj(c pilot ).

[0082] (4) Determine the phase difference R pilot from the demodulated pilot symbol sequence h m .

[0083] As shown in Figure 3 , p is the number of pilots corresponding to the phase difference, such as the number of front pilots (i.e., the first p pilots) or the number of rear pilots (i.e., the last p pilots). The calculation interval is the phase change between the first p pilots and the last p pilots, and then the phase difference R

[0084] wherein, l is an index, L1 is the number of pilots, h pilot (l) is the symbol at the lth index in the demodulated pilot symbol sequence, and h pilot (l+L1-p) is the symbol at the l+L1-pth index in the demodulated pilot symbol sequence.

[0085] p can be flexibly set, such as the default value of p is wherein, is a floor function.

[0086] If n is the symbol interval between pilot symbols, then the interval m between the front and rear pilot symbols of the phase is m=n*(L1-p).

[0087] (5) Estimate the frequency offset

[0088] wherein, conj() is a conjugate, f s is the symbol rate of a 1x signal, n is the symbol interval between pilot symbols, L1 is the number of pilots, p is the number of pilots corresponding to the phase difference, and arg{} is an argument function.

[0089] If it is an 8PSK / 16QAM long burst waveform, the middle pilot is used for frequency offset estimation, and the calculation interval is the phase change between the first p pilots and the last p pilots, and then the frequency offset value is obtained.

[0090] ​The DVB frequency offset estimation method provided in the embodiment can adaptively adopt different frequency offset estimation schemes according to different waveform characteristics under different waveform structures of a DVB reverse link, estimate the frequency offset by using a preamble, a postamble, a pilot and data, improve the precision of frequency offset estimation, and improve the performance of a satellite communication system.

[0091] The embodiment provides a DVB frequency offset estimation method, which comprises the following steps: acquiring a waveform; performing time slot synchronization on 2-times speed time domain data received by a digital video broadcast reverse link baseband to obtain synchronized data; and performing frequency offset estimation according to a first burst at a synchronization header of the synchronized data. The method provided in the embodiment performs adaptive frequency offset estimation according to the first burst at the synchronization header of the synchronized data, and improves the performance of a satellite communication system.

[0092] Based on the same inventive concept of the DVB frequency offset estimation method, the embodiment provides a DVB frequency offset estimation device, which is described with reference to Figure 4 The device comprises:

[0093] The acquisition module 401 is configured to acquire a waveform.

[0094] The synchronization module 402 is configured to perform time slot synchronization on 2-times speed time domain data received by a digital video broadcast reverse link baseband to obtain synchronized data.

[0095] The estimation module 403 is configured to perform frequency offset estimation according to a first burst at a synchronization header of the synchronized data.

[0096] The estimation module 403 is configured to extract a 1-times speed signal r(k) of the first burst at the synchronization header of the synchronized data if the waveform is a quadrature phase shift keying waveform, and obtain a demodulation signal z(k) = r(k) * r(k).

[0097] [r(k)] 4 According to the demodulation signal z(k), a phase difference R m is determined, and a frequency offset

[0098]

[0099] wherein k is an index, O is the length of the 1-times speed signal, f s is the symbol rate of the 1-times speed signal, and arg{} is an amplitude angle function.

[0100] According to the demodulation signal z(k), a phase difference R m is determined, and a frequency offset

[0101] The phase difference R

[0102] Where i1 is the index, and z(i1) is the signal at index i1 in the demodulated signal. For the first modulated signal The signal at the index, conj() is the conjugate.

[0103] The estimation module 403 is used to obtain the preamble symbol sequence c corresponding to the waveform if the waveform is not a quadrature phase shift keying waveform but is a short burst waveform. pre and the sequence of leading symbols c post Obtain the preamble symbol sequence b from the first burst at the synchronization header of the synchronized data. pre and the postleader sequence b post The demodulated preamble symbol sequence h is obtained. pre =b pre *conj(c pre ) and the demodulation postleader symbol sequence h post =b post *conj(c post According to the demodulation preamble sequence h) pre and the demodulation postleader symbol sequence h post Determine the phase difference R m Estimating frequency offset

[0104] Where conj() is conjugate, f s is the symbol rate of the 1x speed signal, m is the symbol interval between the preamble and postamble, and arg{} is the argument function.

