CN115412417B - Carrier initial phase determining method, device, terminal and storage medium - Google Patents
Carrier initial phase determining method, device, terminal and storage medium Download PDFInfo
- Publication number
- CN115412417B CN115412417B CN202210851570.6A CN202210851570A CN115412417B CN 115412417 B CN115412417 B CN 115412417B CN 202210851570 A CN202210851570 A CN 202210851570A CN 115412417 B CN115412417 B CN 115412417B
- Authority
- CN
- China
- Prior art keywords
- initial
- target channel
- channel phases
- phase
- determining
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000000034 method Methods 0.000 title claims abstract description 43
- 230000001360 synchronised effect Effects 0.000 claims abstract description 8
- 238000004590 computer program Methods 0.000 claims description 12
- 239000000969 carrier Substances 0.000 claims description 7
- 238000004364 calculation method Methods 0.000 abstract description 10
- 125000004122 cyclic group Chemical group 0.000 abstract description 8
- 238000012549 training Methods 0.000 abstract description 5
- 230000008569 process Effects 0.000 description 10
- 238000010586 diagram Methods 0.000 description 6
- 238000004891 communication Methods 0.000 description 5
- 230000006870 function Effects 0.000 description 4
- 230000010363 phase shift Effects 0.000 description 4
- 238000005070 sampling Methods 0.000 description 4
- 238000012935 Averaging Methods 0.000 description 3
- 230000001419 dependent effect Effects 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 230000004044 response Effects 0.000 description 2
- 239000000654 additive Substances 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000013500 data storage Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Classifications
-
- 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
- H04L27/2668—Details of algorithms
- H04L27/2669—Details of algorithms characterised by the domain of operation
- H04L27/2671—Time domain
-
- 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
- H04L27/2689—Link with other circuits, i.e. special connections between synchronisation arrangements and other circuits for achieving synchronisation
- H04L27/2695—Link with other circuits, i.e. special connections between synchronisation arrangements and other circuits for achieving synchronisation with channel estimation, e.g. determination of delay spread, derivative or peak tracking
Abstract
The application discloses a carrier initial phase determining method, a device, a terminal and a storage medium, wherein the method comprises the following steps: receiving an initial time domain signal; determining an LTF time domain signal based on the initial time domain signal; determining m target channel phases corresponding to m non-zero subcarriers based on the LTF time domain signals; and determining the initial carrier phase based on m target channel phases corresponding to the m non-zero subcarriers. The invention uses the inherent long training sequence in the lead of WLAN signal to take the phase after channel estimation, and takes the influence of synchronous timing error and cyclic delay into account to estimate the initial phase of carrier wave through operation. The method has the advantages of simple phase estimation calculation and higher accuracy.
Description
Technical Field
The present invention relates to the field of phase estimation technologies, and in particular, to a method, an apparatus, a terminal, and a storage medium for determining an initial phase of a carrier.
Background
When WLAN signals are transmitted, a certain phase difference exists between a carrier wave used for IQ modulation by a transmitting end and a carrier wave used for IQ demodulation by a receiving end. When the transmitting end has IQ imbalance, the phase difference may affect the estimation of the receiving end on IQ imbalance, thereby affecting the link performance. Therefore, how to accurately estimate the initial phase of the carrier becomes a problem to be solved.
At present, for the estimation of the initial phase of the carrier, the frame starting position is obtained mainly through synchronous detection, a long training sequence (Long Training Field, LTF) time domain sampling sequence of a received signal is taken out, then the phase of the LTF time domain sampling sequence of the received signal is taken out to be differenced with the local LTF time domain sampling sequence, the time domain phase difference of each sampling point is obtained, and then the time domain phase difference is averaged to obtain the estimated value of the initial phase of the carrier.
However, when the above method is applied to a signal with timing error or a MIMO signal with cyclic shift (Cyclic Shift Diversity, CSD), since different transmit antennas perform different time-domain cyclic shifts on LTFs, there is a cyclic delay between the LTFs of the received signal and the local LTFs, resulting in a problem that the accuracy of the calculated estimated value of the initial phase of the carrier is low.
Disclosure of Invention
The main objective of the present application is to provide a method, an apparatus, a terminal and a storage medium for determining a carrier initial phase, so as to solve the problem of low accuracy of a calculated estimated value of the carrier initial phase in the related art.
In order to achieve the above object, in a first aspect, the present application provides a carrier initial phase determining method, including:
receiving an initial time domain signal;
determining an LTF time domain signal based on the initial time domain signal;
determining m target channel phases corresponding to m non-zero subcarriers based on the LTF time domain signals, wherein the m non-zero subcarriers are in one-to-one correspondence with the m target channel phases, and m is an integer;
and determining the initial carrier phase based on m target channel phases corresponding to the m non-zero subcarriers.
