CN103728632A - Satellite data capture device and capture method - Google Patents

Abstract

The invention relates to a satellite data capture device and a capture method. The satellite data capture device comprises a preprocessing unit, a storage unit, a parallel accumulation unit, an accumulation result storing and outputting unit, a quick Fourier transform unit, a maximum value detection unit and a judgment unit. The satellite data capture device and the capture method are compatible with various modulation modes, various systems, various code rates and code lengths, operational speed is high, and hardware resources can be saved.

Description

Satellite data acquisition equipment and catching method

Technical field

The present invention relates to a kind of data communication technology, particularly a kind of satellite data acquisition equipment and catching method.

Background technology

The covering that China's triones navigation system has been realized Asia-Pacific regional, has realized the navigation of regional.Due to adding of Chinese dipper system and European Galileo navigational system, the domain of GPS (Global Position System), by the GPS of the U.S. and the situation of Russian GLONASS two powers governance, develops into the situation of multisystem multifrequency point multi-signal system compatibility.Adding of new system and signal, will certainly cause GPS (Global Position System) of new generation (GNSS, Global Navigation Satellite System) receiver need to use the catching method of more general compatible multisystem.

Summary of the invention

Provide hereinafter about brief overview of the present invention, to the basic comprehension about some aspect of the present invention is provided.Should be appreciated that this general introduction is not about exhaustive general introduction of the present invention.It is not that intention is determined key of the present invention or pith, and nor is it intended to limit the scope of the present invention.Its object is only that the form of simplifying provides some concept, using this as the preorder in greater detail of discussing after a while.

A fundamental purpose of the present invention is to provide a kind of satellite data acquisition equipment and catching method, compatible Different Modulations, for example two-phase PSK (Binary Phase Shift Keying, BPSK) modulation, quarternary phase-shift keying (QPSK) signal (Quadrature Phase Shift Keying, QPSK) modulation, scale-of-two offset carrier (Binary Offset Carrier, BOC, multiple systems (GPS, GLONASS, the Big Dipper 2, Galileo), multiple bit rate and code length.

According to an aspect of the present invention, a kind of satellite data acquisition equipment, comprising:

Pretreatment unit, for the digital signal of catching is carried out to pre-service, obtains the first quantized signal and the second quantized signal;

Storage unit, for described the first quantized signal being stored as to the first quantized sequences output, is stored as the second quantized sequences output by described the second quantized signal, and pseudo-code is stored as to pseudo-code sequence output;

Parallel cumulative unit, for described first quantized sequences of described storage unit output and the described pseudo-code sequence of described storage unit output being carried out to the cumulative first cumulative sequence that obtains after XOR, and described second quantized sequences of described storage unit output and described pseudo-code sequence are carried out adding up after XOR obtain second sequence that adds up;

Accumulation result storage output unit, for storing and export the described first cumulative sequence and the described second cumulative sequence;

Fast Fourier Transform (FFT) unit, for using the predetermined N position by the described first cumulative sequence respectively as real part, by the predetermined N position of the described second cumulative sequence, as the plural number of imaginary part, carry out Fast Fourier Transform (FFT) respectively and obtain N complex values;

Maximum detection unit, searches for a described N complex values is carried out to maximal value, obtains power maximal value, corresponding frequency component and pseudo-code phase;

And,

Decision unit, compares for power maximal value and preset value that described maximum detection unit is detected, when the ratio of the two is greater than threshold value, with the corresponding signal capture success of pseudo-code.

According to a second aspect of the invention, a kind of satellite data catching method, is characterized in that, comprising:

The digital signal of catching is carried out to pre-service, obtain the first quantized signal and the second quantized signal;

Described the first quantized signal is stored as to the first quantized sequences output, described the second quantized signal is stored as to the second quantized sequences output, and pseudo-code is stored as to pseudo-code sequence output;

Described the first quantized sequences and described pseudo-code sequence are carried out to the cumulative first cumulative sequence that obtains after XOR, and will described the second quantized sequences carry out adding up after XOR with described pseudo-code sequence and obtain second sequence that adds up;

Store and export the described first cumulative sequence and the described second cumulative sequence;

Predetermined N position by the described first cumulative sequence, respectively as real part, is carried out to Fast Fourier Transform (FFT) as the plural number of imaginary part respectively by the predetermined N position of the described second cumulative sequence and obtained N complex values;

A described N complex values is carried out to maximal value and search, obtain power maximal value, corresponding frequency component and pseudo-code phase;

And,

Described power maximal value and preset value are compared, when the ratio of the two is greater than threshold value, with the corresponding signal capture success of pseudo-code.