[0105] Among them, according to the demodulation preamble sequence h pre and the demodulation postleader symbol sequence h post Determine the phase difference R m ,include:

[0106] Determine the phase difference

[0107] Where i2 is the index, h pre (i2) represents the symbol at index i2 in the demodulation preamble symbol sequence, h post (i2) is the symbol at index i2 in the demodulated postlead symbol sequence, and L0 is the minimum length of the prelead and postlead symbol sequences.

[0108] The estimation module 403 is used to obtain the pilot symbol sequence c corresponding to the waveform if the waveform is not a quadrature phase shift keying waveform and is not a short burst waveform. pilot The pilot symbol sequence b is obtained from the first burst at the synchronization header of the synchronized data. pilot The demodulated pilot symbol sequence h is obtained. pilot =bpilot conj(c pilot ). The phase difference R pilot is determined according to the demodulated pilot symbol sequence h m . The frequency offset is estimated

[0109] where conj() is a conjugate, f s is a symbol rate of a 1x signal, n is a symbol interval between pilot symbols, L1 is a pilot quantity, p is a pilot quantity corresponding to the phase difference, and a default value of p is is a floor function, and arg{} is an argument function.

[0110] The phase difference R m is determined according to the demodulated pilot symbol sequence h pilot , and includes:

[0111] The phase difference R m is determined according to the demodulated pilot symbol sequence h pilot , and includes:

[0112] where l is an index, h pilot (l) is a symbol at the lth index in the demodulated pilot symbol sequence, and h pilot (l+L1-p) is a symbol at the l+L1-pth index in the demodulated pilot symbol sequence.

[0113] The apparatus provided in the embodiment performs adaptive frequency offset estimation according to the first burst at the synchronization header of the waveform and the synchronized data, thereby improving the performance of the satellite communication system.

[0114] Based on the same inventive concept as the DVB frequency offset estimation method, the embodiment provides an electronic device, which, as shown in the figure, includes a memory 501, a processor 502, and a computer program. Figure 5 The computer program is stored in the memory 501 and is configured to be executed by the processor 502 to implement the above-mentioned DVB frequency offset estimation method.

[0115] Specifically,

[0116] The waveform is acquired.

[0117] The 2x time domain data of the digital video broadcast reverse link baseband reception is time slot synchronized to obtain synchronized data.

[0118] The frequency offset is estimated according to the first burst at the synchronization header of the waveform and the synchronized data.

[0119] The frequency offset is estimated according to the first burst at the synchronization header of the waveform and the synchronized data, and includes:

[0120] The frequency offset is estimated according to the first burst at the synchronization header of the waveform and the synchronized data, and includes:

[0121] If the waveform is a quadrature phase shift keying waveform, the 1x signal r(k) of the first burst at the sync header of the synchronized data is obtained. The demodulation signal z(k) = [r(k)] 4 is determined according to the demodulation signal z(k). m The frequency offset is estimated

[0122] where k is an index, O is the length of the 1x signal, f s is the symbol rate of the 1x signal, and arg{} is an argument function.

[0123] where the phase difference R m is determined according to the demodulation signal z(k).

[0124] The phase difference R

[0125] where i1 is an index, z(i1) is a signal at the i1 index in the demodulation signal, is a signal at the i1 index in the demodulation signal, and conj() is a conjugate.

[0126] where the frequency offset is estimated according to the waveform and the first burst at the sync header of the synchronized data, including:

[0127] If the waveform is not a quadrature phase shift keying waveform, but the waveform is a short burst waveform, the preamble symbol sequence c pre and the postamble symbol sequence c post corresponding to the waveform are obtained. The preamble symbol sequence b pre and the postamble symbol sequence b post are obtained from the first burst at the sync header of the synchronized data. The demodulated preamble symbol sequence h pre = b pre *conj(c pre ) and the demodulated postamble symbol sequence h post = b post *conj(c post ) are obtained. The phase difference R m is determined according to the demodulated preamble symbol sequence h pre and the demodulated postamble symbol sequence h post . The frequency offset is estimated

[0128] where conj() is a conjugate, f s is the symbol rate of the 1x signal, m is the symbol interval between the preamble and the postamble, and arg{} is an argument function.