In one possible implementation, determining the LTF time domain signal based on the initial time domain signal includes:
and carrying out synchronous timing estimation on the initial time domain signal to obtain an LTF time domain signal.
In one possible implementation, determining m target channel phases corresponding to m non-zero subcarriers based on the LTF time domain signal includes:
sequentially carrying out frequency offset estimation and frequency offset compensation on the LTF time domain signals to obtain LTF time domain signals subjected to frequency offset compensation;
and determining m target channel phases corresponding to m non-zero subcarriers based on the LTF time domain signals after frequency offset compensation.
In one possible implementation, determining m target channel phases corresponding to m non-zero subcarriers based on the LTF time domain signal after frequency offset compensation includes:
carrying out channel estimation on the LTF time domain signal subjected to frequency offset compensation to obtain m channel values corresponding to m non-zero subcarriers, wherein the m non-zero subcarriers are in one-to-one correspondence with the m channel values;
obtaining m phases corresponding to m channel values, and obtaining m initial channel phases corresponding to m non-zero subcarriers, wherein the m channel values are in one-to-one correspondence with the m phases and the m initial channel phases;
and removing phase rotation on the m initial channel phases to obtain m target channel phases, wherein the m initial channel phases and the m target channel phases are in one-to-one correspondence.
In one possible implementation, determining the carrier initial phase based on m target channel phases corresponding to m non-zero subcarriers includes:
and performing linear fitting on the m target channel phases to obtain the initial carrier phase.
In one possible implementation, m is an even number greater than or equal to 2;
performing linear fitting on m target channel phases to obtain carrier initial phases, including:
calculating the corresponding slopes of the phases of m target channels; determining m/2 initial channel phases corresponding to zero subcarriers based on the slope and m target channel phases;
and calculating the average value of m/2 initial channel phases to obtain a target channel phase corresponding to the zero subcarrier, and taking the target channel phase corresponding to the zero subcarrier as the carrier initial phase.
In one possible implementation, determining m/2 initial channel phases corresponding to zero subcarriers based on the slope and the m target channel phases includes:
selecting two symmetrical non-zero sub-carriers from the m target channel phases, and determining a reference value based on the slope and the two target channel phases;
selecting m-2 target channel phases except for the two target channel phases from the m target channel phases, and obtaining (m-2)/2 initial channel phases based on the m-2 target channel phases, the slope and the reference value;
and summarizing the reference value and the (m-2)/2 initial channel phases to obtain m/2 initial channel phases.
In a second aspect, an embodiment of the present invention provides a carrier initial phase determining apparatus, including:
a first signal receiving module for receiving an initial time domain signal;
a second signal determining module for determining an LTF time domain signal based on the initial time domain signal;
the channel phase determining module is used for determining m target channel phases corresponding to m non-zero subcarriers based on the LTF time domain signals, wherein the m non-zero subcarriers are in one-to-one correspondence with the m target channel phases, and m is an integer;
and the initial phase determining module is used for determining the initial phase of the carrier based on m target channel phases corresponding to m non-zero subcarriers.
In a third aspect, an embodiment of the present invention provides a terminal, including a memory, a processor, and a computer program stored in the memory and executable on the processor, the processor implementing the steps of any one of the carrier initial phase determining methods described above when executing the computer program.
In a fourth aspect, embodiments of the present invention provide a computer readable storage medium storing a computer program which, when executed by a processor, performs the steps of any one of the carrier initial phase determination methods described above.
The embodiment of the invention provides a method, a device, a terminal and a storage medium for determining an initial phase of a carrier, which comprise the following steps: the method comprises the steps of receiving an initial time domain signal, determining an LTF time domain signal based on the initial time domain signal, determining m target channel phases corresponding to m non-zero subcarriers based on the LTF time domain signal, and determining a carrier initial phase based on the m target channel phases corresponding to m non-zero subcarriers. The invention uses the inherent long training sequence in the lead of WLAN signal to take the phase after channel estimation, and takes the influence of synchronous timing error and cyclic delay into account to estimate the initial phase of carrier wave through operation. The method has the advantages of simple phase estimation calculation and higher accuracy.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this application, are included to provide a further understanding of the application and to provide a further understanding of the application with regard to the other features, objects and advantages of the application. The drawings of the illustrative embodiments of the present application and their descriptions are for the purpose of illustrating the present application and are not to be construed as unduly limiting the present application. In the drawings:
fig. 1 is a schematic diagram of a WLAN-oriented communication system model according to an embodiment of the present invention;
fig. 2 is a flowchart of an implementation of a method for determining an initial phase of a carrier according to an embodiment of the present invention;
fig. 3 is a schematic diagram of a target channel phase corresponding to a subcarrier provided in an embodiment of the present invention;
fig. 4 is a schematic structural diagram of a carrier initial phase determining device according to an embodiment of the present invention;
fig. 5 is a schematic diagram of a terminal according to an embodiment of the present invention.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
The terms "first," "second," "third," "fourth" and the like in the description and in the claims and in the above drawings, if any, are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that the embodiments of the invention described herein may be implemented in sequences other than those illustrated or otherwise described herein.
