JPH04804A - Adaptive array antenna system - Google Patents

Abstract

PURPOSE:To secure communication in the state of making the level of a signal wave higher than the level of an interference wave by providing a comparing and deciding means to compare and decide the size of the level by detecting the respective signal waves concerning the output of a power inversion correlation processing means and an output received from one of first and second array antennas, and detecting the level of the detected signal wave to the interference wave. CONSTITUTION:A weight control circuit 17 is provided to output signals while multiplying weight to input signals, and mixing them corresponding to a control signal from a correlation processing circuit 18, and the output signals are supplied to the correlation processing circuit 18 and also supplied to a signal switching circuit 19 and a switching control circuit 20 as a power inversion (PI) system. The correlation processing circuit 18 executes a PI correlation processing while inputting the output signal (through system) of an IF amplifier 16 and the output signal (PI system) of the weight control circuit 17 so as to decide the weight amount of the weight control circuit 17 corresponding to the processed result. A comparison and decision circuit 205 decides the size by comparing the signal wave/interference wave (S/J) level of each demodulated data obtained in the through and PI systems, and the switch of the signal switching circuit 20 is controlled corresponding to the decided result.

Description

DETAILED DESCRIPTION OF THE INVENTION [Purpose of the Invention (Industrial Application Field) The present invention relates to an adaptive array antenna device using a power inversion algorithm that removes interference waves and enables communication.

(Prior Art) As is well known, in an environment where there are interference waves stronger than signal waves, a power inversion (hereinafter referred to as PI) algorithm is used in an adaptive array antenna device. This antenna device using PI has input/output power characteristics as shown in FIG. That is,
When the PI is off, the characteristic is linear, but when the PI is on, when the signal input is increased beyond a certain input level point, the output level is suppressed. Power inversion correlation processing is a method that utilizes this effect to suppress interference waves that are stronger than signal waves. Specifically, in the PI off state, the fifth
When the level of the interference wave J is higher than the level of the desired signal S, as shown in Figure 5(a), by setting P1 on, the interference wave J is set to be higher than the desired signal S, as shown in Figure 5(b). Levels can be restricted.

However, when using the conventional adaptive array antenna device using P■ in a radio wave environment where the signal wave level is higher than the interference wave level, as shown in Figure 6(a),
As shown in b), there was a drawback that the signal waves were suppressed, making it impossible to secure communications.

(Problems to be Solved by the Invention) As described above, in the conventional adaptive array antenna device using PI, in an environment where interference waves stronger than the signal waves exist, it is difficult to suppress the interference waves and extract the signal waves. However, if it is used in a radio wave environment where the signal wave level is higher than the interference wave level, the signal wave will be suppressed, making it impossible to secure communication.

This invention was made to solve the above problems, and an object thereof is to provide an adaptive array antenna device that can ensure communication by making the signal wave level higher than the interference wave level under any radio wave environment. shall be.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, an adaptive array antenna device according to the present invention includes first and second array antennas that receive incoming radio waves, and power inversion correlation processing means for inputting each received signal and performing power inversion correlation processing, and detecting signal waves for the output of this means and the reception output of either one of the first and second array antennas. Comparison/determination means for detecting the level of the interference wave and comparing and determining its magnitude; and a signal switching means for selectively deriving one of the received outputs.

(Function) In the adaptive array antenna device having the above configuration, the received signal before and after power inversion correlation processing is detected, the signal wave is detected, the level with respect to the interference wave is detected, the magnitude is compared and determined, and the received signal of the larger one is detected. automatically selected and output. When the received wave is greater than the signal wave level > the interference wave level, the received signal before correlation processing is output,
When the interference wave level>signal wave level, a received signal after correlation processing in which interference waves are suppressed is output.

(Embodiment) Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 to 3.

FIG. 1 shows its configuration, where 11 is a main array antenna and 12 is an auxiliary array antenna. The received signals of each array antenna 11.12 are transmitted to a frequency converter 13.
After being converted to an intermediate frequency at 14, the IF amplifier 15.16
The signal is amplified and supplied to the weight control circuit 17. Further, the received signal on the side of the auxiliary array antenna 12 is supplied to a correlation processing circuit 18, a signal switching path 19, and a switching control circuit 20.

The weight control circuit 17 weights each input signal according to the control signal from the correlation processing circuit 18 and outputs the mixed signal.The output signal is supplied to the correlation processing circuit 18 and is also used as a PI system for signal switching. It is supplied to the circuit 19 and the switching control circuit 20. The correlation processing circuit 18 connects the output signal (through system) of the IF amplifier 16 and the weight control circuit 17.
The output signal (PI system) is input, power inversion correlation processing is performed, and the weight amount of the weight control circuit 17 is determined according to the processing result.

The switching control circuit 20 includes a PI type detection circuit 201 and a signal level detection circuit 202, a through type detection circuit 203 and a signal level detection circuit 204, and a comparison judgment circuit 20.
Consists of 5. Detection circuits 201 and 203 each detect demodulated data from input received signals. The signal level detection circuits 202 and 204 are each composed of a matched filter, and the corresponding detection circuits 201 and 204 are configured with matched filters.
The S/J level of the demodulated data obtained in step 203 is detected. A comparison/judgment circuit 205 compares the S/J level of each demodulated data obtained from the through system and the PI system to determine the magnitude thereof, and according to the determination result, the signal switching circuit 2
0 switching control.

The operation of the above configuration will be described below with reference to FIGS. 2 and 3.

The signal waves and interference waves received by the main antenna 11 and the auxiliary antenna 12 are frequency-converted to intermediate frequencies by frequency converters 13-14, amplified by IF amplifiers 15-16, and then sent to a weight control circuit 17. Supplied. Further, the signal on the side of the auxiliary antenna 12 is supplied as a through system to the correlation processing circuit 18, the signal switching circuit 19, and the switching control circuit 20. Weight control circuit 17 and correlation processing circuit 18
Then, the input signal is subjected to PII-related processing, and the level of either the signal wave or the interference wave, whichever is stronger, is suppressed and is supplied as a PI system to the signal switching circuit 19 and the switching control circuit 20.

Here, in the radio waves arriving at each antenna 11.12,
When the level of the interference wave J is higher than that of the signal wave S, the received signal of the through system becomes as shown in Fig. 2 (a), and the PI
The received signal of the system has the interference wave J suppressed by PI processing, and becomes as shown in FIG. 2(b). The demodulated data of the received signal from each prefecture is detected by the detection circuits 201 and 203, and the S/J of the demodulated data is detected by the signal level detection circuits 202 and 204.
The level is detected, and the comparison/judgment circuit 205
J levels are compared. At this time, since it is determined that the PI system is larger, the signal switching circuit 19 is controlled to switch to the PI system. Therefore, as shown in FIG. 2(c), the PII received signal in which the interference wave J is suppressed is selectively output.

Conversely, when the level of the signal wave S is higher than that of the interference wave J, the received signal of the through system becomes as shown in Fig. 3(a), and the received signal of the PI system becomes the signal wave S due to PI processing. It is suppressed as shown in FIG. 3(b). Similar to above,
In the switching control circuit 20, the S/ of each demodulated data of both systems is
When comparing the J levels, it is determined that the through type is higher. Therefore, the signal switching circuit 19 is controlled to switch to the through system side. Therefore, as shown in FIG. 3(C), a through-system received signal in which the signal wave S is larger than the interference wave J is selectively output.

Therefore, the adaptive array antenna device with the above configuration suppresses the through system in a radio wave environment where the signal wave S is larger than the interference wave J, and suppresses the interference wave J by PI processing in a radio wave environment where the interference wave J is larger than the signal wave S. Since the PI system is automatically selected and output, stable communication can be ensured in any environment.

[Effects of the Invention] As described above, according to the present invention, it is possible to provide an adaptive array antenna device that can ensure communication by making the signal wave level higher than the interference wave level under any radio wave environment.

[Brief explanation of the drawing]

FIG. 1 is a block circuit diagram showing an embodiment of the adaptive array antenna device according to the present invention, FIGS. 2 and 3 are waveform diagrams for explaining the operation of the embodiment, and FIG. 4 is a block circuit diagram showing an embodiment of the adaptive array antenna device according to the present invention. A characteristic diagram for explaining the power inversion correlation process used, and FIGS. 5 and 6 are waveform diagrams for explaining the operation and drawbacks of the conventional device. 11... Main array antenna, 12... Auxiliary array antenna, 13.14... Frequency converter, 15.18.
・・IF amplifier, 17・・Weight control circuit, 18・
...Correlation processing circuit, 19...Signal switching circuit, 20...
・Switching control circuit, 201... PII detection circuit, 202
...PI system double signal level detection circuit 203...Through system detection circuit, 204...Through system signal level detection circuit, 205...Comparison judgment circuit. Applicant's representative Patent attorney Takehiko Suzue (a) (a) 4rIA (b) (C) Figure (b) (c) Figure 3 (a) (b) Figure 6

Claims (1)

[Claims] first and second array antennas that receive incoming radio waves;
power inversion correlation processing means for inputting each received signal of these array antennas and performing power inversion correlation processing; a comparison/judgment means for detecting a wave, detecting a level with respect to the interference wave, and comparing and determining the magnitude thereof; and an output of the power inversion correlation processing means and the first and second arrays based on the determination result of this means. An adaptive array antenna device comprising: signal switching means for selectively deriving one of the reception outputs of one of the antennas.