[0129] where the phase difference R m is determined according to the demodulated preamble symbol sequence hpre and the demodulation postleader symbol sequence h post Determine the phase difference R m ,include:

[0130] Determine the phase difference

[0131] Where i2 is the index, h pre (i2) represents the symbol at index i2 in the demodulation preamble symbol sequence, h post (i2) is the symbol at index i2 in the demodulated postleading symbol sequence, and L0 is the minimum length of the preleading symbol sequence and the postleading symbol sequence.

[0132] The frequency offset estimation is performed based on the waveform and the first burst at the synchronization header of the synchronized data, including:

[0133] If the waveform is not a quadrature phase shift keying waveform and is not a short burst waveform, then obtain the pilot symbol sequence c corresponding to the waveform. pilot The pilot symbol sequence b is obtained from the first burst at the synchronization header of the synchronized data. pilot The demodulated pilot symbol sequence h is obtained. pilot =b pilot *conj(c piloi According to the demodulation pilot symbol sequence h pilot Determine the phase difference R m Estimating frequency offset

[0134] Where conj() is conjugate, f s Where is the symbol rate of the 1x speed signal, n is the symbol interval between pilot symbols, L1 is the number of pilots, and p is the number of pilots corresponding to the phase difference. The default value of p is 0. Here, arg{} is the floor function, and arg{} is the argument function.

[0135] Among them, according to the demodulation pilot symbol sequence h pilot Determine the phase difference R m ,include:

[0136] Determine the phase difference

[0137] Where l is the index, h pilot (l) represents the symbol at index l in the demodulation pilot symbol sequence, h pilot (l+L1-p) is the symbol at index l+L1-p in the demodulation pilot symbol sequence.

[0138] The electronic device provided in this embodiment has a computer program executed by a processor to perform adaptive frequency offset estimation based on the waveform and the first burst at the synchronization header of the synchronized data, thereby improving the performance of the satellite communication system.

[0139] Based on the same inventive concept as the DVB frequency offset estimation method, this embodiment provides a computer-readable storage medium on which a computer program is stored. The computer program is executed by a processor to implement the aforementioned DVB frequency offset estimation method.

[0140] Specifically,

[0141] Obtain the waveform.

[0142] Time-slot synchronization is performed on the 2x speed time-domain data received by the reverse link baseband of digital video broadcasting to obtain synchronized data.

[0143] Frequency offset is estimated based on the waveform and the first burst at the synchronization header of the synchronized data.

[0144] The frequency offset estimation is performed based on the waveform and the first burst at the synchronization header of the synchronized data, including:

[0145] If the waveform is a quadrature phase shift keying (QPSK) waveform, then extract the first burst of the 1x speed signal r(k) at the synchronization header of the synchronized data. This yields the demodulated signal z(k) = [r(k)]. 4 The phase difference R is determined based on the demodulation signal z(k). m Estimating frequency offset

[0146] Where k is the index, O is the length of the 1x speed signal, and f s Let be the symbol rate of the 1x speed signal, and arg{} be the argument function.

[0147] The phase difference R is determined based on the demodulation signal z(k). m ,include:

[0148] Determine the phase difference

[0149] Where i1 is the index, and z(i1) is the signal at index i1 in the demodulated signal. For the first modulated signal The signal at the index, conj() is the conjugate.

[0150] The frequency offset estimation is performed based on the waveform and the first burst at the synchronization header of the synchronized data, including:

[0151] If the waveform is not a quadrature phase shift keying waveform, but is a short burst waveform, then obtain the preamble symbol sequence c corresponding to the waveform. preand a postamble symbol sequence c post . A preambe symbol sequence b pre is obtained from the first burst at the sync header of the synchronized data post . A demodulated preambe symbol sequence h pre is obtained from the first burst at the sync header of the synchronized data pre = b pre *conj(c post ) and a demodulated postamble symbol sequence h post = b post *conj(c pre ). A phase difference R post is determined according to the demodulated preambe symbol sequence h m and the demodulated postamble symbol sequence h

[0152] where conj() is a conjugate, f s is a symbol rate of a 1x signal, m is a symbol interval between the preambe and the postamble, and arg{} is an argument function.