It should be understood that, in various embodiments of the present invention, the sequence number of each process does not mean that the execution sequence of each process should be determined by its functions and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.
It should be understood that in the present invention, "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements that are expressly listed or inherent to such process, method, article, or apparatus.
It should be understood that in the present invention, "plurality" means two or more. "and/or" is merely an association relationship describing an association object, and means that three relationships may exist, for example, and/or B may mean: a exists alone, A and B exist together, and B exists alone. The character "/" generally indicates that the context-dependent object is an "or" relationship. "comprising A, B and C", "comprising A, B, C" means that all three of A, B, C comprise, "comprising A, B or C" means that one of the three comprises A, B, C, and "comprising A, B and/or C" means that any 1 or any 2 or 3 of the three comprises A, B, C.
It should be understood that in the present invention, "B corresponding to a", "a corresponding to B", or "B corresponding to a" means that B is associated with a, from which B can be determined. Determining B from a does not mean determining B from a alone, but may also determine B from a and/or other information. The matching of A and B is that the similarity of A and B is larger than or equal to a preset threshold value.
As used herein, "if" may be interpreted as "at … …" or "at … …" or "in response to a determination" or "in response to detection" depending on the context.
The technical scheme of the invention is described in detail below by specific examples. The following embodiments may be combined with each other, and some embodiments may not be repeated for the same or similar concepts or processes.
For the purpose of making the objects, technical solutions and advantages of the present invention more apparent, the following description will be made by way of specific embodiments with reference to the accompanying drawings.
In the WLAN communication system model shown in fig. 1, a signal x is to be transmitted i (t) and x q (t) IQ modulation at the transmitting end, adding amplitude attenuation and Gaussian white noise (Additive White Gaussian Noise, AWGN), IQ demodulation at the receiving end to obtain a received signal y i (t) and y q (t)。
In the above process, there may be IQ imbalance at the transmitting end, and the amplitude factor and the phase factor of IQ imbalance are respectively set as ε and εThe carrier wave of the receiving end for IQ demodulation may have a frequency offset and an initial phase relative to the carrier wave of the transmitting end, the frequency offset is set to Δf, the initial phase is set to θ, and both the frequency offset Δf and the initial phase θ affect IQ imbalance estimation of the transmitting end.
Therefore, the receiving end is used as standard equipment to remove the influence of frequency offset and initial phase so as to estimate and compensate the IQ imbalance existing at the transmitting end and restore the original signal.
The present invention proposes a carrier initial phase determining method in which the present invention uses a long training sequence inherent in the preamble of a WLAN signal, removes the influence of a synchronization timing error and a cyclic delay, and has high estimation accuracy.
In one embodiment, as shown in fig. 2, there is provided a carrier initial phase determining method, including the steps of:
step S201: receiving an initial time domain signal;
step S202: an LTF time domain signal is determined based on the initial time domain signal.
The initial time domain signal may be a WLAN MIMO signal or a non-MIMO signal.
After the receiving end receives the initial time domain signal, the receiving end carries out synchronous timing estimation on the initial time domain signal, so that the position of the LTF time domain signal can be positioned, and then the LTF time domain signal is taken out, and the LTF time domain signal can be directly obtained.
Step S203: based on the LTF time domain signal, m target channel phases corresponding to the m non-zero subcarriers are determined.
Wherein, m non-zero sub-carriers are in one-to-one correspondence with m target channel phases, and m is an integer.
For determining m target channel phases corresponding to m non-zero subcarriers, frequency offset estimation and frequency offset compensation are sequentially carried out on the LTF time domain signals to obtain frequency offset compensated LTF time domain signals, and then the m target channel phases corresponding to m non-zero subcarriers are determined based on the frequency offset compensated LTF time domain signals.
Determining m target channel phases corresponding to m non-zero subcarriers based on the LTF time domain signals after frequency offset compensation, and carrying out channel estimation on the LTF time domain signals after frequency offset compensation to obtain m channel values corresponding to the m non-zero subcarriers, wherein the m non-zero subcarriers are in one-to-one correspondence with the m channel values; then obtaining m phases corresponding to m channel values, and obtaining m initial channel phases corresponding to m non-zero subcarriers, wherein the m channel values are in one-to-one correspondence with the m phases and the m initial channel phases; and finally, removing phase rotation on the m initial channel phases to obtain m target channel phases, wherein the m initial channel phases and the m target channel phases are in one-to-one correspondence.
In some embodiments, a procedure for determining m target channel phases corresponding to m non-zero subcarriers based on the LTF time domain signal is described with reference to fig. 3, which is specifically as follows:
taking the initial time domain signal as the WLAN signal and taking m as 52 as an example, after the LTF time domain signal is extracted from the WLAN signal, sequentially performing frequency offset estimation and frequency offset compensation on the LTF time domain signal to obtain the LTF time domain signal after frequency offset compensation. The frequency offset compensation can remove the frequency offset part after estimating the frequency offset by using an LTF delay correlation method.
Then, channel estimation is carried out on the LTF time domain signal after frequency offset compensation to obtain 52 channel values corresponding to 52 non-zero subcarriers, and then phases corresponding to each channel value are obtained, so that 52 initial channel phases corresponding to 52 non-zero subcarriers can be obtained.
Since the large bandwidth WLAN signals are transmitted with a known phase rotation added to each 20M signal, they should be preferentially removed after channel estimation. Therefore, the phase rotation on each of the 52 initial channel phases needs to be removed to obtain the target channel phase corresponding to each non-zero subcarrier.
Wherein the target channel phase phi (k) comprises: initial phase θ, phase shift due to IQ imbalance, and phase noise due to white noise. The phase shift due to IQ imbalance and the phase noise due to white noise are small compared to the initial phase θ, which is negligible here.
In addition, a typical WLAN receiver introduces synchronization timing errors and CSD if multiple antennas are present, in which case the target channel phase phi (k) will be added with a phase shift that is linearly dependent on frequency.
In summary, the calculation formula of the target channel phase Φ (k) can be expressed as:
where k is a subcarrier sequence number, Δn represents a time domain delay or a cyclic shift, and N represents the number of subcarriers of the FFT. At this time, the target channel phase Φ (k) varies linearly with frequency. Because phi (k) is E [ -pi, pi), when phi (k) is more than or equal to pi or phi (k) is less than-pi, jump occurs.
Step S104: and determining the initial carrier phase based on m target channel phases corresponding to the m non-zero subcarriers.
For determining the initial carrier phase, linear fitting is performed on m target channel phases to obtain the initial carrier phase, where m is an even number greater than or equal to 2.
Based on the phase characteristics, the phase value at 0 subcarrier is not affected by the linear phase change, and there is φ (0) ≡θ. Since the value of the 0 frequency point of the LTF is 0, it cannot be used for estimating the channel, and thus it is necessary to calculate the value of phi (0) by using a linear fitting method.
And performing linear fitting on the m target channel phases, namely calculating the slope corresponding to the m target channel phases, determining m/2 initial channel phases corresponding to the zero sub-carrier based on the slope and the m target channel phases, calculating the average value of the m/2 initial channel phases, obtaining the target channel phases corresponding to the zero sub-carrier, and taking the target channel phases corresponding to the zero sub-carrier as carrier initial phases.
Wherein determining m/2 initial channel phases corresponding to zero subcarriers based on the slope and the m target channel phases comprises: selecting two target channel phases corresponding to two symmetrical non-zero subcarriers from m target channel phases, determining a reference value based on the slope and the two target channel phases, selecting m-2 target channel phases except the two target channel phases from the m target channel phases, obtaining (m-2)/2 initial channel phases based on the m-2 target channel phases, the slope and the reference value, and summarizing the reference value and the (m-2)/2 initial channel phases to obtain m/2 initial channel phases.
In some embodiments, the process of linearly fitting the m target channel phases to obtain the initial carrier phase is described as follows:
as can be seen from fig. 3, there are several hopping points from-pi to pi for the target channel phase phi (k) for the non-zero sub-carriers. And segmenting phi (k) according to the jump points, wherein each segment does not have numerical jump, then calculating the slope of each segment respectively, calculating the average value to obtain the average slope, and recording the average slope as a slope (slope estimation value) kappa.
Then, a pair of symmetrical frequency points is taken, and the phase value at the 0 subcarrier is estimated according to the slope kappa, and is taken as a reference value. To reduce the effect of slope estimation errors, the closest center symmetric frequency point may be taken. The reference value can be used as a basis for evaluating whether phase deviation exists in the rest estimated values.
And taking other symmetrical frequency points, respectively estimating phase values at 0 sub-carriers, and carrying out phase deviation compensation according to the reference value. Since the slope estimation has a certain error range, the phase value at the 0 subcarrier is estimated by taking the average value of the symmetrical frequency points, and the influence of the slope error can not be introduced. Since the magnitude of the phase is limited in the range of [ -pi, pi), and the average value of the symmetrical frequency points may deviate from phi (0) by + -pi or even + -2 pi in consideration of phase jump caused by errors, compensation is required according to the reference value.
And (3) averaging the phase values at all 0 sub-carriers in the previous step to obtain the initial phase (estimated value) of the carrier. Compared with the reference value, the result after averaging can inhibit phase noise, reduce estimation error and make estimation result more accurate.