Adopt satellite signal acquisition device of the present invention and catching method, compatible Different Modulations (BPSK, QPSK, BOC), multiple systems (GPS, GLONASS, the Big Dipper 2, Galileo), multiple bit rate and code length, and operation efficiency is high, has significantly saved hardware resource.

Accompanying drawing explanation

Below with reference to the accompanying drawings illustrate embodiments of the invention, can understand more easily above and other objects, features and advantages of the present invention.Parts in accompanying drawing are just in order to illustrate principle of the present invention.In the accompanying drawings, same or similar technical characterictic or parts will adopt same or similar Reference numeral to represent.

Fig. 1 is the structural drawing of a kind of embodiment of satellite signal acquisition device of the present invention;

Fig. 2 is the structural drawing of a kind of embodiment of the pretreatment unit in Fig. 1;

Fig. 3 is the schematic diagram of the data model storage of the storage unit in Fig. 1;

Fig. 4 is the schematic diagram of the pseudo-code memory module of the storage unit in Fig. 1;

Fig. 5, Fig. 6 are the parallel cumulative schematic diagram of the parallel cumulative unit in Fig. 1;

Fig. 7 is the process flow diagram of a kind of embodiment of satellite signal tracking method of the present invention.

Embodiment

Embodiments of the invention are described with reference to the accompanying drawings.The element of describing in an accompanying drawing of the present invention or a kind of embodiment and feature can combine with element and feature shown in one or more other accompanying drawing or embodiment.It should be noted that for purposes of clarity, in accompanying drawing and explanation, omitted expression and the description of unrelated to the invention, parts known to persons of ordinary skill in the art and processing.

Shown in Figure 1, be the structural drawing of a kind of embodiment of satellite data acquisition equipment of the present invention.

In the present embodiment, satellite data acquisition equipment comprises pretreatment unit 10, storage unit 20, parallel cumulative unit 30, accumulation result storage output unit 40, Fast Fourier Transform (FFT) unit 50, maximum detection unit 60 and decision unit 70.

Wherein, pretreatment unit 10, for the digital signal of catching is carried out to pre-service, obtains the first quantized signal and the second quantized signal.

Storage unit 20, for the first quantized signal being stored as to the first quantized sequences output, is stored as the second quantized sequences output by the second quantized signal, and pseudo-code is stored as to pseudo-code sequence output;

Parallel cumulative unit 30 is for the first quantized sequences of storage unit output and the pseudo-code sequence of storage unit output being carried out to the cumulative first cumulative sequence that obtains after XOR, and the second quantized sequences of storage unit output and pseudo-code sequence are carried out adding up after XOR obtains second sequence that adds up.

Accumulation result storage output unit 40 is for storing and export the first cumulative sequence and the second cumulative sequence.

Fast Fourier Transform (FFT) unit 50 for using the predetermined N position by the first cumulative sequence respectively as real part, by the predetermined N position of the second cumulative sequence, as the plural number of imaginary part, carry out Fast Fourier Transform (FFT) respectively and obtain N1 complex values, wherein N is less than or equal to N1.

Maximum detection unit 60 is for calculating quadratic sum to the N1 of identical pseudo-code phase plural number, again to the value of same frequency component wherein carry out M time cumulative, and accumulation result is carried out to maximal value and search, obtain power maximal value, corresponding frequency component and pseudo-code phase.

Decision unit 70 compares for power maximal value and preset value that maximum detection unit 60 is detected, when the ratio of the two is greater than threshold value, with the corresponding signal capture success of pseudo-code.

Shown in Figure 2, be the structural drawing of a kind of embodiment of pretreatment unit 10.

In the present embodiment, pretreatment unit comprises numerical frequency synthesis module 11, the first re-quantization module 12 and the second re-quantization module 13.

Wherein, numerical frequency synthesis module 11 is near the mutually orthogonal signal of zero-frequency for the digital signal processing of catching being become to the first preprocessed signal and the second preprocessed signal, the first preprocessed signal and the second preprocessed signal.

The first re-quantization module 12 is for the first preprocessed signal re-quantization is become to the first quantized signal, and the second re-quantization module 13 is for becoming the second quantized signal by the second preprocessed signal re-quantization.

