JPH03117900A - Receiver - Google Patents

Abstract

PURPOSE:To reduce acceleration carried on an airframe to improve hit precision by selecting an optimum covariance of optimum system noise and observation noise from a Kalman filter covariance table according to measurement noise power with the use of a noise measuring instrument to set in a Kalman filter calculation part to estimate a degree of optimum target addition to add to the output of a proportional navigation calculation part. CONSTITUTION:A noise power measuring instrument 18 measures noise power containing a guide signal which is the output of a FFT circuit 13. A Kalman filter calculation part 15 performs Kalman filter calculation by the use of covariance selected from a covariance table 19 to estimate target acceleration so as to add to the output of a proportional navigation calculation part 14. In a receiver, optimum covariance is selected from a Kalman filter covariance table 19 according to noise power measured with the use of a noise measuring instrument 18 to set in the Kalman filter calculation part 15. Acceleration compensation type proportional navigation is realized by adding an estimation target acceleration to the output of the proportional navigation calculation part 14 to reduce acceleration carried on an airframe so as to improve hit precision.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a receiving device for guiding and controlling a flying object.

[Prior Art] Fig. 2 shows a conventional receiving device, and in Fig. 9, (1)
is an antenna, (2) is a mixer that mixes the receiver signal, (3) is a 9-frequency discriminator, and (4) is a 9-frequency discriminator.

The filter (5) that filters the frequency discriminator is a 9-frequency search controller, (6a) is an amplifier that supplies the voltage of the timing discriminator, and (7) is the filter that filters the clean tooth wave input to the 2-frequency search controller. A clean tooth wave generator that generates
(6b) is a local oscillator amplifier, (8) is a timing search controller, (9) is a timing discriminator, (10) is a timing search controller, (9) is a timing discriminator, (10)
a), (10b) are mixers that mix the received signals to the 9-phase demodulator, (lla), (llb) are 2-phase demodulators, (12) is 1 local oscillator, (13) is.

FFT circuit that performs FFT on video signals (141).

A proportional navigation calculation section (15) performs proportional navigation calculation using the guidance signal output from the FFT circuit. (15) is a Kalman filter calculation section that performs estimation calculation of the target acceleration. (16) is an autopilot calculation unit that outputs a steering angle command, which is an output to the steering device, based on the acceleration command output. Furthermore, (17) is a steering device that outputs a steering angle based on a steering angle command.

[Problems to be Solved by the Invention] Conventional receiving devices use a Kalman filter to estimate target acceleration, and add an acceleration command that outputs the target acceleration, which is the output thereof, by proportional navigation calculation.

However, since the response of the Kalman filter changes due to the disturbance (noise) contained in the induction signal that is the output of the FFT circuit (13), it is not always possible to perform optimal acceleration compensation calculations. As a result, the acceleration of the aircraft generated by the acceleration command input to the autopilot in (16) was sometimes not at the optimal value.

This invention was made to solve the above-mentioned problems, and the estimation of the target acceleration using the Kalman filter is set to the optimum value, thereby reducing the acceleration applied to the aircraft compared to conventional proportional navigation, and improving the accuracy of the target.

[Means for Solving the Problems] A receiving device according to the present invention sets an optimal covariance variance in a Kalman filter calculation section using a noise power measuring device and a Kalman filter covariance table, and optimizes the response of the Kalman filter. be. The Kalman filter algorithm will be explained below. Kalman filter is
As an input observation value, the missile-target deviation (y responsibility n)
) using.

As output, the estimated acceleration of the target x3. Predict.

This can be expressed as the following equation.

x+p(n)=x+g(n-1)+Z, xzgfn
-1)+(z ”/2Hx3g(n-11-a&1(n
-1))X2. (n) =x*t (n-1) +
Te4xst (n-1)-av (n-i) )xs
p (n) ”X3g [n-1)x+gfn)□x+
p(n)+a (n) (y″(n)−X, p(nl
)x, , (n)=x2. (nD(β(n)/τBy responsibilityn
)−xl, (n) 'rxsg(n+・xsp(nD
(2・γ(n)/2)(y″(n) −x 1.
n) )a [n)=P+, (n)/(P+, (n)+
R) β(n)□P2p[n)/ (P+p(n)+Rl
')'(n)11/2)l'3p(n)/ (P+-
(n)+R)Pl-(n)□ (1-a (n)toPI
p (n) pzg (n) = (1-a (n) ip
zp(n)P3g(n)= (1-a (n) 1P3
p(n)Pnr(n)”P4p(n)−β(nl ・P
2- (n)P5g(n)・Psp(nl-β(n)
・P3- (nlpeg(n)=p, (n)-y (n
) ・Pl, (n)P+, (n)□P+rO+:”P2
gO”PagO”P4 t O+p□0+P6,0/2
+Qpzp(n)=p2rO+pagf)+p4gO+
(3/2)P, □0 +pa, 0 +QPsp (n
) =p3f() +PsfO+pag(1+QP4p
(n) ”P4g O+2Psg O+2Pag 0
Pspfn)□Psr()+2Pag()+Qp,p(
n) = ps, 0+q where P: covariance of estimation error R: covariance of observation noise Q covariance of system noise 0 = (n-1) where Q and R are covariance of system noise, covariance of observation noise This is covariance, and this a priori information was required when configuring the filter. In this invention, a noise power measuring device is used to select the optimum value of this a priori information. The method for setting the optimum value is theoretically difficult to derive, so it is performed as follows using a noise power measuring instrument.

■, memory, receiver noise, fading noise,
Set the nominal value of the noise spectrum strength of the receiver noise (.

[Nominal value of Q] 2. The nominal value of R at the nominal value of noise shown in FIG. 3 is confirmed by simulation so as to give an optimal response, and the value is set. [R's thickness value] 3. Calculate the average of the IO samples using the least squares method for the noise svector density measured by the noise power measuring device.

Compare the average value with the nominal value of Q.

The nominal value of R is changed by the weighted value of the deviation.

By the above method, the response of the Kalman filter can be optimized.

[Effect] In this invention, with a noise power measuring device.

Based on the measured noise power, the optimal covariance of system noise and observation noise is selected from the Kalman filter covariance table and set in the Kalman filter calculation section, thereby estimating the optimal target acceleration and calculating the optimal covariance of the proportional navigation calculation section. By adding this to the output, the acceleration applied to each aircraft is reduced, and the accuracy of hitting is improved.

[Example] Examples of the present invention will be described below.

In FIG. 1, (1) to (17) are the same as the conventional receiving device. (18) is a noise power measuring device that measures the noise power included in the induced signal that is the output of the FFT circuit (13), and (19) is a part that stores two covariance tables selected depending on the noise power. (15) is a Kalman filter calculation unit that performs Kalman filter calculation using the covariance selected in (19). Here, the target acceleration is estimated and added to the output of the proportional navigation calculation unit (I4). match.

Next, the operation will be explained.

In this receiving device, the optimal covariance is selected using the Kalman filter covariance table (19) based on the noise power measured by the noise measuring device (18), and (15)
By setting it in the Kalman filter calculation section and adding the estimated target acceleration to the output of the proportional navigation calculation section,
It realizes acceleration-compensated proportional navigation, reduces the acceleration applied to the two aircraft, and improves accuracy.

[Effects of the Invention] As described above, according to the present invention, a noise power measuring device and a Kalman filter covariance table can be used.

By selecting the optimal covariance, calculating the target acceleration in the Kalman filter calculation section, and adding it to the output of the proportional navigation calculation section, it becomes the optimal acceleration command, and by manually inputting it to the autopilot calculation section, the acceleration applied to the nine aircraft can be calculated. It is possible to minimize the damage and improve accuracy.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a receiving device according to an embodiment of the present invention;
FIG. 2 is a diagram showing a conventional receiving device. In the figure, (1) is an antenna, (2) is a mixer,
(3) is a frequency discriminator, and (4) is a filter. (5) is a single frequency search controller, and (6) is an amplifier. (7) is a sharp tooth wave generator, (8) is a timing search controller, (9) is a timing discriminator, [10] is a mixer, (11) is a 9-phase demodulator, (12) is a ) is 9
Local oscillator, (13) is FFT circuit, (14) is
proportional navigation calculation section, (15) is Kalman filter calculation section, (16) is autopilot calculation section, (17
) is a steering device, (18) is a noise power measuring device,
(19) is the Kalman filter covariance table. Note that the same reference numerals in FIG. 9 indicate the same or equivalent parts.

Claims (1)

[Claims] Antenna, phase modulator, timing discriminator for controlling the timing of phase modulating the received signal, frequency discriminator for demodulating frequency displacement, filter, frequency search controller, tooth-tooth wave generator, timing discriminator a timing search controller that controls the timing of the amplifier, a local oscillator, and an FFT that processes the video signal.
circuit, a proportional navigation calculation section that performs proportional navigation calculations using the guidance signal that is its output, and an FFT output of the guidance signal.
A noise power measuring device that measures noise power, a Kalman filter covariance table that selects the optimal Kalman filter covariance from the measured noise power, and a prediction calculation of the target acceleration using the optimal covariance. The autopilot calculation unit outputs the rudder angle command using the compensation acceleration command, which is the sum of the target acceleration output from the Kalman filter calculation unit and the acceleration command output from the proportional navigation calculation unit, and the rudder angle command. A receiving device equipped with a steering device that outputs a steering angle.