The invention estimates and compensates the frequency offset in advance, can resist the influence of synchronous timing error and CSD, adopts a multi-carrier averaging mode to reduce the phase shift and phase noise caused by IQ imbalance, and has good initial phase estimation effect. In addition, the calculation is simpler, the calculation cost is low, and the accuracy is higher.
It should be understood that the sequence number of each step in the foregoing embodiment does not mean that the execution sequence of each process should be determined by the function and the internal logic, and should not limit the implementation process of the embodiment of the present invention.
The following are device embodiments of the invention, for details not described in detail therein, reference may be made to the corresponding method embodiments described above.
Fig. 4 shows a schematic structural diagram of a carrier initial phase determining device according to an embodiment of the present invention, and for convenience of explanation, only a portion related to the embodiment of the present invention is shown, and the carrier initial phase determining device includes a first signal receiving module 41, a second signal determining module 42, a channel phase determining module 43, and an initial phase determining module 44, which are specifically as follows:
a first signal receiving module 41, configured to receive an initial time domain signal;
a second signal determining module 42, configured to determine an LTF time domain signal based on the initial time domain signal;
a channel phase determining module 43, configured to determine m target channel phases corresponding to m non-zero subcarriers based on the LTF time domain signal, where the m non-zero subcarriers are in one-to-one correspondence with the m target channel phases, and m is an integer;
an initial phase determining module 44 is configured to determine a carrier initial phase based on m target channel phases corresponding to m non-zero subcarriers.
In one possible implementation, the second signal determination module 42 includes:
and the second time domain information determining submodule is used for carrying out synchronous timing estimation on the initial time domain signal to obtain an LTF time domain signal.
In one possible implementation, the channel phase determination module 43 includes:
the frequency offset calculation sub-module is used for sequentially carrying out frequency offset estimation and frequency offset compensation on the LTF time domain signals to obtain the LTF time domain signals after frequency offset compensation;
and the channel phase determining submodule is used for determining m target channel phases corresponding to m non-zero subcarriers based on the LTF time domain signals after frequency offset compensation.
In one possible implementation, the channel phase determination submodule includes:
the channel estimation unit is used for carrying out channel estimation on the LTF time domain signal subjected to frequency offset compensation to obtain m channel values corresponding to m non-zero subcarriers, wherein the m non-zero subcarriers are in one-to-one correspondence with the m channel values;
the initial channel phase determining unit is used for obtaining m phases corresponding to m channel values and obtaining m initial channel phases corresponding to m non-zero subcarriers, wherein the m channel values are in one-to-one correspondence with the m phases and the m initial channel phases;
and the target channel phase determining unit is used for removing phase rotations on the m initial channel phases to obtain m target channel phases, wherein the m initial channel phases are in one-to-one correspondence with the m target channel phases.
In one possible implementation, the initial phase determination module 44 includes:
and the linear fitting sub-module is used for carrying out linear fitting on the m target channel phases to obtain the initial carrier phase.
In one possible implementation, m is an even number greater than or equal to 2;
the linear fitting submodule includes:
the slope calculating unit is used for calculating the slopes corresponding to the phases of the m target channels;
an initial channel phase calculation unit, configured to determine m/2 initial channel phases corresponding to zero subcarriers based on the slope and m target channel phases;
and the initial phase determining unit is used for calculating the average value of m/2 initial channel phases to obtain a target channel phase corresponding to the zero subcarrier, and taking the target channel phase corresponding to the zero subcarrier as the carrier initial phase.
In one possible implementation, the initial channel phase calculation unit includes:
a reference value calculation subunit, configured to select two target channel phases corresponding to two symmetrical non-zero subcarriers from the m target channel phases, and determine a reference value based on the slope and the two target channel phases;
an initial channel phase calculation subunit, configured to select m-2 target channel phases except for the two target channel phases from the m target channel phases, and obtain (m-2)/2 initial channel phases based on the m-2 target channel phases, the slope and the reference value;
and the initial channel phase determining subunit is used for summarizing the reference value and the (m-2)/2 initial channel phases to obtain m/2 initial channel phases.
Fig. 5 is a schematic diagram of a terminal according to an embodiment of the present invention. As shown in fig. 5, the terminal 5 of this embodiment includes: a processor 51, a memory 52 and a computer program 53 stored in the memory 52 and executable on the processor 51. The steps of the above embodiments of the carrier initial phase determination method are implemented by the processor 51 when executing the computer program 53, such as steps 201 to 204 shown in fig. 2. Alternatively, the processor 51 implements the functions of the modules/units in the respective carrier initial phase determining device embodiments described above, such as the functions of the modules/units 41 to 44 shown in fig. 4, when executing the computer program 53.
The present invention also provides a readable storage medium having a computer program stored therein, which when executed by a processor is configured to implement the carrier initial phase determination method provided in the above various embodiments.
