CN2660797Y - SN ratio measurer of direct sequences pread spectrum signal - Google Patents
SN ratio measurer of direct sequences pread spectrum signal Download PDFInfo
- Publication number
- CN2660797Y CN2660797Y CNU032773315U CN03277331U CN2660797Y CN 2660797 Y CN2660797 Y CN 2660797Y CN U032773315 U CNU032773315 U CN U032773315U CN 03277331 U CN03277331 U CN 03277331U CN 2660797 Y CN2660797 Y CN 2660797Y
- Authority
- CN
- China
- Prior art keywords
- signal
- input
- output
- converters
- matched filter
- 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.)
- Expired - Fee Related
Links
Images
Landscapes
- Noise Elimination (AREA)
Abstract
The utility model relates to a device for signal-to-noise ratio measurement of direct sequence spread spectrum (DSSS) received signal and existence determination of DSSS spread spectrum signal in received signal, in particular to a signal-to-noise measurement device for direct sequence spread spectrum. The utility model consists of two A/D converters (11), (12), a matched filter (13), a clock signal generator (14) and a digital signal processor (15). The input of the two A/D converters (11), (12) are respectively access to baseband simulating in-phase branch input signal I and baseband simulating quadrature branch input signal Q, the output of the two A/D converters (11), (12) are access to the input of the matches filter (13), the output of the matched filter (13) is access to the input of the digital signal processor (15), and the SNR parameter can be transported from the output of the digital signal processor (15) to finish signal-to-noise measurement; the output of the clock signal generator (14) is access to the clock input terminal of the two A/D converters (11), (12) and the synchronous signal control terminal of part of the matched filter (13) at the same time.
Description
Technical field
The utility model relates to military antijam communication device, particularly relates to the device that the existence of DSSS spread-spectrum signal in the snr measurement that is used for direct sequence spread spectrum (DSSS) received signal and the received signal is judged.
Background technology
Direct sequence spread spectrum communication is one of main means of military antijam communication.Signal of communication has that antijamming capability is strong because military communication requires, the characteristics of good confidentiality, good concealment, require communication signal emitting side to communicate with minimum transmitting power, under the precondition that guarantees reliable communication, the disguise of inhibit signal, the intercept probability of reduction signal of communication.Keeping the reference signal of best transmit power (lowest transmit power under the reliable communication prerequisite), is the signal to noise ratio (snr) parameter in the received signal.The method that SNR to received signal measures has multiple, in the time of as the transmission signal of communication, sends beacon; In information symbol, periodically insert the known symbol that is referred to as frequency pilot sign; Utilize the information bit of having adjudicated to carry out delay measurements or the like to received signal.But when sending signal of communication, launch certain known signal, as the frequency pilot sign of the tone signal of given frequency, contents known or guidance code etc., not only consume transmitting power, and destroyed the disguise of signal of communication, and reducing communication efficiency, this is unallowed in military communication.The delay measurements of decision-feedback formula requires transmitting end to send midamble code equally, and owing to there is misjudgement inevitably, makes that the SNR measurement becomes unreliable, has avalanche effect under low SNR condition.
On the other hand, SNR measures, and is the measurement of signal of communication quality, and it is different from the measurement of received signal intensity.Received signal strength measurement has only been measured the power of receiver received signal, signal quality is not measured.When signal was interfered, the measurement of signal power can not the reflected signal quality.Common SNR metering system also is subjected to the interference of various unfavorable factors easily, the influence of channel stability, the conforming influence of transmitting-receiving frequency etc.Particularly when communication terminal carrier high-speed motion, the multipath fading of the communication channel of bringing changes and Doppler (Doppler) frequency displacement variation etc.
Summary of the invention
The purpose of this utility model is exactly in order to address the above problem, a kind of snr measurement device of Direct Sequence Spread Spectrum Signal is provided, it can keep the disguise and the validity of military antijam communication signal, guarantee under low SNR condition, under the undesirable condition of channel condition,, be that the power adaptive adjustment is implemented in the DSSS spread spectrum communication to the reliable measurements of the SNR of DSSS spread spectrum received signal, keep optimal communication power, reference signal is provided.
Technical solution of the present utility model:
A kind of snr measurement device of Direct Sequence Spread Spectrum Signal, it is characterized in that it is by two A/D converters (11), (12), matched filter (13), clock-signal generator (14), digital signal processor (15) is formed, two A/D converters (11), (12) input meets baseband analog in-phase branch input signal I and baseband analog quadrature branch input signal Q respectively, their output connects the input of matched filter (13), the output of matched filter (13) connects the input of digital signal processor (15), can obtain desired SNR parameter value from the output of digital signal processor (15), finish snr measurement; The output of clock-signal generator (14) connects the input end of clock of two A/D converters (11), (12) and the synchronizing signal control end of part matched filter (13) simultaneously.