As a kind of embodiment, the first re-quantization module 12 can comprise the first multiplier 121, the one FIR wave filter 122, the first abstraction modules 123 and the first quantization modules 124.

The first multiplier 121 is for multiplying each other the digital signal of catching and the first preprocessed signal to obtain near the first mixed signal data_mi zero-frequency, the one FIR wave filter 122 obtains the first filtering signal data_fi for the first mixed signal data_mi is carried out to filtering, the first abstraction module 123 obtains the first extraction signal data_di for the first filtering signal is extracted, thereby reduce the processing speed of signal, the first quantization modules 124 is for becoming the first quantized signal di1 by the first extraction signal quantization, ..., dim.

Similarly, the second re-quantization module 13 can comprise the second multiplier 131, the second wave filter 132, the second abstraction modules 133 and the second quantization modules 134.

The second multiplier 131 is for multiplying each other the digital signal of catching and the second preprocessed signal to obtain the second mixed signal, the 2nd FIR wave filter 132 obtains the second filtering signal for the second mixed signal is carried out to filtering, the second abstraction module 133 obtains the second extraction signal for the second filtering signal is extracted, thereby the processing speed that reduces signal, the second quantization modules 134 is for becoming the second quantized signal by the second extraction signal quantization.

Numerical frequency synthesis module 11 carries out pre-service to the digital signal adc catching, then multiplies each other with the digital signal of catching respectively, obtains zero-frequency neighbouring digital signal data_mi and data_mq.Data_mi and data_mq obtain data_fi and data_fq respectively after a FIR wave filter 122 and the 2nd FIR wave filter 132 processing, after the first abstraction module 123 and the second abstraction module 133 extractions, obtain data_di and data_dq respectively again, the object of extraction is mainly to reduce the processing speed of digital signal.

Next, the first quantization modules 124 to data_di re-quantization obtain " di1 ...; dim ", the second quantization modules 134 to data_dq re-quantization obtain " dq1 ...; dqm ", wherein dim and dqm are the numbers of a 1bit, can only be expressed as " 0 " and " 1 ".

The one FIR wave filter 122 and the 2nd FIR wave filter 132 possess the wide parameter of multi-group, select according to specific circumstances different parameters.

Here should be noted that the realization of re-quantization and the meaning of the rear data of quantification.The digital signal of catching is generally two quantifications, be quantized into+-1 and+-3, table 1-1 provided related content.

Take data_di as example, utilize formula (1.1) that the realization of re-quantization is described.

The average of supposing data_di is V ₀, variance is σ, re-quantization is data_ti.Data_ti be re-quantized to " di1 ..., dim ", " di1 ..., dim " corresponding weights be " A1 ..., Am ", (1.2) have provided mathematic(al) representation.Data_ti is quantized into+-1 and+-3, represent with 2bit, specific implementation is in Table 1-2., for quickening progress, in the time of realization, only having used 1bit now, data_ti is quantized into+and-1, " 0 " and " 1 " represents-1 and+1 respectively.

$\mathrm{data}\_\mathrm{ti}=\begin{array}{cc}+3& \mathrm{data}\_\mathrm{di}\&GreaterEqual;\mathrm{\&sigma;}+V_0;\\ +1& \mathrm{\&sigma;}+V_0>\mathrm{data}\_\mathrm{di}\&GreaterEqual;V_0;\\ -1& V_0>\mathrm{data}\_\mathrm{di}\&GreaterEqual;-\mathrm{\&sigma;}+V_0;\\ -3& \mathrm{data}\_\mathrm{di}<-\mathrm{\&sigma;}+V_0;\end{array}---\left(0.1\right)$

$\underset{n=1}{\overset{m}{\mathrm{\&Sigma;}}}(2*\mathrm{din}-1)*\mathrm{An}=\mathrm{data}\_\mathrm{ti}---\left(0.2\right)$

Signal indication during table 1-12bit ADC input

Table 1-2 re-quantization example

data_ti	A1	A2	di1	di2
					+1	1	2	0	1
-1	1	2	1	0
					+3	1	2	1	1
-3	1	2	0	0

Through pretreatment unit 10 the first quantized signal di1 after treatment ..., dim and the second quantized signal dq1 ..., dqm enters storage unit 20 and stores.

