阅读说明：本技术 一种无数据辅助频偏估计方法及装置 (A kind of non-data aided frequency deviation estimating method and device ) 是由 李薿 于 2019-07-12 设计创作，主要内容包括：一种无数据辅助频偏估计方法,其特征在于,包括以下步骤：将当前时刻的接收符号与上一个时刻的接收符号进行差分处理,获得差分信号；对所述差分信号进行判决处理,获得判决差分符号并作为本地差分符号；将所述本地差分符号与所述差分信号进行去调制处理,获得去调制信号；对所述去调制信号进行相位提取,获得瞬时频偏误差造成的相位；根据所述相位计算瞬时频偏。一种无数据辅助频偏估计装置,包括差分模块,判决模块,去调制模块,相位提取模块,频偏计算模块。在一定的信噪比条件下,将所有接收符号都当成已知符号,通过判决符号的差分值,达到数据辅助的频偏估计算法效果。(A kind of non-data aided frequency deviation estimating method, which comprises the following steps: current time was received into symbol and the reception symbol at upper moment progress difference processing, obtains differential signal；Processing is made decisions to the differential signal, obtains judgement differential code and as local differential code；The local differential code and the differential signal are subjected to modulation treatment, modulated signal is gone in acquisition；It goes modulated signal to carry out phase extraction to described, obtains phase caused by instantaneous frequency deviation error；According to the phase calculation instantaneous frequency deviation.A kind of non-data aided frequency deviation estimation device, including difference block, judging module go modulation module, phase extraction module, frequency offset calculation module.Under the conditions of certain signal-to-noise ratio, all reception symbols are all treated as into known symbol, by adjudicating the difference value of symbol, reach data-aided frequency excursion algorithm effect.)

1. a kind of non-data aided frequency deviation estimating method, which comprises the following steps:

Current time was received into symbol and the reception symbol at upper moment progress difference processing, obtains differential signal；

Processing is made decisions to the differential signal, obtains judgement differential code and as local differential code；

The local differential code and the differential signal are subjected to modulation treatment, modulated signal is gone in acquisition；

It goes modulated signal to carry out phase extraction to described, obtains phase caused by instantaneous frequency deviation error；

According to the phase calculation instantaneous frequency deviation.

2. non-data aided frequency deviation estimating method according to claim 1, it is characterised in that: carrying out the difference processing Before, the reception symbol at a upper moment is initialized.

3. non-data aided frequency deviation estimating method according to claim 1, it is characterised in that: carrying out the difference processing Before, the modulating mode for receiving symbol is judged:

If the modulating mode is high order modulation, after first carrying out the transformation of QPSK constellation to the reception symbol, then carry out described Difference processing；

If the modulating mode is not high order modulation, the difference processing is directly carried out.

4. non-data aided frequency deviation estimating method according to claim 2, it is characterised in that: carrying out the initialization Before, the modulating mode for receiving symbol is judged:

If the modulating mode is high order modulation, after first carrying out the transformation of QPSK constellation to the reception symbol, then carry out described Initialization；

If the modulating mode is not high order modulation, the initialization is directly carried out.

5. non-data aided frequency deviation estimating method described according to claim 1~any one of 4, it is characterised in that:

If the instantaneous frequency deviation at k moment is Δ f_k, k >=0；

The difference processing, using formula diff (k)=z'(k) [z'(k-1)]^*；

The decision process, using formula

It is described to go modulation treatment, using formula dem (k)=diff (k) dec^*(k)；

The phase extraction, using formula Δ θ=Im { dem (k) }；

The calculating instantaneous frequency deviation, using formula

6. non-data aided frequency deviation estimating method according to claim 3 or 4, it is characterised in that:

Constellation transformation, using formula z'(k)=| z (k) | e^{j∠z(k)·Q+jβ}, wherein | z (k) |, ∠ z long for the mould of z (k) (k) phase for being z (k), z (k) are to receive symbol.

7. a kind of non-data aided frequency deviation estimation device characterized by comprising

The reception symbol and the reception symbol of last moment at current time are carried out difference processing by difference block, obtain difference letter Number；

Judging module, for making decisions processing to the differential signal, obtaining judgement differential code and being accorded with as local difference Number；

Modulation module is removed, for the local differential code and the differential signal to be carried out modulation treatment, acquisition goes to modulate Signal；

Phase extraction module obtains phase caused by instantaneous frequency deviation error for going modulated signal to carry out phase extraction to described；

Frequency offset calculation module, for according to the phase calculation instantaneous frequency deviation.

