CN101814941A - Method for detecting deterioration degree of BER performance of BPSK satellite communication systems - Google Patents

Abstract

The invention discloses a method for detecting deterioration degree of BER (bit error rate) performance of BPSK satellite communication systems. The method comprises: calculating the BER of a BPSK satellite communication system under single-frequency interference or not under single-frequency interference respectively; calculating the amount of BER performance deterioration of the BPSK satellite communication system under single-frequency interference according to the BER of the BPSK satellite communication system under single-frequency interference or not under single-frequency interference; and comparing the amount of BER performance deterioration with a preset threshold value of the amount of BER performance deterioration and judging the BER performance to be severely deteriorative if the amount of BER performance deterioration is greater than the threshold value. Due to the invention, the prior method for detecting the BER performance deterioration of BPSK satellite communication systems under single-frequency interference is perfected and improved, and an accurate detection method with generality and practicability is provided. In addition, the method of the invention has the advantages of more rigorous analysis, more accurate and credible result and better practicability.

Description

A kind of method that detects BPSK satellite communication system error performance deterioration degree

Technical field

The present invention relates to satellite communication system error performance detection technique field, particularly relate to and a kind of binary phase shift keying (BPSK) satellite communication system is being subjected to the method that the error performance deterioration degree detects under the single-frequency disturbed condition.

Background technology

Disturbed the influence that the satellite communication system error performance that adopts the BPSK modulation system is worsened in single year, the tracking performance that is typically implemented in carrier wave worsens and two aspects of detection judgement mis-behave, under the situation of single-frequency interference strength less than signal carrier intensity, its influence is mainly reflected in and detects judgement mis-behave aspect.

Existing detection method to BPSK satellite communication system error performance deterioration degree mainly is divided three classes: the first kind is to disturb conversion for the equivalent noise component in frequency acceptance band single-frequency, then this equivalence noise component(s) is carried out check and analysis; Second class is disturbed single-frequency with receiving noise and is made a distinction, but but single-frequency is disturbed phase place to detect as the amount of determining; Though the 3rd class will disturb phase place to introduce in the check and analysis as random quantity, but only provide The qualitative analysis, do not form the detection method that quantizes.

All there is defective in various degree in above-mentioned three class methods, can directly cause testing result generation deviation even mistake occur, influence the Anti-interference Design analysis in the engineering application.At first there is theoretic leak in first kind method, error rate calculation formula when the BPSK communication system is noiseless is the statistic analysis result that obtains when the supposition system noise satisfies Gaussian Profile, after disturbing equivalence to be noise component(s) the single-frequency, system noise does not satisfy Gaussian Profile, therefore adopt original error rate calculation formula again, not rigorous in theory.Secondly, second class methods are only applicable to disturb and the constant communication system of receiving terminal distance, and signal transmission distance is changing in satellite communication system, therefore will cause the interference signal phase place constantly to change, the simple signal phase place obviously not had generality as the analytical method of determined value.At last, the 3rd class methods do not provide the detection method of quantification, do not possess practicality in engineering practice.

Defective in view of above-mentioned existing detection method, the inventor is based on experience and the gains in depth of comprehension of being engaged in development of lunar orbiting exploration project data receiving system and design, and the knowledge use of cooperation Principle of Communication and probability theory, actively studied innovation, in the hope of found a kind of accurately, have generality and practicality disturbed by single-frequency to the BPSK satellite communication system time the method that detects of error performance deterioration degree, through constantly calculation, rational analysis create the present invention finally.

Summary of the invention

(1) technical problem that will solve

In view of this, main purpose of the present invention is to provide a kind of method of the BPSK of detection satellite communication system error performance deterioration degree, to realize the accurate detection to system's error performance deterioration degree.

(2) technical scheme

For achieving the above object, the invention provides a kind of method of the BPSK of detection satellite communication system error performance deterioration degree, this method comprises:

The error rate when error rate when calculating the BPSK satellite communication system respectively and disturbed by single-frequency and the interference of no single-frequency;

The error rate when error rate when disturbed by single-frequency according to this BPSK satellite communication system and no single-frequency are disturbed, the error performance deterioration amount when calculating BPSK satellite communication system is disturbed by single-frequency;

Relatively this error performance deterioration amount and predefined error rate deterioration amount threshold value worsen if this error performance deterioration amount, is then judged error performance severe greater than this threshold value.

In the such scheme, the error rate when described calculating BPSK satellite communication system is disturbed by single-frequency comprises: with the carrier wave in the BPSK satellite communication system and noise frequency difference Δ f, bit rate R _b, channel noise power spectrum density N ₀, received signal to noise ratio E _b/ N ₀And carrier/interface ratio (A/A _i) ²The substitution formula

Error rate P when calculating BPSK satellite communication system is disturbed by single-frequency _e, wherein

Δ f ≠ 0 o'clock

Be the amplitude of BPSK modulation signal, A _iBe the amplitude of single carrier interference signal,

T=1/R _bBe symbol width, Δ f=f _c-f _iBe the difference on the frequency of carrier wave and interference signal, E _bRepresent the signal energy in each code-element period, R _bBe transmission code speed, N ₀Be the channel noise power spectrum density.

In the such scheme, the error rate when described calculating BPSK satellite communication system does not have the single-frequency interference comprises: with the system signal noise ratio E in the BPSK satellite communication system _b/ N ₀The substitution formula

Error rate P when calculating BPSK satellite communication system does not have the single-frequency interference ₀, wherein

E _bBe the signal energy in each code-element period, N ₀Be the channel noise power spectrum density.

In the such scheme, the described error rate and the error rate of no single-frequency when disturbing when disturbed by single-frequency according to this BPSK satellite communication system, the error performance deterioration amount when calculating the BPSK satellite communication system and disturbed by single-frequency comprises: the error rate P when this BPSK satellite communication system is subjected to the single-frequency interference _eError rate P when disturbing with this no single-frequency ₀Substitution formula H=lg (P _e/ P ₀), calculate the error performance deterioration amount H of BPSK satellite communication system when disturbed by single-frequency.

In the such scheme, described relatively this error performance deterioration amount and predefined error rate deterioration amount threshold value, further comprise: if this error performance deterioration amount is less than or equal to this threshold value, judge that then error performance does not have severe to worsen, need not this BPSK satellite communication system to be carried out anti-interference process at this single-frequency interference.

In the such scheme, described error performance deterioration degree can not be tolerated that this method further comprises: disturb at this single-frequency this BPSK satellite communication system is carried out anti-interference process.

(3) beneficial effect

From technique scheme as can be seen, the present invention has following beneficial effect:

1, the method for this detection BPSK satellite communication system error performance deterioration degree provided by the invention, error performance worsens the method that detects when having improved existing BPSK satellite communication system and disturbed by single-frequency, provide a kind of accurately, have a detection method of generality and practicality.

2, the method for this detection BPSK satellite communication system error performance deterioration degree provided by the invention, not simply single-frequency to be disturbed conversion to carry out check and analysis for the equivalent noise in the frequency acceptance band, but the single-frequency interference is independently considered as the part of system's received signal, and with its phase place as stochastic variable, adopt maximal possibility estimation, statistics is detecting judgement bit error probability constantly, by more noiseless and the error rate when disturbing is arranged, realized accurate detection to system's error performance deterioration degree.This methods analyst is more rigorous, and the result is more accurately credible, and has more practicality.

3, the method for this detection BPSK satellite communication system error performance deterioration degree provided by the invention, successful Application is in the lunar orbiting exploration engineering, for the Anti-interference Design of China and co-ordination of Japanese lunar exploration satellite frequency and grounded receiving station provides foundation, provide foundation to the analyzing and processing of analogue in the later deep space satellite communication.

Description of drawings

Fig. 1 is the theory analysis block diagram of detection BPSK satellite communication system error performance deterioration degree provided by the invention;

Fig. 2 is the method flow diagram of detection BPSK satellite communication system error performance deterioration degree provided by the invention.

Embodiment

For making the purpose, technical solutions and advantages of the present invention clearer, below in conjunction with specific embodiment, and with reference to accompanying drawing, the present invention is described in more detail.

At first, introduce realization principle of the present invention.The taking into account system received signal disturbs three parts to form by BPSK modulation signal, white Gaussian noise and single-frequency, and wherein BPSK modulation signal carrier amplitude and frequency, noise power spectral density, single-frequency interference magnitude and frequency are for determining amount.In addition, not only with interchannel noise as by the stochastic variable of Gaussian Profile, and single-frequency interference signal phase place carried out probability analysis as equally distributed stochastic variable unification, adopt maximal possibility estimation, statistics is detecting judgement error probability constantly, thereby obtains the error rate of system when different signal to noise ratios, interfering frequency and interference strength; Error rate when noiseless is compared with this error rate and system then, obtains the error performance deterioration amount under the current disturbed condition, for system's Anti-interference Design provides foundation.