Because pre-service has been done re-quantization by data, can be in the situation that performance loss be less, storage data still less, save storage resources and calculation resources below.

Storage unit 20 is in chronological sequence sequentially spliced into the first quantized signal the first quantized sequences the output of 62.Storage unit 20 is also in chronological sequence sequentially spliced into the second quantized signal the second quantized sequences the output of 62.

As shown in Figure 3, storage unit 20 is spliced into the first quantized signal and the second quantized signal respectively data Di (n) and the Dq (n) of 62bit according to time order and function order.Suppose that di0 (0) is the first number of I branch road input, di0 (k-1) is k number; Di (n, j) represents j the numerical value that bit is corresponding in Di (n).The value of Di (1,61) storage is di0 (0) so, and Di (1,0) is di0 (61).There is following relation in Di (n, j) and di0 (k) so:

Di(n,j)=di0(n*62-j-1) (0.3)

In like manner Dq (n, j) and dq0 (k) meet:

Dq(n,j)=dq0(n*62-j-1) (0.4)

Seemingly, storage unit 20 is spliced into pseudo-code pseudo-code sequence the output of 31 according to time order and function order for the storage of pseudo-code and the storage class of data.

Shown in Figure 4, pseudo-code p is in chronological sequence spliced into the data P (n) of 31bit.Suppose that p (0) is the first number of pseudo-code, p (k-1) is k number; P (n, j) represents j the numerical value that bit is corresponding in P (n).Have:

P(n,j)=p(n*31-j-1) (0.5)

Based on the parallel cumulative mathematical derivation of XOR

Suppose that X1 and Y1 are the numbers of a 1bit, its numerical value is 0 or 1.Table 1-3 has provided

time truth table, when X1 is identical with Y1 while carrying out XOR as can be seen from the table, export 0, when different, export 1.

Table 1-3 truth table

A1 and B1 are the signed numbers of a 2bit, and its numerical value is-1 or 1.Truth table when table 1-4 has provided A1 × B1, exports 1 when X1 is identical with Y1 while carrying out phase multiplication as can be seen from the table, output-1 when different.

The truth table of table 1-4A1 × B1

Xn and An, Yn and Bn possess following relation:

An=2×Xn-1 (0.6)

Bn＝2×Yn-1 (0.7)

Suppose ordered series of numbers X1 ...., Xn and ordered series of numbers Y1 ...., in Yn, the number of same index has L numerical value identical, has:

$Z=\underset{n=1}{\overset{N}{\mathrm{\&Sigma;}}}\mathrm{Xn}\&CirclePlus;\mathrm{Yn}=N-L---\left(0.8\right)$

So corresponding ordered series of numbers A1 ...., An and ordered series of numbers B1 ...., in Bn, the number of same index has L numerical value identical, and N-L is different, has:

$C=\underset{n=1}{\overset{N}{\mathrm{\&Sigma;}}}\mathrm{An}\&CirclePlus;\mathrm{Bn}=L-(N-L)=2L-N---\left(0.9\right)$

By (0.8) and (0.9), can be drawn:

C=N-2Z (0.10)

Shown in Fig. 5, Fig. 6, the parallel cumulative schematic diagram of parallel cumulative unit 30.

In one embodiment, by the first quantized sequences and the pseudo-code sequence cumulative first cumulative sequence that obtains that walks abreast, the cumulative second cumulative sequence that obtains that simultaneously the second quantized sequences and pseudo-code sequence walked abreast, can realize 2046(62*33) point parallel cumulative.

Parallel adding up has two kinds of result output modes, can select according to the characteristic of the digital signal of catching.By parallel computation result Si2 (m, n, 1) out ..., Si2 (m, n, 11) serial output (Fig. 5), another kind be 2046 of directly outputs result Si3 (m, n) (Fig. 6).

The sequence that adds up through parallel cumulative unit 30 after treatment first and the second cumulative sequence are input to accumulation result storage unit 40 and store.

Parallel cumulative unit 30 is realized in programmable gate array (Field-Programmable Gate Array, FPGA) at the scene.The parallel cumulative characteristic that can make full use of FPGA, and then save hardware resource.

In one embodiment, accumulation result storage output unit 40 can comprise two groups of two RAM storeies, for the ping-pong operation of respectively the first cumulative sequence and the second cumulative sequence being stored and being exported.