[0153] where a phase difference R pre is determined according to the demodulated preambe symbol sequence h post and the demodulated postamble symbol sequence h m , comprising:

[0154] determining the phase difference

[0155] where i2 is an index, h pre (i2) is a symbol at the i2 index in the demodulated preambe symbol sequence, h post (i2) is a symbol at the i2 index in the demodulated postamble symbol sequence, and L0 is a minimum of lengths of the preambe symbol sequence and the postamble symbol sequence.

[0156] where a frequency offset is estimated according to a waveform and a first burst at a sync header of synchronized data, comprising:

[0157] if the waveform is not a quadrature phase shift keying waveform and the waveform is not a short burst waveform, a pilot symbol sequence c pilot corresponding to the waveform is obtained. A pilot symbol sequence b pilot is obtained from the first burst at the sync header of the synchronized data. A demodulated pilot symbol sequence h pilot = b pilot *conj(c pilot ) is obtained. A phase difference R pilot is determined according to the demodulated pilot symbol sequence h m . A frequency offset is estimated

[0158] Wherein, conj() is conjugate, f s is the symbol rate of the 1x signal, n is the symbol interval between pilot symbols, L1 is the number of pilots, p is the number of pilots corresponding to the phase difference, and the default value of p is is the floor function, and arg{} is the argument function.

[0159] Wherein, according to the demodulation pilot symbol sequence h pilot determining the phase difference R m , comprising:

[0160] determining the phase difference

[0161] Wherein, l is the index, h pilot (l) is the symbol at the lth index in the demodulation pilot symbol sequence, h pilot (l+L1-p) is the symbol at the l+L1-pth index in the demodulation pilot symbol sequence.

[0162] The computer readable storage medium provided by the embodiment, and the computer program thereon are executed by a processor to perform adaptive frequency offset estimation according to the first burst at the synchronization header of the waveform and the synchronized data, thereby improving the performance of the satellite communication system.

[0163] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROMs, optical storage, etc.) containing computer-usable program code. The solutions in the embodiments of the present application can be implemented in various computer languages, such as the object-oriented programming language Java and the interpreted scripting language JavaScript.

[0164] The present application is described with reference to flowcharts and / or block diagrams according to the methods, devices (systems), and computer program products of the embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of flows and / or blocks in the flowcharts and / or block diagrams can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing apparatus to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing apparatus produce a device that implements the functions specified in the flowcharts and / or block diagrams. Figure 1 The functions specified in one or more flows and / or blocks Figure 1 The device that implements the functions specified in one or more flows and / or blocks.

[0165] These computer program instructions can also be stored in a computer- readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instructions which implement the Figure 1 function specified in the flow or flows and / or blocks Figure 1 of the block or blocks.

[0166] These computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions that are executed on the computer or other programmable apparatus provide steps for implementing the Figure 1 function specified in the flow or flows and / or blocks Figure 1 of the block or blocks.

[0167] Although preferred embodiments of the application have been described herein, substitutions and alterations are possible in view of the disclosure of this application without departing from the spirit and scope of the application. Therefore, it is intended that the appended claims be interpreted as including all such substitutions and alterations. What is claimed is:

[0168] Obviously, numerous modifications and variations of the present application are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims and their equivalents, the application can be practiced otherwise than as specifically described.

Claims

1. A method of DVB frequency offset estimation, characterized by, The method comprises: acquiring a waveform; performing time slot synchronization on 2-times speed time domain data of digital video broadcast reverse link baseband receiving to obtain synchronized data; performing frequency offset estimation according to the waveform and a first burst at a synchronization header of the synchronized data.