Please refer to Fig. 1, Fig. 1 is the theory analysis block diagram of detection BPSK satellite communication system error performance deterioration degree provided by the invention.Consider to exist the situation of single-frequency interference earlier.Be without loss of generality, will send information code element and be approximately random sequence and consider.Baseband waveform is the bipolarity nonreturn to zero code; Transmission waveform s after the BPSK modulation _i(t) expression---amplitude is A, and carrier frequency is f _c, bit rate is R _bBpsk signal (symbol width T=1/R _b).

$s_i\left(t\right)=\left\{\begin{array}{c}{s}_1\left(t\right)=A\cos 2\mathrm{\π}{f}_{c}t......1_{\′\′}^{\′\′}\\ s_2\left(t\right)=-A\cos 2\mathrm{\π}{f}_{c}t....0_{\′\′}^{\′\′}\end{array}\right.---\left(1\right)$

Wherein

E _bRepresent s in each code-element period _i(t) energy.

It is A that interference signal is expressed as amplitude _i, frequency is f _iSingle-carrier signal (f _iIn system's band is logical), represent with I (t):

Wherein

Be in (0,2 π) equally distributed stochastic variable.

N (t) is the additive white Gaussian noise of channel, and bilateral power spectral density is N ₀/ 2.

Above-mentioned three signals are admitted to the BPSK receiver simultaneously to carry out coherent demodulation and detects the information code element that obtains sending.

As Figure of description 1, when transmitting terminal sends s ₁(t) time, the receiver front end received signal is

Multiplying each other afterwards with local carrier, output signal is

Make Δ f=f _c-f _i, then

1), during Δ f=0

(n is a natural number) sampled value constantly is when t=nT

Because f _cAnd f _c+ f _iVery big, following formula is approximately

Wherein first is required signal component, and second is the simple signal distracter, and the 3rd is channel white Gaussian noise component.

Make stochastic variable

Can be got by probability theory, the probability-distribution function of X is

$F\left(X\right)=\left\{\begin{array}{c}0...x<-1\\ \frac{1}{\mathrm{\&pi;}}(\mathrm{\&pi;}-\arccos x)...-1\&le;x\&le;1\\ 1...x>1\end{array}\right\}---\left(7\right)$

Y satisfies average

Variance Normal distribution.

Therefore send s ₁(t) the bit error probability P (e/s the time ₁) be

$P(e/s_1)=P(Z<0)=P(\frac{{\mathrm{AA}}_{i}T}{2}X+Y<0)$

Order

The probability density function of X, Y is Because X, Y are independent, then

When y＞b, P (e/s ₁)=0;

When y＜-during b,

Wherein

$Q\left(x\right)=\frac{1}{\sqrt{2\mathrm{\&pi;}}}{\&Integral;}_x^{\&infin;}\exp [-\frac{1}{2}{\left(u\right)}^2]\mathrm{du}$

When-b≤y≤b,

$P(e/s_1)={\&Integral;}_{-b}^b\frac{1}{\mathrm{\&pi;}}[\mathrm{\&pi;}-\arccos (-\frac{y}{b})]\frac{1}{{\mathrm{\&sigma;}}_0\sqrt{2\mathrm{\&pi;}}}\exp [-\frac{1}{2}{\left(\frac{y-u}{{\mathrm{\&sigma;}}_0}\right)}^2]\mathrm{dy}$

Can get at last

$P(e/s_1)=Q\left(\frac{b+u}{{\mathrm{\&sigma;}}_0}\right)+{\&Integral;}_{-b}^b\frac{1}{\mathrm{\&pi;}}[\mathrm{\&pi;}-\arccos (-\frac{y}{b})]\frac{1}{{\mathrm{\&sigma;}}_0\sqrt{2\mathrm{\&pi;}}}\exp [-\frac{1}{2}{\left(\frac{y-u}{{\mathrm{\&sigma;}}_0}\right)}^2]\mathrm{dy}---\left(8\right)$

In like manner can get, when sending s ₀(t) bit error probability the time is

$P(e/s_0)=Q\left(\frac{b+u}{{\mathrm{\&sigma;}}_0}\right)+{\&Integral;}_{-b}^b\frac{1}{\mathrm{\&pi;}}\arccos (-\frac{y}{b})\frac{1}{{\mathrm{\&sigma;}}_0\sqrt{2\mathrm{\&pi;}}}\exp [-\frac{1}{2}{\left(\frac{y+u}{{\mathrm{\&sigma;}}_0}\right)}^2]\mathrm{dy}---\left(9\right)$

2), Δ f ≠ 0 o'clock has

(n is a natural number) sampled value constantly is when t=nT

Because f _c, f _c+ f _iVery big, following formula is approximately

Order

With 1) in reasoning identical, can get

Send s ₁(t) bit error probability the time is

$P(e/s_1)=Q\left(\frac{c+u}{{\mathrm{\&sigma;}}_0}\right)+{\&Integral;}_{-c}^c\frac{1}{\mathrm{\&pi;}}[\mathrm{\&pi;}-\arccos (-\frac{y}{c})]\frac{1}{{\mathrm{\&sigma;}}_0\sqrt{2\mathrm{\&pi;}}}\exp [-\frac{1}{2}{\left(\frac{y-u}{{\mathrm{\&sigma;}}_0}\right)}^2]\mathrm{dy}---\left(11\right)$

Send s ₀(t) bit error probability the time is

$P(e/s_0)=Q\left(\frac{c+u}{{\mathrm{\&sigma;}}_0}\right)+{\&Integral;}_{-c}^c\frac{1}{\mathrm{\&pi;}}\arccos (-\frac{y}{c})\frac{1}{{\mathrm{\&sigma;}}_0\sqrt{2\mathrm{\&pi;}}}\exp [-\frac{1}{2}{\left(\frac{y+u}{{\mathrm{\&sigma;}}_0}\right)}^2]\mathrm{dy}---\left(12\right)$

Owing to send s ₁(t) and s ₀(t) statistical probability is equal, receives the error rate in sum and is

$P_e=Q\left(\frac{d+u}{{\mathrm{\&sigma;}}_0}\right)+\frac{1}{2}\left\{\begin{array}{c}{\&Integral;}_{-d}^d\frac{1}{\mathrm{\&pi;}}[\mathrm{\&pi;}-\arccos (-\frac{y}{d})]\frac{1}{{\mathrm{\&sigma;}}_0\sqrt{2\mathrm{\&pi;}}}\exp [-\frac{1}{2}{\left(\frac{y-u}{{\mathrm{\&sigma;}}_0}\right)}^2]\mathrm{dy}\\ +{\&Integral;}_{-d}^d\frac{1}{\mathrm{\&pi;}}\arccos (-\frac{y}{d})\frac{1}{{\mathrm{\&sigma;}}_0\sqrt{2\mathrm{\&pi;}}}\exp [-\frac{1}{2}{\left(\frac{y+u}{{\mathrm{\&sigma;}}_0}\right)}^2]\mathrm{dy}\end{array}\right\}---\left(13\right)$

Wherein during Δ f=0,

Δ f ≠ 0 o'clock,

Formula (13) is the error rate calculation formula of BPSK satellite communication system when disturbed by single-frequency, according to this formula, by the relevant parameter of receiving system and interference signal can obtain present case under system receive the error rate.

And the error rate of BPSK communication system when noiseless is

$P_0=Q\left(\sqrt{\frac{{2E}_b}{N_0}}\right)---\left(14\right)$

Error performance deterioration amount when therefore the BPSK satellite communication system is disturbed by single-frequency is

H＝lg(P _e/P ₀)??????????????(15)

If the patient error rate deterioration amount of initialization system is H ₀, then as H＞H ₀The time, system need disturb at this single-frequency and carry out anti-interference process.

Based on the realization principle of the invention described above, Fig. 2 shows the method flow diagram of detection BPSK satellite communication system error performance deterioration degree provided by the invention, and this method may further comprise the steps:

Step 1: the error rate the when error rate when calculating the BPSK satellite communication system respectively and disturbed by single-frequency and the interference of no single-frequency;

Step 2: the error rate the when error rate when disturbed by single-frequency according to this BPSK satellite communication system and no single-frequency are disturbed, the error performance deterioration amount when calculating BPSK satellite communication system is disturbed by single-frequency;

Step 3: relatively this error performance deterioration amount and predefined error rate deterioration amount threshold value, if this error performance deterioration amount is greater than this threshold value, judge that then error performance severe worsens, disturb at this single-frequency this BPSK satellite communication system is carried out anti-interference process; If this error performance deterioration amount is less than or equal to this threshold value, judge that then error performance does not have severe to worsen, need not this BPSK satellite communication system to be carried out anti-interference process at this single-frequency interference.

Error rate when wherein, the BPSK of calculating described in the step 1 satellite communication system is disturbed by single-frequency comprises: with the carrier wave in the BPSK satellite communication system and noise frequency difference Δ f, bit rate R _b, channel noise power spectrum density N ₀, received signal to noise ratio E _b/ N ₀And carrier/interface ratio (A/A _i) ²The substitution formula

Error rate P when calculating BPSK satellite communication system is disturbed by single-frequency _e, wherein during Δ f=0

Δ f ≠ 0 o'clock

Be the amplitude of BPSK modulation signal, A _iBe the amplitude of single carrier interference signal,

T=1/R _bBe symbol width, Δ f=f _c-f _iBe the difference on the frequency of carrier wave and interference signal, E _bRepresent the signal energy in each code-element period, R _bBe transmission code speed, N ₀Be the channel noise power spectrum density.

The error rate when BPSK of calculating described in the step 1 satellite communication system does not have the single-frequency interference comprises: with the system signal noise ratio E in the BPSK satellite communication system _b/ N ₀The substitution formula

Error rate P when calculating BPSK satellite communication system does not have the single-frequency interference ₀, wherein

E _bBe the signal energy in each code-element period, N ₀Be the channel noise power spectrum density.

The error rate when error rate when disturbed by single-frequency according to this BPSK satellite communication system described in the step 2 and no single-frequency are disturbed, the error performance deterioration amount when calculating the BPSK satellite communication system and disturbed by single-frequency comprises: the error rate P when this BPSK satellite communication system is subjected to the single-frequency interference _eError rate P when disturbing with no single-frequency ₀Substitution formula H=lg (P _e/ P ₀), calculate the error performance deterioration amount H of BPSK satellite communication system when disturbed by single-frequency.

Successful Application of the present invention is in the lunar orbiting exploration engineering, for the anti-interference process of China and co-ordination of Japanese lunar exploration satellite frequency and grounded receiving station provides foundation.The present invention will be described in detail as example below.

In recent years, along with reaching its maturity of technology such as countries in the world carrier rocket, remote observing and controlling and space exploration equipment, the survey of deep space activity is frequent day by day.The phenomenon that the satellite of several countries is surveyed same celestial body has simultaneously appearred.This just makes the satellite of various countries have the possible of mutual interference mutually with the communication of ground station.

In September, 2007, the SELENE lunar exploration satellite of Japan's development (hereinafter to be referred as " day star ") successful launch, SELENE lunar exploration satellite is made of a female satellite and two subsatellites, two subsatellites be respectively " relaying star " (Rstar) and " interferometry satellite " (Vstar).On wherein Rstar is operated in and is 90 ° elliptic orbit apart from moon 100km * 2400km, inclination angle, carry out when female satellite forwards the far-side of the moon to and the data relay task on ground.Vstar carries out tasks such as inverting lunar gravimetry field on then being operated in and being 90 ° elliptic orbit apart from moon 100km * 800km, inclination angle with female satellite.

The same year, lunar orbiting exploration engineering " Chang'e I (CE-1) " the lunar exploration satellite of China's development went up to the air smoothly by the end of October.It operates on the pole orbit of moon 200km, carries out the mapping of lunar surface dimensional topography, surveys the distribution of moon element, assesses tasks such as lunar soil thickness and monitoring space environment.

The TD3 wave beam of CE-1 is as the descending unique channel of detection data, and is most important to whole lunar orbiting exploration engineering.And a day star has dropped in the TD3 transmission band to the VS3 wave beam frequency that International Telecommunication Association reports, and will cause interference to the reception of the descending detection data of CE-1.

Therefore, we need disturb the error rate deterioration situation that the CE-1 data receiving system is caused to assess with regard to day star on the basis of scrutinizing satellite-signal and receiving system parameters.According to its assessment result, carry out the satellite frequency coordination or the CE-1 data receiving system is carried out anti-interference process then with Japanese side.

The TD3 wave beam of CE-1 adopts the BPSK modulation system, and it is descending to be used for detection data, centre frequency 2290MHz, bandwidth 6MHz.According to the data that Japan declares to International Telecommunication Association, a day star VS3 wave beam adopts the single carrier form, and it is descending to be used for observing and controlling, centre frequency 2287.3MHz, and bandwidth 150kHz sees the following form 1, and table 1 is Sino-Japan satellite-signal parameter.Then in fact this problem is equivalent to the BPSK data transmission system under the assessment white Gaussian noise background, and the error rate when disturbed by single carrier worsens situation.

	Day star VS3 wave beam	The CE-1TD3 wave beam
			Frequency range	??2287.238MHz～2287.388MHz	Centre frequency 2290MHz

	Day star VS3 wave beam	The CE-1TD3 wave beam
			Class of emission	20K0NON (necessary bandwidth=20KHz, no modulated carriers (N) do not have modulation (O), no information (N))	6M00GXX BPSK modulation
??EIRP	??21.5dBm	??59dBm

Table 1

Therefore the signal parameter by Sino-Japan satellite can get, and both are about 2.7MHz by difference on the frequency, and the carrier/interface ratio under worst case is about 34.5dB.The CE-1 data receiving system requires under the 3Mbps bit rate, receives the error rate and is better than 1 * 10 ^-6, therefore get the thresholding signal to noise ratio 10.53dB of system.Bringing (13), (14) into calculates noiseless respectively and the error rate when disturbing is arranged.Adopt MALAB numerical calculation instrument, its calculation procedure is as follows:

function[theoryPe，Pe]＝bpskpe(deltaf，SNR，CNI，N0，Rb)

% calculates the theoretical error rate when signal to noise ratio snr

% calculates at f _c-f _i=deltaf, the BPSK receiver error rate during signal to noise ratio snr signal interference ratio SNI

%deltaf represents signal and interfering frequency poor (Hz), signal to noise ratio (dB) when SNR represents that receiving system is noiseless, and CNI represents carrier-to-noise ratio (dB), N ₀Expression demodulation machine input noise spectral density (mw/Hz), R _bExpression transmission code speed

Pi=3.1415; The % circumference ratio

T=1/Rb; The % signal element cycle

The % signal power

Eb=N0*10^ (0.1*SNR); % unit (watt)

A=sqrt (2*Eb/T); The % signal amplitude

The % interference power

Ai＝sqrt(A^2/10^(0.1*CNI))；

The % variable calculates

Ceta=sqrt (Eb*N0/2); The % variance

U=A*A*T/2; The % average

The difference on the frequency of % carrier wave and interference signal (fc=fi)

it?deltaf＝＝0；

d＝A*Ai*T/2；

else

d＝A*Ai*sin(pi*deltaf*T)/(2*pi*deltaf)；

end

The theoretical error rate that % is noiseless

theoryPe＝0.5*erfc(u/(ceta*1.4142))；

% has when the interference error rate

P1＝0.5*erfc((d+u)/(ceta*1.4142))；

fun1＝@(y)(pi-acos(-y/d)).*exp(-0.5*((y-u)/ceta).^2)；

P2＝quadl(fun1，-d，d，1e-9)；

fun2＝@(y)acos(-y/d).*exp(-0.5*((y+u)/ceta).^2)；

P3＝quadl(fun2，-d，d，1e-9)；

Pe＝P1+0.5/(pi*ceta*sqrt(2*pi))*(P2+P3)；

Can receive the P of the error rate when noiseless ₀=9.9932 * 10 ^-7Deteriorate into P _e=9.9988 * 10 ^-7, the error rate deterioration amount that causes is H=2.4 * 10 ^-4DB.Because the CE-1 data receiving system is higher to reliability requirement, therefore the tolerable error performance of system is worsened thresholding and be made as H ₀=0.1dB.H＜H clearly ₀, it is extremely small to the influence of CE-1 data receiving system to illustrate that day star disturbs, and need not carry out anti-interference process in addition to system.

In sum, according to this MATLAB calculation procedure, the difference on the frequency and the carrier/interface ratio of input system received signal to noise ratio, noise spectral density, transmission code speed, transmission carrier wave and interference signal, theory in the time of can obtaining the theory of BPSK communication system when noiseless easily and receive the error rate and disturbed by single-frequency receives the error rate, thereby the error code deterioration situation to system detects, and has certain application value.

Above-described specific embodiment; purpose of the present invention, technical scheme and beneficial effect are further described; institute is understood that; the above only is specific embodiments of the invention; be not limited to the present invention; within the spirit and principles in the present invention all, any modification of being made, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.

Claims (6)

1. method that detects binary phase shift keying satellite communication system error performance deterioration degree is characterized in that this method comprises:

The error rate when error rate when calculating binary phase shift keying BPSK satellite communication system respectively and disturbed by single-frequency and the interference of no single-frequency;

The error rate when error rate when disturbed by single-frequency according to this BPSK satellite communication system and no single-frequency are disturbed, the error performance deterioration amount when calculating BPSK satellite communication system is disturbed by single-frequency;

Relatively this error performance deterioration amount and predefined error rate deterioration amount threshold value worsen if this error performance deterioration amount, is then judged error performance severe greater than this threshold value.

2. the method for detection binary phase shift keying satellite communication system error performance deterioration degree according to claim 1 is characterized in that, the error rate when described calculating BPSK satellite communication system is disturbed by single-frequency comprises:

With the carrier wave in the BPSK satellite communication system and noise frequency difference Δ f, bit rate R _b, channel noise power spectrum density N ₀, received signal to noise ratio E _b/ N ₀And carrier/interface ratio (A/A _i) ²The substitution formula $P_e=Q\left(\frac{d+u}{{\mathrm{\&sigma;}}_0}\right)+\frac{1}{2}\left\{\begin{array}{c}{\&Integral;}_{-d}^d\frac{1}{\mathrm{\&pi;}}[\mathrm{\&pi;}-\arccos (-\frac{y}{d})]\frac{1}{{\mathrm{\&sigma;}}_0\sqrt{2\mathrm{\&pi;}}}\exp [-\frac{1}{2}{\left(\frac{y-u}{{\mathrm{\&sigma;}}_0}\right)}^2]\mathrm{dy}\\ +{\&Integral;}_{-d}^d\frac{1}{\mathrm{\&pi;}}\arccos (-\frac{y}{d})\frac{1}{{\mathrm{\&sigma;}}_0\sqrt{2\mathrm{\&pi;}}}\exp [-\frac{1}{2}{\left(\frac{y+u}{{\mathrm{\&sigma;}}_0}\right)}^2]\mathrm{dy}\end{array}\right\},$ Error rate P when calculating BPSK satellite communication system is disturbed by single-frequency _e, wherein during Δ f=0

Δ f ≠ 0 o'clock

Be the amplitude of BPSK modulation signal, A _iBe the amplitude of single carrier interference signal,

T=1/R _bBe symbol width, Δ f=f _c-f _iBe the difference on the frequency of carrier wave and interference signal, E _bRepresent the signal energy in each code-element period, R _bBe transmission code speed, N ₀Be the channel noise power spectrum density.

3. the method for detection binary phase shift keying satellite communication system error performance deterioration degree according to claim 1 is characterized in that, the error rate when described calculating BPSK satellite communication system does not have the single-frequency interference comprises:

With the system signal noise ratio E in the BPSK satellite communication system _b/ N ₀The substitution formula

Error rate P when calculating BPSK satellite communication system does not have the single-frequency interference ₀, wherein

E _bBe the signal energy in each code-element period, N ₀Be the channel noise power spectrum density.

4. the method for detection binary phase shift keying satellite communication system error performance deterioration degree according to claim 1, it is characterized in that, the described error rate and the error rate of no single-frequency when disturbing when disturbed by single-frequency according to this BPSK satellite communication system, the error performance deterioration amount when calculating the BPSK satellite communication system and being subjected to the single-frequency interference comprises:

Error rate P when disturbed by single-frequency this BPSK satellite communication system _eError rate P when disturbing with this no single-frequency ₀Substitution formula H=lg (P _e/ P ₀), calculate the error performance deterioration amount H of BPSK satellite communication system when disturbed by single-frequency.

5. the method for detection binary phase shift keying satellite communication system error performance deterioration degree according to claim 1 is characterized in that, described relatively this error performance deterioration amount and predefined error rate deterioration amount threshold value further comprise:

If this error performance deterioration amount is less than or equal to this threshold value, judge that then error performance does not have severe to worsen, need not this phase-shift keying satellite communication system to be carried out anti-interference process at this single-frequency interference.

6. the method for detection binary phase shift keying satellite communication system error performance deterioration degree according to claim 1 is characterized in that, described judgement error performance severe worsens, and this method further comprises:

At this single-frequency interference this phase-shift keying satellite communication system is carried out anti-interference process.