For example, the first cumulative sequence deposits first pair of RAM storer in.Each two RAM storer comprises two groups of RAM storeies.First the first cumulative sequence deposits a RAM storer in, when first group be filled with after, corresponding data deposit second group of RAM storer in, start reading first group of data simultaneously.After second group of RAM storer has been filled with, data bank switching, to first group of RAM storer, starts reading second group of data simultaneously.

Adopt ping-pong operation, can make full use of storage space, thereby can save the storage resources in hardware.

Fast Fourier Transform (FFT) unit 50 using the predetermined N position of the first cumulative sequence of being exported by accumulation result storage output unit 40 respectively as real part, the predetermined N position of the second cumulative sequence of being exported by accumulation result storage output unit 40 is carried out Fast Fourier Transform (FFT) as the plural number of imaginary part respectively and is obtained N1 complex values, be spectrum value, wherein N is less than or equal to N1.

The N1 that maximum detection unit 60 is exported Fast Fourier Transform (FFT) unit 50 complex values is calculated quadratic sum (coherent integration) to the N1 of identical pseudo-code phase plural number, again the value of same frequency component is wherein carried out to cumulative (non-coherent integration) M time, and accumulation result is carried out to maximal value and search, obtain power maximal value, corresponding frequency component and pseudo-code phase.Characteristic and the real needs of the signal that the default weighting coefficient of choosing when the preset times (M) of choosing while wherein, carrying out non-coherent integration and non-coherent integration is caught as required arrange.

In one embodiment, maximum detection unit 60 is made comparisons to the accumulation result of the N after non-coherent integration, obtains the i time power maximal value Pmax_i and corresponding frequency component fre_i.

Maximum detection unit 60 is obtained Pmax_i and the corresponding frequency component fre_i in one-period, finally obtains one-period and mates relevant power maximal value Pmax, corresponding frequency component fre and corresponding pseudo-code phase Paddr.

Finally, power maximal value Pmax and preset value that decision unit 70 detects maximum detection unit 60 compare, when the ratio of the two is greater than threshold value, with the corresponding signal capture success of pseudo-code.Decision unit 70 for example can be arranged in DSP.

For example, first utilize a non-existent pseudo-code, after pretreatment unit 10, storage unit 20, parallel cumulative unit 30, accumulation result storage output unit 40, Fast Fourier Transform (FFT) unit 50 and maximum detection unit 60 are processed, obtain maximal value Pmax, be made as Pmax0.Then, the lock-on signal corresponding with the pseudo-code of needs caught, obtain maximal value Pmax, be made as Pmax1.When Pmax1/Pmax0 is greater than default threshold value R, thinks acquisition success, otherwise think failure.

Shown in Figure 7, be a kind of embodiment of satellite data catching method of the present invention.

In the present embodiment, satellite data catching method comprises:

S10: the digital signal of catching is carried out to pre-service, obtain the first quantized signal and the second quantized signal;

S20: the first quantized signal is stored as to the first quantized sequences output, the second quantized signal is stored as to the second quantized sequences output, and pseudo-code is stored as to pseudo-code sequence output;

S30: the first quantized sequences and pseudo-code sequence are carried out to the cumulative first cumulative sequence that obtains after XOR, and the second quantized sequences and pseudo-code sequence are carried out to cumulative second sequence that adds up that obtains after XOR;

S40: store and export the first cumulative sequence and the second cumulative sequence;

S50: the predetermined N position by the first cumulative sequence, respectively as real part, is carried out to Fast Fourier Transform (FFT) as the plural number of imaginary part respectively by the predetermined N position of the second cumulative sequence and obtained N1 complex values, and wherein N is less than or equal to N1;

S60: the N1 of identical pseudo-code phase plural number calculated to quadratic sum (coherent integration), again the value of same frequency component is wherein carried out to cumulative (non-coherent integration) M time, and accumulation result is carried out to maximal value and search, obtain power maximal value, corresponding frequency component and pseudo-code phase.Characteristic and the real needs of the signal that the default weighting coefficient of choosing when the preset times (M) of choosing while wherein, carrying out non-coherent integration and non-coherent integration is caught as required arrange.

And,

S70: power maximal value and preset value are compared, when the ratio of the two is greater than threshold value, with the corresponding signal capture success of pseudo-code.

In S70, for example choosing of preset value can be carried out in accordance with the following methods:

For example, first utilize one to receive and in signal, do not exist but the identical pseudo-code of characteristic, after pretreatment unit 10, storage unit 20, parallel cumulative unit 30, accumulation result storage output unit 40, Fast Fourier Transform (FFT) unit 50 and maximum detection unit 60 are processed, obtain maximal value Pmax, be made as Pmax0.Then, the lock-on signal corresponding with the pseudo-code of needs caught, obtain maximal value Pmax, be made as Pmax1.When Pmax1/Pmax0 is greater than default threshold value R, thinks acquisition success, otherwise think failure.

In one embodiment, step S10 can specifically comprise:

S11: the digital signal processing of catching is become to the first preprocessed signal and the second preprocessed signal, and the first preprocessed signal and the second preprocessed signal are near mutually orthogonal signal zero-frequency;

S12: the first preprocessed signal re-quantization is become to the first quantized signal;

And,

S13: the second preprocessed signal re-quantization is become to the second quantized signal.

Step S12 can specifically comprise:

The digital signal of catching and the first preprocessed signal are multiplied each other and obtain the first mixed signal, the first mixed signal is carried out to filtering and obtain the first filtering signal, the first filtering signal is extracted and obtains the first extraction signal, the first extraction signal quantization is become to the first quantized signal.

Step S13 can specifically comprise:

The digital signal of catching and the second preprocessed signal are multiplied each other and obtain the second mixed signal, the second mixed signal is carried out to filtering and obtain the second filtering signal, the second filtering signal is extracted and obtains the second extraction signal, the second extraction signal quantization is become to the second quantized signal.

In one embodiment, step S20 can specifically comprise:

The first quantized signal is in chronological sequence sequentially spliced into the first quantized sequences the output of 62;

The second quantized signal is in chronological sequence sequentially spliced into the second quantized sequences the output of 62;

And,

Pseudo-code is spliced into pseudo-code sequence the output of 31 according to time order and function order.

In one embodiment, step S30 can also comprise:

According to the characteristic of the digital signal of catching, select the described first cumulative sequence and the second cumulative sequence series output or parallel output.

In one embodiment, step S40 can specifically comprise:

The ping-pong operation of respectively the first cumulative sequence and the second cumulative sequence being stored and being exported.

Adopt satellite data acquisition equipment of the present invention and catching method, compatible Different Modulations (BPSK, QPSK, BOC), multiple systems (GPS, GLONASS, the Big Dipper 2, Galileo), multiple bit rate and code length, and arithmetic speed is higher, and can save hardware resource.

Above some embodiments of the present invention are described in detail.As one of ordinary skill in the art can be understood, whole or any steps or the parts of method and apparatus of the present invention, can be in the network of any computing equipment (comprising processor, storage medium etc.) or computing equipment, with hardware, firmware, software or their combination, realized, this is that those of ordinary skills use their basic programming skill just can realize in the situation that understanding content of the present invention, therefore need not illustrate at this.

In addition, it is evident that, when relating to possible peripheral operation in superincumbent explanation, will use undoubtedly any display device and any input equipment, corresponding interface and the control program that are connected with any computing equipment.Generally speaking, related hardware, software in computing machine, computer system or computer network and realize hardware, firmware, software or their combination of the various operations in preceding method of the present invention, forms equipment of the present invention and each building block thereof.

Therefore,, based on above-mentioned understanding, object of the present invention can also realize by move a program or batch processing on any messaging device.Described messaging device can be known common apparatus.Therefore, object of the present invention also can be only by providing the program product that comprises the program code of realizing described method or equipment to realize.That is to say, such program product also forms the present invention, and storage or the medium that transmits such program product also form the present invention.Obviously, described storage or transmission medium can be well known by persons skilled in the art, or storage or the transmission medium of any type developing in the future, therefore also there is no need at this, various storages or transmission medium to be enumerated.

In equipment of the present invention and method, obviously, each parts or each step reconfigure after can decomposing, combine and/or decomposing.These decomposition and/or reconfigure and should be considered as equivalents of the present invention.The step that also it is pointed out that the above-mentioned series of processes of execution can order naturally following the instructions be carried out in chronological order, but does not need necessarily according to time sequencing, to carry out.Some step can walk abreast or carry out independently of one another.Simultaneously, in the above in the description of the specific embodiment of the invention, for a kind of embodiment, describe and/or the feature that illustrates can be used in same or similar mode in one or more other embodiment, combined with the feature in other embodiment, or substitute the feature in other embodiment.

Should emphasize, term " comprises/comprises " existence that refers to feature, key element, step or assembly while using herein, but does not get rid of the existence of one or more further feature, key element, step or assembly or add.

Although described the present invention and advantage thereof in detail, be to be understood that in the case of not exceeding the spirit and scope of the present invention that limited by appended claim and can carry out various changes, alternative and conversion.And scope of the present invention is not limited only to the specific embodiment of the described process of instructions, equipment, means, method and step.One of ordinary skilled in the art will readily appreciate that from disclosure of the present invention, can use carry out with the essentially identical function of corresponding embodiment described herein or obtain process, equipment, means, method or step result essentially identical with it, that existing and will be developed future according to the present invention.Therefore, appended claim is intended to comprise such process, equipment, means, method or step in their scope.

Claims (12)

1. a satellite data acquisition equipment, is characterized in that, comprising:

Pretreatment unit, for the digital signal of catching is carried out to pre-service, obtains the first quantized signal and the second quantized signal;

Storage unit, for described the first quantized signal being stored as to the first quantized sequences output, is stored as the second quantized sequences output by described the second quantized signal, and pseudo-code is stored as to pseudo-code sequence output;

Parallel cumulative unit, for described first quantized sequences of described storage unit output and the described pseudo-code sequence of described storage unit output being carried out to the cumulative first cumulative sequence that obtains after XOR, and described second quantized sequences of described storage unit output and described pseudo-code sequence are carried out adding up after XOR obtain second sequence that adds up;

Accumulation result storage output unit, for storing and export the described first cumulative sequence and the described second cumulative sequence;

Fast Fourier Transform (FFT) unit, be used for the predetermined N number by the described first cumulative sequence respectively as real part, by the predetermined N number of the described second cumulative sequence, carry out Fast Fourier Transform (FFT) respectively as the plural number of imaginary part and obtain N1 complex values, wherein N is less than or equal to N1;

Maximum detection unit, for the N1 of identical pseudo-code phase plural number calculated to quadratic sum, then to the value of same frequency component wherein carry out M time cumulative, and accumulation result is carried out to maximal value and searches, obtain power maximal value, frequency component and pseudo-code phase accordingly;

And,

Decision unit, compares for power maximal value and preset value that described maximum detection unit is detected, when the ratio of the two is greater than threshold value, with the corresponding signal capture success of pseudo-code.

2. satellite data acquisition equipment according to claim 1, is characterized in that, described pretreatment unit comprises:

Numerical frequency synthesis module, for described digital signal processing of catching is become to the first preprocessed signal and the second preprocessed signal, described the first preprocessed signal and described the second preprocessed signal are near mutually orthogonal signal zero-frequency;

The first re-quantization module, for becoming the first quantized signal by described the first preprocessed signal re-quantization;

And,

The second re-quantization module, for becoming the second quantized signal by described the second preprocessed signal re-quantization.

3. satellite data acquisition equipment according to claim 2, is characterized in that:

Described the first re-quantization module comprises the first multiplier, a FIR wave filter, the first abstraction module and the first quantization modules;

Described the first multiplier is for multiplying each other described digital signal of catching and described the first preprocessed signal to obtain the first mixed signal, a described FIR wave filter obtains the first filtering signal for described the first mixed signal is carried out to filtering, described the first abstraction module is for the first filtering signal is extracted and obtains the first extraction signal, and described the first quantization modules becomes the first quantized signal for extracting signal quantization by described first;

Described the second re-quantization module comprises the second multiplier, the second wave filter, the second abstraction module and the second quantization modules;

Described the second multiplier is for multiplying each other described digital signal of catching and described the second preprocessed signal to obtain the second mixed signal, described the 2nd FIR wave filter obtains the second filtering signal for described the second mixed signal is carried out to filtering, described the second abstraction module is for the second filtering signal is extracted and obtains the second extraction signal, and described the second quantization modules becomes the second quantized signal for extracting signal quantization by described second.

4. satellite data acquisition equipment according to claim 1, is characterized in that:

Described storage unit is for being in chronological sequence sequentially spliced into described the first quantized signal the first quantized sequences the output of 62;

Described storage unit is for being in chronological sequence sequentially spliced into described the second quantized signal the second quantized sequences the output of 62;

Described storage unit is also for being spliced into described pseudo-code pseudo-code sequence the output of 31 according to time order and function order.