2. The method of claim 1, wherein, The frequency offset estimation according to the waveform and the first burst at the synchronization header of the synchronized data comprises: If the waveform is a quadrature phase shift keying waveform, a 1 times speed signal r(k) of the first burst at the synchronization header of the synchronized data is extracted; a demodulation signal z(k) = [r(k)] is obtained 4 ; a phase difference R m is determined according to the demodulation signal z(k); a frequency offset where k is an index, O is the length of the 1x signal, f s is the symbol rate of the 1x signal, and arg{} is the argument function.

3. The method of claim 2, wherein, determining the phase difference R from the demodulation signal z(k) m comprising: Determining phase difference wherein i1 is an index, z(i1) is a signal at the i1 index in the demodulated signal, is a signal at the i1 index in the demodulated signal, is a signal at the i1 index in the demodulated signal, conj() is a conjugate.

4. The method of claim 1, wherein, The frequency offset estimation according to the waveform and the first burst at the synchronization header of the synchronized data comprises: if the waveform is not a quadrature phase shift keying waveform, but the waveform is a short burst waveform, obtaining a preamble symbol sequence c corresponding to the waveform pre and a postamble symbol sequence c post ; obtaining a preamble symbol sequence b from a first burst at a synchronization header of the synchronized data pre and a postamble symbol sequence b post ; obtaining a de-modulated preamble symbol sequence h pre = b pre * conj(c pre ) and a de-modulated postamble symbol sequence h post = b post * conj(c post ); determining a phase difference R pre from the de-modulated preamble symbol sequence h post and the de-modulated postamble symbol sequence h m ; estimating a frequency offset where conj() is the conjugate, f s is the symbol rate of the 1x signal, m is the symbol spacing between the preamble and the post-amble, and arg{} is the argument function.

5. The method of claim 4, wherein, The sequence of pre-demodulation pilot symbols h pre and post-demodulation pilot symbols h post determining the phase difference R m comprising: Determining phase difference where i2 is an index, h pre (i2) is a symbol at the i2 index in the post-cursor symbol sequence, and L0 is the minimum of the lengths of the pre-cursor symbol sequence and the post-cursor symbol sequence. post (i2) is a symbol at the i2 index in the post-cursor symbol sequence, and L0 is the minimum of the lengths of the pre-cursor symbol sequence and the post-cursor symbol sequence.

6. The method of claim 1, wherein, The frequency offset estimation according to the waveform and the first burst at the synchronization header of the synchronized data comprises: If the waveform is a non-quadrature phase shift keying waveform, and the waveform is a non-short burst waveform, obtaining a pilot symbol sequence c corresponding to the waveform pilot ; obtaining a pilot symbol sequence b from a first burst at a synchronization header of the synchronized data pilot ; obtaining a de-modulated pilot symbol sequence h pilot = b pilot * conj(c pilot ); determining a phase difference R m from the de-modulated pilot symbol sequence h pilot ; estimating a frequency offset where conj() is conjugate, f s is the symbol rate of the 1x signal, n is the symbol spacing between pilot symbols, Li is the number of pilots, p is the number of pilots corresponding to the phase difference, and the default value of p is is the floor function, and arg{} is the argument function.

7. The method of claim 6, wherein, The sequence h of demodulation pilot symbols is determined according to pilot Determining the phase difference R m comprising: Determining phase difference wherein / is an index, h pilot (l) is the symbol at the / th index in the sequence of demodulated pilot symbols, h pilot (l+L1-p) is the symbol at the / +L1-pth index in the sequence of demodulated pilot symbols.

8. A DVB frequency offset estimation apparatus, characterized by, The apparatus comprises: an acquiring module configured to acquire a waveform; a synchronizing module configured to perform time slot synchronization on 2-times speed time domain data of digital video broadcast reverse link baseband receiving to obtain synchronized data; an estimating module configured to perform frequency offset estimation according to the waveform and a first burst at a synchronization header of the synchronized data.

9. An electronic device, comprising: comprise: a memory; a processor; and a computer program; wherein the computer program is stored in the memory and configured to be executed by the processor to implement the method of any one of claims 1-7. having a computer program stored thereon, the computer program being executable by a processor to implement the method of any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, ​

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