8. non-data aided frequency deviation estimation device according to claim 7, which is characterized in that further include

Initialization module was initialized for the reception symbol to a upper moment.

9. non-data aided frequency deviation estimation device according to claim 7 or 8, which is characterized in that further include:

Judgment module, for judging the modulating mode for receiving symbol；

Conversion module, for carrying out the transformation of QPSK constellation to the reception symbol for being judged as high order modulation by the judgment module.

Technical field

The present invention relates to Carrier Synchronization more particularly to a kind of non-data aided frequency deviation estimating methods and device.

Background technique

In digital communication systems, demodulation mode determines the performance of digital modulation system.Frequency locking ring in carrier synchronization is An indispensable part in continuous communiction system carries out tracking lock to the frequency deviation of variation, then compensates.In order to It is enough preferably to compensate, it needs to carry out effective, accurately estimation to frequency deviation using frequency excursion algorithm, in view of this, proposing this Invention.

Summary of the invention

The present invention provides a kind of non-data aided frequency deviation estimating method and device, under the conditions of certain signal-to-noise ratio, by institute There is reception symbol all to treat as known symbol, by adjudicating the difference value of symbol, reaches data-aided frequency excursion algorithm effect.

The present invention utilizes the characteristic of QPSK modulation constellation, makes decisions to differentiated symbol, estimates differential code, Ground connection carries out data-aided offset estimation.

Specifically use following technology:

A kind of non-data aided frequency deviation estimating method, which comprises the following steps:

Current time was received into symbol and the reception symbol at upper moment progress difference processing, obtains differential signal；

Processing is made decisions to the differential signal, obtains judgement differential code and as local differential code；

The local differential code and the differential signal are subjected to modulation treatment, modulated signal is gone in acquisition；

It goes modulated signal to carry out phase extraction to described, obtains phase caused by instantaneous frequency deviation error；

According to the phase calculation instantaneous frequency deviation.

Further, before carrying out the difference processing, the reception symbol at a upper moment was initialized.

Further, before carrying out the difference processing, the modulating mode for receiving symbol is judged:

If the modulating mode is high order modulation, after first carrying out the transformation of QPSK constellation to the reception symbol, then carry out The difference processing；

If the modulating mode is not high order modulation, the difference processing is directly carried out.

Further, the modulating mode judgement and constellation conversion process, can also carry out before an initialization:

If the modulating mode is high order modulation, after first carrying out the transformation of QPSK constellation to the reception symbol, then carry out The initialization；

If the modulating mode is not high order modulation, the initialization is directly carried out.

Present invention simultaneously provides a kind of non-data aided frequency deviation estimation devices, which is characterized in that including

The reception symbol and the reception symbol of last moment at current time are carried out difference processing by difference block, and it is poor to obtain Sub-signal；

Judging module obtains judgement differential code and as local poor for making decisions processing to the differential signal Divide symbol；

Modulation module is removed, for the local differential code and the differential signal to be carried out modulation treatment, is gone Modulated signal；

Phase extraction module, for going modulated signal to carry out phase extraction to described, caused by obtaining instantaneous frequency deviation error Phase；

Frequency offset calculation module, for according to the phase calculation instantaneous frequency deviation.

Further, further include initialization module, initialized for the reception symbol to a upper moment.

Further, further includes: judgment module, for judging the modulating mode for receiving symbol；Conversion module, For carrying out the transformation of QPSK constellation to the reception symbol for being judged as high order modulation by the judgment module.

The invention has the advantages that:

Under the conditions of certain signal-to-noise ratio, reach data-aided frequency discrimination algorithm effect, data resource utilization rate 100%, Algorithm complexity is low, is easy to be engineered；

Using the characteristic of QPSK modulation constellation, differentiated symbol is made decisions, estimates differential code, indirectly into The data-aided offset estimation of row.

Detailed description of the invention

Fig. 1 is the frame format figure of continuous communiction.

Fig. 2 is the flow chart of non-data aided frequency deviation estimating method embodiment of the present invention.

Fig. 3 is second-order proportional-plus-integral frequency locking ring model.

Fig. 4 be Eb/N0=12dB under conditions of, using frequency deviation estimating method method of the present invention frequency locking ring frequency deviation with Track curve graph.

Fig. 5 is the structure chart of non-data aided frequency deviation estimation device embodiment of the present invention.

Fig. 6 is the structure chart of non-data aided frequency deviation estimation device preferred embodiment of the present invention.

Specific embodiment

Below in conjunction with the attached drawing in the embodiment of the present application, technical solutions in the embodiments of the present application carries out clear, complete Site preparation description, it is clear that described embodiments are only a part of embodiments of the present application, instead of all the embodiments.

If the instantaneous frequency deviation at k moment is Δ f_k, reception signal be z (k), k >=0, using the characteristic of QPSK modulation constellation, not Know that symbol only has 4 kinds of results after carrying out difference:OrWherein n' is noise.

Differentiated symbol is made decisions, differential code is estimated, i.e., extracts auxiliary information from reception symbol itself.

As shown in Figure 1, being the frame format figure of continuous communiction.

As shown in Fig. 2, for a kind of method flow of specific embodiment of the present invention:

The specific example of the method for the invention is as follows:

The first step, if modulating mode is high order modulation, such as 8PSK, 16APSK etc., then symbol will be received by, which needing, carries out QPSK Constellation transformation:

Z'(k)=| z (k) | e^{j∠z(k)·Q+jβ}

Wherein, | z (k) | long for the mould of z (k), ∠ z (k) is the phase of z (k).

If modulating mode is not high order modulation, it is directly entered in next step.

Second step initialized the reception symbol at a upper moment.

Z'(-1)=0.

The moment was received symbol and the reception symbol at upper moment progress difference operation, obtains difference by third step Signal:

Diff (k)=z'(k) [z'(k-1)]^*。

4th step adjudicates the resulting reception differential code of third step, as local differential code:

5th step removes the resulting local differential code reception differential code resulting to third step of the 4th step processing Modulated signal is gone in modulation, acquisition:

Dem (k)=diff (k) dec^*(k)。

6th step, it is resulting to the processing of the 5th step that modulation differential code is gone to carry out phase extraction.The phase is instantaneous frequency Phase caused by inclined error:

Δ θ=Im { dem (k) }.

7th step calculates instantaneous frequency deviation:

It is illustrated in figure 3 second-order proportional-plus-integral frequency locking ring model.Under conditions of Eb/N0=12dB, using the present embodiment Method complete estimation after, obtain the frequency offset tracking curve graph of frequency locking ring as shown in Figure 4.

It is illustrated in figure 5, the present invention provides a kind of embodiment of non-data aided frequency deviation estimation device.

If the instantaneous frequency deviation at k moment is Δ f_k, k >=0.

Device includes:

The reception symbol and the reception symbol of last moment at current time are carried out difference processing by difference block, and it is poor to obtain Sub-signal；The difference processing, using formula diff (k)=z'(k) [z'(k-1)]^*；

Judging module obtains judgement differential code and as local poor for making decisions processing to the differential signal Divide symbol；The decision process, using formula

Modulation module is removed, for the local differential code and the differential signal to be carried out modulation treatment, is gone Modulated signal；It is described to go modulation treatment, using formula dem (k)=diff (k) dec^*(k)；

Phase extraction module, for going modulated signal to carry out phase extraction to described, caused by obtaining instantaneous frequency deviation error Phase；The phase extraction, using formula Δ θ=Im { dem (k) }；

Frequency offset calculation module, for according to the phase calculation instantaneous frequency deviation.The calculating instantaneous frequency deviation, using formula

It is illustrated in figure 6, the preferred embodiment of non-data aided frequency deviation estimation device embodiment shown in fig. 5, at it On the basis of, further include having:

Judgment module, for judging the modulating mode for receiving symbol；

Conversion module, for carrying out QPSK constellation to the reception symbol for being judged as high order modulation by the judgment module Transformation.

Constellation transformation, using formula z'(k)=| z (k) | e^{j∠z(k)·Q+jβ}, wherein | z (k) | it is the mould of z (k) Long, ∠ z (k) is the phase of z (k), and z (k) is to receive symbol.

Initialization module initialized, z'(-1 for the reception symbol to a upper moment)=0.

Under conditions of Eb/N0=12dB, device through this embodiment be may be implemented to second order ratio as shown in Figure 3 The frequency offset tracking estimation of example integral frequency locking ring, obtains the frequency offset tracking curve graph of frequency locking ring as shown in Figure 4.It can be seen that During frequency deviation persistently changes, tracking effect is obvious after convergence for the ring.