5. satellite data acquisition equipment according to claim 1, is characterized in that:

The characteristic of the digital signal of catching described in described parallel cumulative unit basis is selected the described first cumulative sequence and the second cumulative sequence series output or parallel output.

6. satellite data acquisition equipment according to claim 1, is characterized in that:

Described accumulation result storage output unit comprises two groups of two RAM storeies, for the ping-pong operation of respectively the first cumulative sequence and the second cumulative sequence being stored and being exported.

7. a satellite data catching method, is characterized in that, comprising:

The digital signal of catching is carried out to pre-service, obtain the first quantized signal and the second quantized signal;

Described the first quantized signal is stored as to the first quantized sequences output, described the second quantized signal is stored as to the second quantized sequences output, and pseudo-code is stored as to pseudo-code sequence output;

Described the first quantized sequences and described pseudo-code sequence are carried out to the cumulative first cumulative sequence that obtains after XOR, and will described the second quantized sequences carry out adding up after XOR with described pseudo-code sequence and obtain second sequence that adds up;

Store and export the described first cumulative sequence and the described second cumulative sequence;

Predetermined N number by the described first cumulative sequence, respectively as real part, is carried out to Fast Fourier Transform (FFT) as the plural number of imaginary part respectively by the predetermined N number of the described second cumulative sequence and obtained N1 complex values;

The N1 of identical pseudo-code phase plural number calculated to quadratic sum, then to the value of same frequency component wherein carry out M time cumulative, and accumulation result is carried out to maximal value and searches, obtain power maximal value, frequency component and pseudo-code phase accordingly;

And,

Described power maximal value and preset value are compared, when the ratio of the two is greater than threshold value, with the corresponding signal capture success of pseudo-code.

8. satellite data catching method according to claim 7, is characterized in that, described " digital signal of catching is carried out to pre-service, obtain the first quantized signal and the second quantized signal " specifically comprises:

Described digital signal processing of catching is become to the first preprocessed signal and the second preprocessed signal, and described the first preprocessed signal and described the second preprocessed signal are near mutually orthogonal signal zero-frequency;

Described the first preprocessed signal re-quantization is become to the first quantized signal;

And,

Described the second preprocessed signal re-quantization is become to the second quantized signal.

9. satellite data catching method according to claim 8, is characterized in that:

Described " described the first preprocessed signal re-quantization is called to the first quantized signal " specifically comprises:

Described digital signal of catching and described the first preprocessed signal are multiplied each other and obtain the first mixed signal, described the first mixed signal is carried out to filtering and obtain the first filtering signal, the first filtering signal is extracted and obtains the first extraction signal, and by described first, extracting signal quantization becomes the first quantized signal;

Described " described the second preprocessed signal re-quantization is called to the second quantized signal " specifically comprises:

Described digital signal of catching and described the second preprocessed signal are multiplied each other and obtain the second mixed signal, described the second mixed signal is carried out to filtering and obtain the second filtering signal, the second filtering signal is extracted and obtains the second extraction signal, and by described second, extracting signal quantization becomes the second quantized signal.

10. satellite data catching method according to claim 7, it is characterized in that, described " described the first quantized signal is stored as to the first quantized sequences output; described the second quantized signal is stored as to the second quantized sequences output, and pseudo-code is stored as to pseudo-code sequence output " specifically comprises:

Described the first quantized signal is in chronological sequence sequentially spliced into the first quantized sequences the output of 62;

Described the second quantized signal is in chronological sequence sequentially spliced into the second quantized sequences the output of 62;

Described pseudo-code is spliced into pseudo-code sequence the output of 31 according to time order and function order.

11. satellite data catching methods according to claim 7, it is characterized in that, described " described the first quantized sequences and described pseudo-code sequence are carried out to the cumulative first cumulative sequence that obtains after XOR; and will described the second quantized sequences carry out adding up after XOR with described pseudo-code sequence obtain second sequence that adds up " afterwards, also comprise:

According to the characteristic of described digital signal of catching, select the described first cumulative sequence and the second cumulative sequence series output or parallel output.

12. satellite data catching methods according to claim 7, is characterized in that, described " storing and export the described first cumulative sequence and the described second cumulative sequence " specifically comprises:

The ping-pong operation of respectively the first cumulative sequence and the second cumulative sequence being stored and being exported.

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