The SNR measurement mechanism of the DSSS spread spectrum received signal that the utility model proposes, do not need to know received signal particular content at a time, thereby do not need transmitting terminal to send Given information, do not destroy the original signal characteristic of signal of communication, particularly the disguise of signal acquires a special sense in the military communication field.DSSS received signal SNR measuring appliance provided by the utility model, Doppler frequency displacement and channel fading are changed insensitive, thereby guaranteed the confidence level of SNR measurement result.
Characteristics of the present utility model are:
1. be implemented in receiving terminal DSSS spread spectrum received signal is carried out the online in real time measurement;
2. provide reference signal for automated power control;
3. provide judgment basis for interference analysis;
For receiving terminal to received signal in the existence of DSSS spread-spectrum signal judge foundation be provided.
Purposes of the present utility model is:
At receiving terminal, the DSSS spread-spectrum signal is measured in real time, thereby for safe and reliable communication, power adaptive are controlled, interference analysis provides foundation and assurance.
The application conditions of the DSSS spread-spectrum signal SNR measuring appliance that the utility model patent is provided is: the receiving terminal of DSSS spread spectrum communication, realized to received signal catching and despreading, and carry out online SNR in the digital baseband after despreading to received signal and measure.
The digital baseband signal of the utility model after to despreading carries out conversion and statistics analysis, utilizes the noise statistical property different with signal of communication to carry out Mathematical Statistics Analysis, thereby the SNR that realizes received signal measures.The utility model has realized that the SNR under additional signal or the information condition measures, and this is significant to military communication, because this SNR metering system, has kept original feature of signal of communication, does not destroy the advantage of DSSS signal good concealment.
Description of drawings
Fig. 1 is a theory diagram of the present utility model.
Fig. 2 is a signal flow graph of the present utility model.
Embodiment
As Fig. 1, the snr measurement device of Direct Sequence Spread Spectrum Signal of the present utility model, it is by two A/D converters 11,12 (model that can select ADI company for use is the double A/D converter of AD9288), matched filter 13, (model that can select altera corp for use is the integrated chip of 20K200E to clock-signal generator 14, this circuit has been realized matched filter and clock generator circuit by programming, wherein clock-signal generator provides sampled clock signal to AD9288), (model that can select TI company for use is the dsp chip of TMS320C6201 to digital signal processor 15, it finishes normalized to the matched filter output signal by programming, High Order Moment is calculated, variance is calculated, SNR calculates and The disposal of gentle filter) form, two A/ D converters 11,12 input meets baseband analog in-phase branch input signal I and baseband analog quadrature branch input signal Q respectively, their output connects the input of matched filter 13, the output of matched filter 13 connects the input of digital signal processor 15, can obtain desired SNR parameter value from the output of digital signal processor 15, finish snr measurement; The output of clock-signal generator 14 connects the input end of clock of two A/ D converters 11,12 and the synchronizing signal control end of part matched filter 13 simultaneously.
The course of work of the utility model patent is: the DSSS spread-spectrum signal enters reception antenna through the transmission of channel, amplify and serial down-conversion through low noise amplifier, become the Analog Baseband orthogonal signalling, be I road analog baseband signal and Q road analog baseband signal, this two-way analog signal becomes I way word baseband signal and Q way word baseband signal after the A/D converter sample, I way word baseband signal and Q roadbed band digital baseband signal are input to input and normalized device I and input and normalized device Q in the digital signal processor respectively by matched filter, I signal through normalized is input to the I input of High Order Moment calculator and the I input of variance calculator simultaneously, be input to the Q input of High Order Moment calculator Q input and variance calculator simultaneously through the Q signal of normalized, the output of High Order Moment calculator and the output of variance calculator are input to the SNR instantaneous value that calculates received signal in the SNR calculator simultaneously, the output signal of SNR calculator is input in smothing filtering and the output circuit, the SNR instantaneous value is carried out smothing filtering, eliminate and disturb and shake, carry out the output format conversion then, output in the central processing unit of being responsible for receiver control.This two-way digital baseband signal is being input to when digital despreading demodulator carries out despread-and-demodulation, also be input to and carry out signal-to-noise ratio (SNR) estimation in the SNR estimator, so that judgment basis is provided for whether power control, despread-and-demodulation device work on, whether communication line interrupts etc.It is the basis that receiver carries out operating state control.
Signal flow of the present utility model such as Fig. 2:
Step 21: read in the digital baseband signal after the despreading;
Step 22: the digital baseband signal that reads in is carried out statistical analysis;
Step 23: judge whether statistical analysis finishes; If do not finish, then change step 21 over to and continue the input digit baseband signal; Finish if analyze, then change step 24 over to;
Step 24: calculate SNR;
Step 25: result of calculation is pressed call format conversion output.Change step 21 then over to and repeat above process.