The readable storage medium may be a computer storage medium or a communication medium. Communication media includes any medium that facilitates transfer of a computer program from one place to another. Computer storage media can be any available media that can be accessed by a general purpose or special purpose computer. For example, a readable storage medium is coupled to the processor such that the processor can read information from, and write information to, the readable storage medium. In the alternative, the readable storage medium may be integral to the processor. The processor and the readable storage medium may reside in an application specific integrated circuit (Application Specific Integrated Circuits, ASIC). In addition, the ASIC may reside in a user device. The processor and the readable storage medium may reside as discrete components in a communication device. The readable storage medium may be read-only memory (ROM), random-access memory (RAM), CD-ROMs, magnetic tape, floppy disk, optical data storage device, etc.
The present invention also provides a program product comprising execution instructions stored in a readable storage medium. The at least one processor of the apparatus may read the execution instructions from the readable storage medium, and execution of the execution instructions by the at least one processor causes the apparatus to implement the carrier initial phase determination method provided by the various embodiments described above.
In the above described embodiments of the apparatus, it is understood that the processor may be a central processing unit (Central Processing Unit, CPU), but may also be other general purpose processors, digital signal processors (Digital Signal Processor, DSP), application specific integrated circuits (Application Specific Integrated Circuit, ASIC), etc. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like. The steps of a method disclosed in connection with the present invention may be embodied directly in a hardware processor for execution, or in a combination of hardware and software modules in a processor for execution.
The above embodiments are only for illustrating the technical solution of the present invention, and are not limiting; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention, and are intended to be included in the scope of the present invention.
Claims (7)
1. A method for determining an initial phase of a carrier, comprising:
receiving an initial time domain signal;
determining an LTF time domain signal based on the initial time domain signal;
determining m target channel phases corresponding to m non-zero subcarriers based on the LTF time domain signals, wherein the m non-zero subcarriers are in one-to-one correspondence with the m target channel phases, and m is an integer;
determining a carrier initial phase based on m target channel phases corresponding to the m non-zero subcarriers;
the determining the initial carrier phase based on the m target channel phases corresponding to the m non-zero subcarriers includes:
performing linear fitting on the m target channel phases to obtain the carrier initial phase;
wherein m is an even number greater than or equal to 2;
the linear fitting is performed on the m target channel phases to obtain the carrier initial phase, including:
calculating the corresponding slopes of the m target channel phases; determining m/2 initial channel phases corresponding to zero subcarriers based on the slope and the m target channel phases;
calculating the average value of the m/2 initial channel phases to obtain a target channel phase corresponding to the zero subcarrier, and taking the target channel phase corresponding to the zero subcarrier as the carrier initial phase;
the determining m/2 initial channel phases corresponding to the zero sub-carriers based on the slope and the m target channel phases includes:
selecting two symmetrical target channel phases corresponding to non-zero subcarriers from the m target channel phases, and determining a reference value based on the slope and the two target channel phases;
selecting m-2 target channel phases other than the two target channel phases from the m target channel phases, and obtaining (m-2)/2 initial channel phases based on the m-2 target channel phases, the slope and the reference value;
and summarizing the reference value and the (m-2)/2 initial channel phases to obtain the m/2 initial channel phases.
2. The carrier-initial-phase determination method of claim 1, wherein the determining the LTF time-domain signal based on the initial time-domain signal comprises:
and carrying out synchronous timing estimation on the initial time domain signal to obtain the LTF time domain signal.
3. The carrier-initial-phase determining method of claim 2, wherein determining m target channel phases corresponding to m non-zero subcarriers based on the LTF time-domain signal comprises:
sequentially carrying out frequency offset estimation and frequency offset compensation on the LTF time domain signals to obtain LTF time domain signals subjected to frequency offset compensation; and determining m target channel phases corresponding to the m non-zero subcarriers based on the LTF time domain signals after the frequency offset compensation.
4. The method of determining a carrier initial phase as claimed in claim 3, wherein determining m target channel phases corresponding to the m non-zero subcarriers based on the LTF time domain signal after the frequency offset compensation comprises:
performing channel estimation on the LTF time domain signal subjected to frequency offset compensation to obtain m channel values corresponding to the m non-zero subcarriers, wherein the m non-zero subcarriers are in one-to-one correspondence with the m channel values;
obtaining m phases corresponding to the m channel values, and obtaining m initial channel phases corresponding to the m non-zero subcarriers, wherein the m channel values are in one-to-one correspondence with the m phases and the m initial channel phases;
and removing phase rotations on the m initial channel phases to obtain m target channel phases, wherein the m initial channel phases and the m target channel phases are in one-to-one correspondence.
5. A carrier initial phase determining apparatus, comprising:
a first signal receiving module for receiving an initial time domain signal;
a second signal determining module, configured to determine an LTF time domain signal based on the initial time domain signal;
the channel phase determining module is used for determining m target channel phases corresponding to m non-zero subcarriers based on the LTF time domain signals, wherein the m non-zero subcarriers are in one-to-one correspondence with the m target channel phases, and m is an integer;
an initial phase determining module, configured to determine a carrier initial phase based on m target channel phases corresponding to the m non-zero subcarriers;
the determining the initial carrier phase based on the m target channel phases corresponding to the m non-zero subcarriers includes:
performing linear fitting on the m target channel phases to obtain the carrier initial phase;
wherein m is an even number greater than or equal to 2;
the linear fitting is performed on the m target channel phases to obtain the carrier initial phase, including:
calculating the corresponding slopes of the m target channel phases; determining m/2 initial channel phases corresponding to zero subcarriers based on the slope and the m target channel phases;
calculating the average value of the m/2 initial channel phases to obtain a target channel phase corresponding to the zero subcarrier, and taking the target channel phase corresponding to the zero subcarrier as the carrier initial phase;
the determining m/2 initial channel phases corresponding to the zero sub-carriers based on the slope and the m target channel phases includes:
selecting two symmetrical target channel phases corresponding to non-zero subcarriers from the m target channel phases, and determining a reference value based on the slope and the two target channel phases;
selecting m-2 target channel phases other than the two target channel phases from the m target channel phases, and obtaining (m-2)/2 initial channel phases based on the m-2 target channel phases, the slope and the reference value;
and summarizing the reference value and the (m-2)/2 initial channel phases to obtain the m/2 initial channel phases.
6. A terminal comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that the processor implements the steps of the carrier initial phase determination method according to any one of claims 1 to 4 when the computer program is executed.
7. A computer readable storage medium storing a computer program, characterized in that the computer program when executed by a processor implements the steps of the carrier initial phase determination method according to any one of claims 1 to 4.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210851570.6A CN115412417B (en) | 2022-07-19 | 2022-07-19 | Carrier initial phase determining method, device, terminal and storage medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210851570.6A CN115412417B (en) | 2022-07-19 | 2022-07-19 | Carrier initial phase determining method, device, terminal and storage medium |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115412417A CN115412417A (en) | 2022-11-29 |
| CN115412417B true CN115412417B (en) | 2024-04-02 |
Family
ID=84157001
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210851570.6A Active CN115412417B (en) | 2022-07-19 | 2022-07-19 | Carrier initial phase determining method, device, terminal and storage medium |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115412417B (en) |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1881970A (en) * | 2005-06-13 | 2006-12-20 | 北京中电华大电子设计有限责任公司 | Method and apparatus for compensating sampling frequency offset and carrier frequency offset in OFDM system |
| WO2016068666A1 (en) * | 2014-10-31 | 2016-05-06 | 엘지전자 주식회사 | Blind cfo estimation method in wireless communication system using bpsk or qbpsk scheme |
| CN106330806A (en) * | 2016-09-13 | 2017-01-11 | 广东顺德中山大学卡内基梅隆大学国际联合研究院 | Fine frequency deviation estimation algorithm and fine frequency deviation estimation system based on cyclic prefix and long training sequence field |
| CN108270701A (en) * | 2017-12-29 | 2018-07-10 | 武汉大学 | One kind is suitable for WiFi external illuminators-based radar direct wave suppressing methods |
| CN110113276A (en) * | 2018-02-01 | 2019-08-09 | 珠海全志科技股份有限公司 | OFDM frequency deviation estimating method, system and device based on IEEE802.11 |
| CN111245764A (en) * | 2020-01-14 | 2020-06-05 | 北京联盛德微电子有限责任公司 | Frequency offset tracking method and device based on WIFI system |
| CN112583749A (en) * | 2020-12-30 | 2021-03-30 | 深圳市极致汇仪科技有限公司 | Channel estimation improvement method and system suitable for tester |
| CN112866163A (en) * | 2021-01-06 | 2021-05-28 | 深圳市极致汇仪科技有限公司 | Method and system for estimating residual frequency offset of WiFi service |
| CN114301745A (en) * | 2021-12-24 | 2022-04-08 | 深圳市联平半导体有限公司 | Method and device for determining carrier frequency offset and sampling frequency offset |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7224666B2 (en) * | 2002-05-13 | 2007-05-29 | Texas Instruments Incorporated | Estimating frequency offsets using pilot tones in an OFDM system |
| US20040202234A1 (en) * | 2003-04-11 | 2004-10-14 | Agency For Science, Technology And Research | Low-complexity and fast frequency offset estimation for OFDM signals |
| GB2422073B (en) * | 2005-01-07 | 2007-03-28 | Toshiba Res Europ Ltd | Improved frequency offset tracking |
| US7813442B2 (en) * | 2006-10-30 | 2010-10-12 | Broadcom Corporation | MIMO channel estimation in presence of carrier frequency offset |
| CN102792655B (en) * | 2010-01-22 | 2016-10-12 | 索尼公司 | OFDM transmission in multi-carrier data transmission systems and reception equipment, method and system |
| US8879472B2 (en) * | 2011-04-24 | 2014-11-04 | Broadcom Corporation | Long training field (LTF) for use within single user, multiple user, multiple access, and/or MIMO wireless communications |
-
2022
- 2022-07-19 CN CN202210851570.6A patent/CN115412417B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1881970A (en) * | 2005-06-13 | 2006-12-20 | 北京中电华大电子设计有限责任公司 | Method and apparatus for compensating sampling frequency offset and carrier frequency offset in OFDM system |
| WO2016068666A1 (en) * | 2014-10-31 | 2016-05-06 | 엘지전자 주식회사 | Blind cfo estimation method in wireless communication system using bpsk or qbpsk scheme |
| CN106330806A (en) * | 2016-09-13 | 2017-01-11 | 广东顺德中山大学卡内基梅隆大学国际联合研究院 | Fine frequency deviation estimation algorithm and fine frequency deviation estimation system based on cyclic prefix and long training sequence field |
| CN108270701A (en) * | 2017-12-29 | 2018-07-10 | 武汉大学 | One kind is suitable for WiFi external illuminators-based radar direct wave suppressing methods |
| CN110113276A (en) * | 2018-02-01 | 2019-08-09 | 珠海全志科技股份有限公司 | OFDM frequency deviation estimating method, system and device based on IEEE802.11 |
| CN111245764A (en) * | 2020-01-14 | 2020-06-05 | 北京联盛德微电子有限责任公司 | Frequency offset tracking method and device based on WIFI system |
| CN112583749A (en) * | 2020-12-30 | 2021-03-30 | 深圳市极致汇仪科技有限公司 | Channel estimation improvement method and system suitable for tester |
| CN112866163A (en) * | 2021-01-06 | 2021-05-28 | 深圳市极致汇仪科技有限公司 | Method and system for estimating residual frequency offset of WiFi service |
| CN114301745A (en) * | 2021-12-24 | 2022-04-08 | 深圳市联平半导体有限公司 | Method and device for determining carrier frequency offset and sampling frequency offset |
Non-Patent Citations (3)
| Title |
|---|
| Pilot-symbol-aided channel estimation for OFDM in wireless systems;Y.Li;《IEEE Transactions on Vehicular Technology》;全文 * |
| 基于IEEE802.11a标准的信道估计算法的研究;卢易苏;《科协论坛》;全文 * |
| 面向IEEE802.11ac射频一致性测试的载波频偏估计算法研究与应用;张田静;《万方学位论文》;全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115412417A (en) | 2022-11-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US11108612B2 (en) | Anti-interference signal detection and synchronization method for wireless broadband communication system | |
| KR100719112B1 (en) | Sampling frequency offset estimation apparatus to be applied OFDM system and method thereof | |
| US8054914B2 (en) | Noise variance estimation | |
| KR100719111B1 (en) | Phaase noise compensation apparatus to be applied OFDM system and method thereof | |
| CN110636024B (en) | 5G waveform system synchronization method based on index modulation | |
| US7894539B2 (en) | Method and device for estimating integer carrier frequency offset | |
| EP2008417A1 (en) | Apparatus for estimating and compensating carrier frequency offset and data receiving method in receiver of wireless communication system | |
| WO2010060732A1 (en) | Frequency offset estimation | |
| JPH11186985A (en) | Method and device for estimating simple frequency offset in ofdm receiver | |
| US8059736B2 (en) | Orthogonal frequency division multiplexing receiver | |
| US20080273646A1 (en) | Sampling clock offset tracking and symbol re-timing | |
| CN112054983B (en) | Signal amplitude processing method and device of OFDM receiver and terminal equipment | |
| US8891706B2 (en) | System and method for optimizing use of channel state information | |
| CN115412417B (en) | Carrier initial phase determining method, device, terminal and storage medium | |
| CN112422472A (en) | Joint frequency offset estimation method and system | |
| KR20060067034A (en) | Method for estimating frequency/time offset and its using apparatus in ofdm communication system | |
| JP5055239B2 (en) | OFDM demodulator | |
| US8023576B2 (en) | Apparatus and method to estimate sampling offset | |
| CN113259281B (en) | DMRS (demodulation reference signal) and PTRS (packet transport reference signal) joint channel estimation method, device and receiver | |
| CN113141324A (en) | Channel estimation method and device | |
| CN114257479A (en) | Frequency offset estimation method and device, storage medium and terminal | |
| CN112995078A (en) | Frequency offset compensation algorithm of OFDMA uplink | |
| KR20150038841A (en) | Apparatus for estimating channel considering residual synchronization offset and method thereof | |
| CN114884788B (en) | Frequency offset estimation method and frame synchronization method | |
| CN116132228B (en) | Channel time offset compensation method and device based on multi-user SRS |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |