A method for anti-interference measurement and control communication with capacity expansion

Abstract

The application discloses a kind of methods for expanding anti-interference TT&C communication, including step 1, generating M alternative spread spectrum sequences;Step 2, transmitting end parallel combination spread spectrum, including parallel transmission, spread spectrum superposition and carrier modulation;Wherein, spread spectrum, in I and Q, any one alternative spread spectrum sequence in optional one way is as synchronization sequence, and the combination spread spectrum is carried out to all remaining alternative spread spectrum sequences;Step 3, receiving end blind interference signal separation: at receiving end, first, all interference signals and TT&C signals received by array antenna are carrier demodulated, then the observed signal after carrier demodulation is carried out blind interference signal separation, and the separated expanded anti-interference TT&C signal is obtained;Finally, the expanded anti-interference TT&C signal is recovered, and recovery data is obtained.The application organically combines parallel combination spread spectrum and blind interference signal separation processing, can improve the capacity of system while guaranteeing the anti-interference ability of TT&C system.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of spaceflight TT&C communication, in particular to a method for expanding capacity and resisting interference of TT&C communication. BACKGROUND

[0002] The spaceflight TT&C system provides reliable and accurate tracking, measurement and command control for the launch and on-orbit operation of a spacecraft, and is an important component for ensuring the normal operation of the spacecraft in spaceflight engineering. With the rapid development of spaceflight technology, the number of parameters of a spacecraft is increasing, and the amount of data generated during operation is also increasing, which has put forward an urgent demand for high code rate data transmission. Meanwhile, the openness of the spaceflight TT&C link determines that it is extremely vulnerable to various types of electromagnetic interference, especially high-power malicious interference. The enemy can use electronic warfare aircraft, accompanying small satellites and other platforms to implement electromagnetic interference on the spaceflight TT&C link of our country. When the interference intensity is greater than the system tolerance limit, the TT&C signal cannot be normally demodulated, resulting in the interruption of the TT&C communication link of our country, which will greatly affect the command and decision-making of our country in wartime. Therefore, the spaceflight TT&C link needs to have both high code rate data transmission capability and sufficient anti-interference capability, so as to ensure the efficiency and reliability of TT&C data transmission.

[0003] At present, the TT&C system usually adopts a non-coherent spread spectrum TT&C system to achieve anti-interference purpose. Although it can improve the received signal-to-noise ratio to a certain extent, it still has the following shortcomings in use, which need to be improved.

[0004] 1. In the process of receiver despreading of the spread spectrum communication system, the interference amplitude is reduced, but the interference frequency band is widened. Essentially, the frequency resource is exchanged for the improvement of reliability.

[0005] 2. The conventional direct spread waveform spreads the signal with a single pseudo-code spread spectrum sequence, and only carries 1 bit of data per pseudo-code period, so the frequency band utilization rate is low, and high code rate data transmission cannot be realized.

[0006] 3. The traditional parallel combined spread spectrum technology can carry more bits of data per pseudo-code period through the pseudo-code combination relationship, and improve the system frequency band utilization rate. However, the problem is that multiple pseudo-codes share power, which will cause the reduction of the system interference tolerance. SUMMARY

[0007] The technical problem to be solved by the present application is to solve the shortcomings of the prior art, and to provide a method for expanding capacity and resisting interference of TT&C communication. The method for expanding capacity and resisting interference of TT&C communication combines parallel combined spread spectrum with blind jamming signal separation processing, and can improve the system capacity while ensuring the anti-interference ability of the TT&C system.

[0008] To solve the above technical problems, the technical scheme adopted by the present application is as follows:

[0009] A method for anti-interference telemetry and control communication with capacity expansion, comprising the following steps.

[0010] Step 1, generating M alternative spread spectrum sequences for the transmitting end and the receiving end of a telemetry and control link.

[0011] Step 2, parallel combination of spread spectrum at the transmitting end, comprising:

[0012] Step 2-1, parallel transmission: at the transmitting end, serial-to-parallel conversion is performed on the sending data to form I and Q two-way bit parallel transmission.

[0013] Step 2-2, spread spectrum and superposition: in I and Q, any one of the alternative spread spectrum sequences in the optional one is taken as a synchronization sequence, and spread spectrum is performed on all the remaining alternative spread spectrum sequences; then, the I and Q spread spectrum sequences are superimposed respectively to form I and Q two-way combined sequence signals; wherein the synchronization sequence participates in the sequence superposition of the corresponding way.

[0014] Step 2-3, carrier modulation: I and Q two-way combined sequence signals are carrier modulated to form an anti-interference telemetry and control waveform signal with capacity expansion.

[0015] Step 3, blind jammer separation at the receiving end: at the receiving end, first, carrier demodulation is performed on all the interference signals and telemetry and control signals received by the array antenna, and then blind jammer separation is performed on the observed signals after carrier demodulation to obtain separated anti-interference telemetry and control signals with capacity expansion; finally, the anti-interference telemetry and control signals with capacity expansion are recovered to obtain recovered data.

[0016] In step 1, the M alternative spread spectrum sequences generated have good autocorrelation and cross-correlation characteristics, which are PN1, PN2, …, PN M .

[0017] In step 2-2, let PN M be the synchronization sequence selected in I, in step 2-1, let the sending data be N S , and let I and Q two-way bit parallel be N I bit parallel and N Q bit parallel; then:

[0018]

[0019] In the formula, P represents the possibility of selecting r pseudo-codes from M pseudo-codes for combination, represents the floor function.

[0020] P represents the possibility of selecting r pseudo-codes from M-1 pseudo-codes for combination.

[0021] In step 2-2, N IMethods for bit-parallel combination spread spectrum and superposition include:

[0022] Step 2-2A1: Divide the I-channel data into r bits and Two bits.

[0023] Step 2-2A2, for The communication data corresponding to the bit segment is divided into PN1PN2…PN M-1 Data-spreading sequence mapping yields r spreading sequences.

[0024] Step 2-2A3: Determine the polarity of the r spread spectrum sequences based on the communication data corresponding to the r bit segments.

[0025] Step 2-2A4: Superimpose the selected r spread spectrum sequences with different polarities, and simultaneously superimpose the synchronization sequence PN. M The combined I-channel sequence signal d at time t is obtained. I (t), the expression is:

[0026]

[0027] In the formula, q j Let be the polarity of the j-th spreading sequence in the I-path, taking a value of +1 or -1; where 1≤j≤r.

[0028] PN j (t) represents the j-th spread spectrum sequence in the I-path at time t.

[0029] In step 2-2, N Q Methods for bit-parallel combination spread spectrum and superposition include:

[0030] Step 2-2B1: Divide the Q-channel data into r bits and Two bits.

[0031] Step 2-2B2, for The communication data corresponding to the bit segment is divided into PN1PN2…PN M Data-spreading sequence mapping yields r spreading sequences.

[0032] Step 2-2B3: Determine the polarity of the r spread spectrum sequences based on the communication data corresponding to the r bit segments.

[0033] Step 2-2B4: Superimpose the selected r spread spectrum sequences with different polarities to obtain the Q-channel combined sequence signal d at time t. Q (t), the expression is:

[0034]

[0035] In the formula, q iLet be the polarity of the i-th spreading sequence in the Q-path, taking a value of +1 or -1; where 1≤i≤r.

[0036] PN i (t) represents the i-th spreading sequence in the Q-path at time t.

[0037] In steps 2-3, the expression for the expanded anti-interference measurement and control waveform signal s(t) is:

[0038]

[0039] In the formula, d I (t) represents the I-channel combined sequence signal at time t.

[0040] d Q (t) represents the Q-channel combined sequence signal at time t.

[0041] f c The carrier frequency is known. The carrier phase is known.

[0042] Step 3, receiver blind interference signal separation, includes:

[0043] Step 3-1, Carrier Demodulation: At the receiving end, M in the array antenna R Each antenna demodulates the N interference signals and telemetry signals it receives, obtaining M. R Road observation signal.

[0044] Step 3-2, Blind interference signal separation: Separate M R The road observation signal is subjected to blind interference signal separation to obtain N+1 separated signals.

[0045] Step 3-3: Obtain the expanded anti-interference measurement and control signals: Extract the I-channel data of each separated signal and compare it with the synchronization sequence PN. M Perform relevant calculations, obtain the estimated expanded anti-interference measurement and control signal through maximum value determination and polarity recovery, and then use... To express.

[0046] Steps 3-4: Recovery: First, extract the I and Q data from the expanded anti-interference measurement and control signal, and recover the I and Q bits in parallel. Then, perform parallel-to-serial conversion to form the recovered data.

[0047] In step 3-2, the separation of blind interference signals includes:

[0048] Step 3-2A, Whitening Pretreatment: M R The observed signals are preprocessed by whitening to obtain N+1 whitened signals.

[0049] Step 3-2B, Blind interference signal separation: Perform blind interference signal separation on the N+1 whitened signals so that the separated signal y is approximately the same as the source signal S.

[0050] Steps 3-4, the recovery process, includes the following steps:

[0051] Step 3-4A: Extract I and Q data from the expanded anti-interference measurement and control signals respectively.

[0052] Step 3-4B, I-channel recovery: Restore the I-channel data to PN1, PN2, ... PN M-1 Perform the relevant operations separately, and obtain the restored N through maximum value determination, polarity recovery, and data-sequence inverse mapping. I Bit-parallel data.

[0053] Step 3-4C, Q-path recovery: Compare the Q-path data with PN1, PN2, ... PN M Perform the relevant operations separately, and obtain the restored N through maximum value determination, polarity recovery, and data-sequence inverse mapping. Q Bit-parallel data.

[0054] Steps 3-4D: N I and N Q Bit-parallel data is converted from parallel to serial to obtain N. S Bit recovery data.

[0055] In step 3-2B, when performing blind interference separation on the N+1 whitened signals, the complex mixing model is first converted into a real mixing model to eliminate the effect of phase ambiguity.

[0056] The present invention has the following beneficial effects:

[0057] 1. This invention achieves the goal of simultaneously improving system transmission capacity and interference tolerance by organically combining parallel combined spread spectrum (to improve waveform) at the transmitting end with blind interference signal separation at the receiving end.

[0058] 2. At the transmitting end, the data carrying capacity is expanded by using the pseudo-code combination relationship of parallel combined spread spectrum and the orthogonal transmission mode of I and Q paths.

[0059] 3. At the receiving end, by separating blind interference signals, the interference tolerance of the spread spectrum system can be further improved without increasing additional spectrum overhead. Attached Figure Description

[0060] Figure 1 The schematic diagram of the parallel combined spread spectrum at the transmitter in this invention is shown.

[0061] Figure 2 The schematic diagram of the receiver blind interference signal separation in this invention is shown.

[0062] Figure 3 The simulation comparison diagram shows the anti-interference capability of the present invention and the traditional non-coherent spread spectrum telemetry and communication system. Detailed Implementation

[0063] The present invention will now be described in further detail with reference to the accompanying drawings and specific preferred embodiments.

[0064] like Figure 1 and Figure 2 As shown, an extended anti-interference telemetry and control communication method includes the following steps.

[0065] Step 1: Generate M alternative spread spectrum sequences for use at the transmitter and receiver of the telemetry and control link.

[0066] The above M candidate spreading sequences must have good autocorrelation and cross-correlation characteristics, and are respectively PN1, PN2, ... PN M .

[0067] Step 2: Parallel combined spread spectrum at the transmitting end, such as... Figure 1 As shown, the steps include the following.

[0068] Step 2-1, Parallel Transmission: At the transmitting end, for the transmitted data N... S Perform serial-to-parallel conversion to form two parallel bit transmission paths, I and Q, which are N respectively. I Bit parallelism and N Q If bits are parallel, then:

[0069]

[0070] In the formula, This represents the probability of selecting r pseudocodes from M pseudocodes for combination. This indicates rounding down to the nearest integer.

[0071] This represents the probability of selecting r pseudocodes from M-1 pseudocodes for combination.

[0072] Step 2-2, Spread Spectrum and Superposition

[0073] In I and Q, any one of the candidate spreading sequences from any path is selected as the synchronization sequence, and all the remaining candidate spreading sequences are spread.

[0074] In this example, the PN in the I path is selected. M As a synchronization sequence. At this time, the synchronization sequence PN M It can serve as both a synchronization signal for the transmitting and receiving parties and a correlation sequence for extracting and restoring the polarity of the expanded anti-interference signal after blind interference signal separation at the receiving end. Alternatively, any alternative spreading sequence from the Q-channel can be selected, such as PN. MAs a synchronization sequence, etc.

[0075] A. The above N I The method of bit parallel combination spread spectrum and superposition preferably includes the following steps.

[0076] Step 2-2A1: Divide the I-channel data into r bits and Two bits.

[0077] Step 2-2A2, for The communication data corresponding to the bit segment is divided into PN1PN2…PN M-1 Data-spreading sequence mapping yields r spreading sequences.

[0078] Step 2-2A3: Determine the polarity of the r spread spectrum sequences based on the communication data corresponding to the r bit segments.

[0079] Step 2-2A4: Superimpose the selected r spread spectrum sequences with different polarities, and simultaneously superimpose the synchronization sequence PN. M The combined I-channel sequence signal d at time t is obtained. I (t), the expression is:

[0080]

[0081] In the formula, q j Let be the polarity of the j-th spreading sequence in the I-path, taking a value of +1 or -1; where 1≤j≤r.

[0082] PN j (t) represents the j-th spread spectrum sequence in the I-path at time t.

[0083] B. The above N Q The method of bit parallel combination spread spectrum and superposition preferably includes the following steps.

[0084] Step 2-2B1: Divide the Q-channel data into r bits and Two bits.

[0085] Step 2-2B2, for The communication data corresponding to the bit segment is divided into PN1PN2…PN M Data-spreading sequence mapping yields r spreading sequences.

[0086] Step 2-2B3: Determine the polarity of the r spread spectrum sequences based on the communication data corresponding to the r bit segments.

[0087] Step 2-2B4: Superimpose the selected r spread spectrum sequences with different polarities to obtain the Q-channel combined sequence signal d at time t. Q (t), the expression is:

[0088]

[0089] In the formula, q i Let be the polarity of the i-th spreading sequence in the Q-path, taking a value of +1 or -1; where 1≤i≤r.

[0090] PN i (t) represents the i-th spreading sequence in the Q-path at time t.

[0091] Step 2-3, Carrier Modulation: The combined I and Q signals are carrier modulated to form an extended anti-interference measurement and control waveform signal s(t), expressed as:

[0092]

[0093] In the formula, d I (t) represents the I-channel combined sequence signal at time t.

[0094] d Q (t) represents the Q-channel combined sequence signal at time t.

[0095] f c The carrier frequency is known. The carrier phase is known.

[0096] Step 3, receiver blind interference signal separation, preferably includes the following steps.

[0097] Step 3-1, Carrier Demodulation: At the receiving end, M in the array antenna R Each antenna demodulates the N interference signals and telemetry signals it receives, obtaining M. R Road observation signal.

[0098] The satellite-to-ground data transmission channel can be approximated as an additive white Gaussian noise channel. During transmission through this channel, telemetry and control signals are not only affected by noise but may also be subject to various intentional and unintentional interferences. Assume the number of interference sources is N. For example... Figure 2 As shown, at the receiving end of the telemetry and communication system, an array antenna is used for signal reception. It is assumed that the array antenna is a uniform linear array with M elements. R Let θ S and θ v (v=1,2,...,N) represent the elevation angles of the incoming wave direction of the extended anti-interference measurement and control signal and each interference, respectively. Then the array direction vectors of the signal and interference are:

[0099]

[0100] in:

[0101]

[0102] In the formula, λ and f represent the signal wavelength and frequency, respectively, and c = 3 × 10⁻⁶. 8 m / s represents the speed of propagation of the incident wave.

[0103] a(θ S ) represents the array direction vector of the expanded anti-interference measurement and control signal.

[0104] a(θ v Let ) represent the array direction vector of the v-th interference, and 1≤v≤N.

[0105] Let P S,r and P v,r (v=1,2,...,N) represent the expansion anti-interference measurement and control signal at the front end of the receiving antenna and the v-th interference power, respectively. v (t)(v=1,2,...,N) represents the interference from each path. The signal received by each element antenna of the linear array can then be expressed as:

[0106]

[0107] In the formula, They represent the 1st, 2nd, ..., Mth, respectively. R The observed signals from each antenna.

[0108] They represent the 1st, 2nd, ..., Mth, respectively. R The noise vector of each antenna.

[0109] The received signal is demodulated by carrier wave to obtain M. R The roadbed observation signal, when expressed in matrix form, is:

[0110] x(t) = AS(t) + n(t)

[0111] in:

[0112]

[0113] A=[a(θ S )a(θ1)…a(θ N )]

[0114]

[0115] In the formula, x(t), A, S(t), and n(t) represent the observed signal vector, the mixing matrix, the source signal vector, and the noise vector, respectively.

[0116] The ratio of signal power to interference power is When the interference intensity is high, causing the interference-to-signal ratio to exceed the system interference tolerance, normal demodulation of the measurement and control signals will not be possible based solely on the signal received by the array antenna.

[0117] Step 3-2, Separation of Blind Interference Signals

[0118] The expanded anti-interference measurement and control signal and the interference come from different physical sources and transmit different information. They satisfy statistical independence. Therefore, the interference-laden expanded anti-interference measurement and control signal can be processed by blind interference signal separation to obtain a relatively pure measurement and control signal.

[0119] The above-mentioned blind interference signal separation preferably includes the following steps.

[0120] Step 3-2A, Whitening Pretreatment: M R The observed signals are preprocessed by whitening to obtain N+1 whitened signals.

[0121] like Figure 2 As shown, M R The observed signals are first preprocessed by whitening to obtain N+1 whitened signals. Let V represent the whitening matrix, then the whitened signal z = Vx satisfies E{zz} H The property of} = I. The specific treatment method for whitening is:

[0122] Perform eigenvalue decomposition on the correlation matrix of x:

[0123] R x =E{xx H}=UΣU H

[0124] By E{zz H}=VE{xx H}V H As can be seen from I, the whitening matrix can be taken as...

[0125]

[0126] In the formula, Λ s U is a diagonal matrix composed of the non-zero eigenvalues ​​of Σ. s It is the eigenvector matrix composed of the eigenvectors corresponding to the non-zero eigenvalues ​​in U.

[0127] Step 3-2B, Separation of Blind Interference Signals

[0128] The core of blind interference signal separation lies in guiding the separation matrix W to iterate by solving the objective function h[W], so that the result y of its interaction with the whitened signal z is an approximation of the source signal S.

[0129] Since the baseband signal to be processed is a complex-valued signal, the separated source signals exhibit phase ambiguity, which will affect the polarity recovery of subsequent I-channel and Q-channel r-bit data. Therefore, by fully utilizing the independence of the I-channel and Q-channel data in the extended anti-interference measurement and control signal, the complex-number mixture model is transformed into a real-number mixture model to eliminate the influence of phase ambiguity. Taking one-channel interference (N=1) as an example, the two complex-number mixture signals after whitening can be transformed into four real-number mixture signals, which are formed by mixing the four independent real and imaginary parts of the two complex source signals. That is, the complex form of the mixture signal is:

[0130]

[0131] Converting it to real number form, we get:

[0132]

[0133] In the above formula, the subscripts r and i represent the real and imaginary parts of each variable, respectively. The normalized EASI algorithm is used to estimate the separation matrix W for the above real-form mixed signal. uk This is called the unconstrained separation matrix, and let...

[0134]

[0135] In the above formula, w uij ,i,j=1,2,3,4 represent the unconstrained separation matrix W uk The elements of the normalized EASI algorithm. The separation rule is as follows:

[0136]

[0137] Where g(·) is a nonlinear function related to the statistical characteristics of the source signal, and y k =W uk (k)x(k) is the separated signal. The correctly separated signal y at time k is... k =W uk (k)x(k) should have the following form:

[0138]

[0139] In order to correctly combine the separated real signals to form the complex source signal that needs to be estimated, the separation matrix W... uk By applying constraints of the following form, we obtain the constraint separation matrix W. k :

[0140]

[0141] When N > 1, the N+1 complex mixed signals after whitening are transformed into 2(N+1) real mixed signals, which are composed of the 2(N+1) independent real and imaginary parts of the N+1 complex source signals. The normalized EASI algorithm is used to obtain a 2(N+1)×2(N+1) dimensional unconstrained separation matrix W in each iteration. uk Then, through the above constraint relationships, the constraint separation matrix W is obtained. k Thus ensuring y k =W k The real signals separated by x(k) are correctly combined together, while the phase ambiguity of the separated complex signals is removed.

[0142] Step 3-3: Obtain the expanded anti-interference measurement and control signals: Extract the I-channel data of each separated signal and compare it with the synchronization sequence PN. M Perform relevant calculations, obtain the estimated expanded anti-interference measurement and control signal through maximum value determination and polarity recovery, and then use... To express.

[0143] Steps 3-4: Recovery: First, extract the I and Q data from the expanded anti-interference measurement and control signal, and recover the I and Q bits in parallel. Then, perform serial-to-parallel conversion to form the recovered data.

[0144] In steps 3-4, the recovery process preferably includes the following steps.

[0145] Step 3-4A: Extract I and Q data from the expanded anti-interference measurement and control signals respectively.

[0146] Step 3-4B, I-channel recovery: Restore the I-channel data to PN1, PN2, ... PN M-1 Perform the relevant operations separately, and obtain the restored N through maximum value determination, polarity recovery, and data-sequence inverse mapping. I Bit-parallel data.

[0147] Extract the I-branch data of the estimated extended capacity anti-interference signal. and Q branch data Perform despreading and data-sequence inverse mapping operations separately. Specifically, Correlation operations are performed on the M-1 spreading sequences identical to those at the transmitter. The output signal of any correlator can be expressed as...

[0148]

[0149] Where, n i (t) represents the output noise signal after the correlator. The result of the correlation operation is used to determine the maximum value, selecting r spreading sequences, which are then passed through a data-to-sequence inverse mapper to obtain... Bit data, combined with polarity information q I,i We obtain r bits of data, which together constitute... Bit-parallel data recovery.

[0150] Step 3-4C, Q-path recovery: Compare the Q-path data with PN1, PN2, ... PN M Perform the relevant calculations separately, and obtain the restored N by determining the maximum value and restoring the polarity. Q Bit-parallel data.

[0151] Will Correlation operations are performed on M spreading sequences identical to those at the transmitter. The output signal of any correlator can be expressed as...

[0152]

[0153] The results of the relevant operations are used to determine the maximum value, and r spreading sequences are selected. Then, the results are passed through a data-sequence inverse mapper to obtain... Bit data, combined with polarity information q Q,i We obtain r bits of data, which together constitute... Bit-parallel data recovery.

[0154] Steps 3-4D: N I Bit-parallel data and N Q Bit-parallel data is merged and denoted as:

[0155]

[0156] Next, a parallel-to-serial conversion is performed to obtain N from the transmitting end. S Bit recovery data.

[0157] The anti-interference measurement and control communication method proposed in this invention has an anti-interference capability compared with the traditional non-coherent spread spectrum measurement and control communication system. Figure 3 As shown, the horizontal axis represents the signal-to-interference power ratio (SJR), and the vertical axis represents the bit error rate (BER). The interference type is wideband interference, and the interference bandwidth is half the signal bandwidth. Both schemes use the same type of spreading code, with a spreading code length of 32, i.e., a spreading gain of 15dB. M is set to 32, and r is set to 2. From... Figure 3 As can be seen, when the interference intensity is large enough to exceed the system interference tolerance, the bit error rate performance of the traditional noncoherent spread spectrum telemetry and control communication system drops sharply. However, the bit error rate performance of the extended anti-interference telemetry and control communication method proposed in this invention hardly changes with SJR. This is mainly because even when SJR is low, blind interference signal separation can still achieve a good signal and interference separation effect, thereby improving the system interference tolerance.

[0158] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various equivalent transformations can be made to the technical solutions of the present invention, and these equivalent transformations all fall within the protection scope of the present invention.

Claims

1. A method for expanding capacity and resisting interference in telemetry and control communication, characterized in that: Includes the following steps: Step 1: Generate M candidate spread spectrum sequences for use at the transmitter and receiver ends of the telemetry and control link; Step 2: Parallel combined spread spectrum at the transmitting end, including: Step 2-1, Parallel Transmission: At the transmitting end, the transmitted data is converted from serial to parallel to form two bit parallel transmission paths, I and Q. Step 2-2, Spreading and Superposition: In I and Q, any candidate spreading sequence from either path is selected as the synchronization sequence, and all remaining candidate spreading sequences are spread. Then, the spread sequences of I and Q are combined and superimposed to form two combined sequence signals, I and Q. The synchronization sequence participates in the superposition of the corresponding path. Steps 2-3: Carrier modulation: The combined I and Q signals are carrier modulated to form an expanded anti-interference measurement and control waveform signal; Step 3, Blind interference signal separation at the receiving end: At the receiving end, all interference signals and telemetry and control signals received by the array antenna are first carrier demodulated, and then the carrier demodulated observation signals are blind interference signal separated to obtain the separated extended anti-interference telemetry and control signals; finally, the extended anti-interference telemetry and control signals are recovered to obtain the recovered data.

2. The expanded anti-interference telemetry and communication method according to claim 1, characterized in that: In step 1, the generated M candidate spreading sequences have autocorrelation and cross-correlation properties, and are PN1, PN2, ... PN1. M .

3. The expanded anti-interference measurement and control communication method according to claim 2, characterized in that: In step 2-2, let PN in the selected I path be... M As a synchronization sequence, in step 2-1, the data to be sent is set to N. S The I and Q channels are parallel to each other, with N bits each. I Bit parallelism and N Q Bit parallelism; then: In the formula, This represents the probability of selecting r pseudocodes from M pseudocodes for combination. Indicates rounding down; This represents the probability of selecting r pseudocodes from M-1 pseudocodes for combination.

4. The expanded anti-interference measurement and control communication method according to claim 3, characterized in that: In step 2-2, N I Methods for bit-parallel combination spread spectrum and superposition include: Step 2-2A1: Divide the I-channel data into r bits and Two bits; Step 2-2A2, for The communication data corresponding to the bit segment is divided into PN1PN2…PN M-1 Data-spreading sequence mapping yields r spreading sequences; Step 2-2A3: Determine the polarity of the r spreading sequences based on the communication data corresponding to the r bit segments; Step 2-2A4: Superimpose the selected r spread spectrum sequences with different polarities, and simultaneously superimpose the synchronization sequence PN. M The combined I-channel sequence signal d at time t is obtained. I (t), the expression is: In the formula, q j Let be the polarity of the j-th spreading sequence in path I, taking a value of +1 or -1; where 1≤j≤r; PN j (t) represents the j-th spread spectrum sequence in the I-path at time t.

5. The expanded anti-interference measurement and control communication method according to claim 3, characterized in that: In step 2-2, N Q Methods for bit-parallel combination spread spectrum and superposition include: Step 2-2B1: Divide the Q-channel data into r bits and Two bits; Step 2-2B2, for The communication data corresponding to the bit segment is divided into PN1PN2…PN M Data-spreading sequence mapping yields r spreading sequences; Step 2-2B3: Determine the polarity of the r spreading sequences based on the communication data corresponding to the r bit segments; Step 2-2B4: Superimpose the selected r spread spectrum sequences with different polarities to obtain the Q-channel combined sequence signal d at time t. Q (t), the expression is: In the formula, q i Let be the polarity of the i-th spreading sequence in the Q-path, taking a value of +1 or -1; where 1≤i≤r; PN i (t) represents the i-th spreading sequence in the Q-path at time t.

6. The expanded anti-interference telemetry and communication method according to claim 1, characterized in that: In steps 2-3, the expression for the expanded anti-interference measurement and control waveform signal s(t) is: In the formula, d I (t) represents the I-channel combined sequence signal at time t; d Q (t) represents the Q-channel combined sequence signal at time t; f c The carrier frequency is known. The carrier phase is known.

7. The expanded anti-interference telemetry and communication method according to claim 3, characterized in that: Step 3, receiver blind interference signal separation, includes: Step 3-1, Carrier Demodulation: At the receiving end, M in the array antenna R Each antenna demodulates the N interference signals and telemetry signals it receives, obtaining M. R Road observation signal; Step 3-2, Blind interference signal separation: Separate M R The road observation signal is subjected to blind interference signal separation to obtain N+1 separated signals; Step 3-3: Obtain the expanded anti-interference measurement and control signals: Extract the I-channel data of each separated signal and compare it with the synchronization sequence PN. M Perform relevant calculations, obtain the estimated expanded anti-interference measurement and control signal through maximum value determination and polarity recovery, and then use... The process involves: Step 3-4, recovery: First, extract the I and Q data from the expanded anti-interference measurement and control signal, and then recover the I and Q bits in parallel. Next, perform serial-to-parallel conversion to form the recovered data.

8. The expanded anti-interference measurement and control communication method according to claim 7, characterized in that: In step 3-2, the separation of blind interference signals includes: Step 3-2A, Whitening Pretreatment: M R The observed signals are preprocessed by whitening to obtain N+1 whitened signals; Step 3-2B, Blind interference signal separation: Perform blind interference signal separation on the N+1 whitened signals so that the separated signal y is approximately the same as the source signal S.

9. The expanded anti-interference measurement and control communication method according to claim 7, characterized in that: Steps 3-4, the recovery process, includes the following steps: Step 3-4A: Extract I and Q data from the expanded anti-interference measurement and control signals respectively; Step 3-4B, I-channel recovery: Restore the I-channel data to PN1, PN2, ... PN M-1 Perform the relevant operations separately, and obtain the restored N through maximum value determination, polarity restoration, and data-sequence inverse mapping operations. I Bit-parallel data; Step 3-4C, Q-path recovery: Compare the Q-path data with PN1, PN2, ... PN M By performing relevant operations, including maximum value determination, polarity recovery, and data-sequence inverse mapping, the recovered N is obtained. Q Bit-parallel data; Steps 3-4D: N I Bit-parallel data and N Q Bit-parallel data is converted from parallel to serial to obtain N. S Bit recovery data.

10. The expanded anti-interference measurement and control communication method according to claim 8, characterized in that: In step 3-2B, when performing blind interference separation on the N+1 whitened signals, the complex mixing model is first converted into a real mixing model to eliminate the effect of phase ambiguity.

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