Claims (1)
1, a kind of snr measurement device of Direct Sequence Spread Spectrum Signal, it is characterized in that it is by two A/D converters (11), (12), matched filter (13), clock-signal generator (14), digital signal processor (15) is formed, two A/D converters (11), (12) input meets baseband analog in-phase branch input signal I and baseband analog quadrature branch input signal Q respectively, their output connects the input of matched filter (13), the output of matched filter (13) connects the input of digital signal processor (15), can obtain desired SNR parameter value from the output of digital signal processor (15), finish snr measurement; The output of clock-signal generator (14) connects the input end of clock of two A/D converters (11), (12) and the synchronizing signal control end of part matched filter (13) simultaneously.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU032773315U CN2660797Y (en) | 2003-08-04 | 2003-08-04 | SN ratio measurer of direct sequences pread spectrum signal |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU032773315U CN2660797Y (en) | 2003-08-04 | 2003-08-04 | SN ratio measurer of direct sequences pread spectrum signal |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2660797Y true CN2660797Y (en) | 2004-12-01 |
Family
ID=34331785
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNU032773315U Expired - Fee Related CN2660797Y (en) | 2003-08-04 | 2003-08-04 | SN ratio measurer of direct sequences pread spectrum signal |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN2660797Y (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2797648C1 (en) * | 2022-11-29 | 2023-06-07 | Федеральное государственное бюджетное образовательное учреждение высшего образования "Казанский национальный исследовательский технический университет им. А.Н. Туполева - КАИ" | Method for improving the noise immunity of a dual-channel receiver with an additional channel based on a phase detector |
-
2003
- 2003-08-04 CN CNU032773315U patent/CN2660797Y/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2797648C1 (en) * | 2022-11-29 | 2023-06-07 | Федеральное государственное бюджетное образовательное учреждение высшего образования "Казанский национальный исследовательский технический университет им. А.Н. Туполева - КАИ" | Method for improving the noise immunity of a dual-channel receiver with an additional channel based on a phase detector |
| RU2799110C1 (en) * | 2023-04-17 | 2023-07-04 | федеральное государственное бюджетное образовательное учреждение высшего образования "Национальный исследовательский университет "МЭИ" (ФГБОУ ВО "НИУ "МЭИ") | Method for measuring signal to noise ratio of signals with angular manipulation |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Betz | Effect of partial-band interference on receiver estimation of C/N0: Theory | |
| US4597107A (en) | Modulation detector and classifier | |
| Guvenc et al. | Non-coherent TOA estimation in IR-UWB systems with different signal waveforms | |
| CN102577289B (en) | Wireless receiver | |
| CA2437399A1 (en) | Apparatus and method of velocity estimation | |
| CN101834632B (en) | Method for capturing synchronization in frequency hopping communication | |
| Noneaker et al. | On the chip rate of CDMA systems with doubly selective fading and rake reception | |
| RU2003134627A (en) | EVALUATION OF DOPPLER SPEED / SPEED IN MOBILE WIRELESS COMMUNICATION DEVICES AND METHODS FOR THIS ASSESSMENT | |
| CN110224720A (en) | A kind of CSS system non-coherent demodulation method based on multiplication cross second differnce structure | |
| US6965630B1 (en) | Mode Controller for signal acquisition and tracking in an ultra wideband communication system | |
| DE69926869D1 (en) | METHOD AND DEVICE FOR DETECTING A FREQUENCY SYNCHRONIZATION SIGNAL | |
| CN108650203B (en) | Modulation mode identification method based on reconnaissance receiver | |
| CN2660797Y (en) | SN ratio measurer of direct sequences pread spectrum signal | |
| RU2008100049A (en) | METHOD FOR ESTIMATING CORRELATIONS OF DISTORTIONS IN A WIRELESS COMMUNICATION RECEIVER AND DEVICE FOR ITS IMPLEMENTATION | |
| RU2010116189A (en) | METHOD OF SUPPRESSING INTERFERENCE IN PULSE COMMUNICATION SYSTEMS | |
| US20010033603A1 (en) | Spread spectrum burst signal receiver and related methods | |
| CN104467915B (en) | Phase noise analyzing method of incoherent ultra-wide band communication system | |
| CN100433563C (en) | Correlated receiver and signal receiving method for super-broad band radio communication system | |
| AU2002212389A1 (en) | Receiver and reception method | |
| Iinatti et al. | Differentially coherent code acquisition in Doppler | |
| KR20070047628A (en) | The low power consumption type uwb transceiver and network system using the same | |
| CN109510644A (en) | Direct-sequence spread-spectrum communication signal interference detection method based on eye figure energy | |
| CN115580317B (en) | Ultra-wideband synchronization capture method and device | |
| CN115079211B (en) | Satellite navigation signal performance evaluation method capable of being used as frequency coordination basis | |
| EP1137193A2 (en) | Method and circuit for delay profile measurement |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C19 | Lapse of patent right due to non-payment of the annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |