JPH01143404A - Electronic scanning antenna - Google Patents

Abstract

PURPOSE:To obtain an excellent relation of communication while the state tracking and acquiring the opposite party by constituting the antenna so that all transient phenomena of a pulse signal driving each phase shifter are not overlapped. CONSTITUTION:Many antenna elements 11, 12...1n are arranged as an array and variable phase shifters 21, 22...2n are connected respectively to the antenna elements. A signal distribution synthesizer 3 is connected in common to the variable phase shifters and then connected to the communication equipment main body. A 2nd and succeeding delay times of delay lines 41, 42...4n corresponding to each phase shifter are set so as to be deviated by a time (t) and the resulting time is fed to the corresponding variable phase shifter. The presence of the time (t) causes the transient phenomenon of a radar beam at pulse drive to be avoided and the phase discontinuity or noise at FM or PM communication is reduced remarkably.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) This invention relates to an improvement in an electronic scanning antenna that electronically changes the beam scanning direction.

(Prior Art) Electronic scanning antennas have traditionally scanned a target object by electronically scanning a beam across a wide space at extremely high speeds while the antenna is mechanically stationary, such as in active phased array radar devices. used for catching. As shown in Fig. 4, a conventional electronic scanning antenna has a large number of antenna elements (11), (12), .
21)(22)...(2n) are connected in correspondence. In addition, each of these phase shifters has a common signal combining/distributing device (3
) and a beam controller (4) that derives a phase shifter control pulse signal in accordance with beam switching. By the way, since the main purpose of conventional radar equipment has been to quickly search for and track targets, for example, the waveform of the control pulse signal (I
IP) As shown in (12P)...(13P),
It was necessary for the beam controller (4) to change the setting bits in each phase shifter at a speed (beam switching period TL) on the nanosecond or microsecond level.

However, recently, electronic scanning antennas have come to be used not only for radar purposes, but also for communication purposes for communicating and exchanging information with other parties. For example, frequency modulation (
Various types of information are exchanged using FM (FM) waves or phase modulated (PM) waves, but transient phenomena of the phase shifter control pulse signal pose a problem.

In other words, in conventional electronic scanning antennas, transient phenomena at the rise of each control pulse signal occur almost simultaneously, and although there was no problem when simply detecting the presence or absence of a target, this is not a problem for signals that handle the transmission and reception of information. Among them, a drawback occurred in that the signal was superimposed on the output side of the signal combiner/distributor (3) and appeared as noise or phase discontinuity.

(Problems to be Solved by the Invention) The present invention aims to reduce the influence of transient phenomena of the phase shifter control pulse signal during communication in an electronic scanning antenna having the function of communicating with a target as described above. The purpose is to be able to effectively track and communicate with a target.

[Structure of the invention]

(Means for Solving the Problems) In the electronic scanning antenna of the present invention, a plurality of antenna elements are connected to a signal combining/distributing circuit via phase shifters, and each phase shifter is connected to a signal combining/distributing circuit via a phase shifter. The beam controller is provided with a beam controller that derives a phase shifter control pulse signal with a time difference so that the rise times of the pulse signals supplied to and driven by the phase shifter do not all have the same timing.

(Function) In the electronic scanning antenna of the present invention, the control pulse signals that control the phase shifter are made so that the rising timings are not exactly the same, so there is no noise or phase difference in the transmitted/received signals with the target partner. Discontinuities are significantly reduced.

(Embodiments) Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a configuration diagram showing an embodiment of an electronic scanning antenna according to the present invention. In FIG. 1, a large number of antenna elements (11), (12), ... (in) are arranged in an array, and these antenna elements are provided with variable phase shifters (21
)(22)...(2n) are connected, respectively. The variable phase shifters are commonly connected to a signal distributing/combining device (3), and the signal combining/distributing device (3) is connected to a main body of a communication (transmission/reception) device (not shown). The signal combiner/distributor (3) distributes and supplies the signal from the transmitter main body side to each of the phase shifters in a so-called tournament feed type or series feed type, and also combines the received signals from each phase shifter and sends it to the receiver main body. Transmit. A beam controller (4) is connected to the variable phase shifter to derive and supply a control pulse signal to selectively control these and obtain necessary beam directivity characteristics. The beam controller (4) is composed of, for example, a control pulse signal generator (4a) and a delay circuit (4b) for delaying the pulse signal from the control pulse signal generator (4a).

The delay circuit (4b) includes each of the phase shifters (21), (22), and
・Each delay line (41) (42) corresponding to (2n)・
...(4n).

If this electronic scanning antenna also has the function of transmitting and receiving data to and from a target, the beam scanning speed does not need to be that fast. There is no problem even if the set time T is about 0.1 seconds.

Therefore, each delay line (41) (42) corresponding to each phase shifter
)...(4n) are set so as to be sequentially shifted by time t from the second time onwards, and are supplied to the corresponding variable phase shifters. The existence of the delay time t avoids superimposition of transient phenomena during pulse drive of the radar beam, and noise or phase discontinuity during FM or PM communication is significantly reduced.

In Fig. 2, all of the phase shifters corresponding to each antenna element have a delay time difference of time t to prevent overlap during control, but depending on the degree of influence of transient phenomena, for example, Fig. 3 As shown in the waveform diagram shown in FIG. 2, a delay time difference t may be given to each unit of a plurality of antenna elements divided into several groups, such as three.

Furthermore, the fact that the control signal from the beam controller is not superimposed has the advantage that the peak power during control is reduced accordingly.

〔Effect of the invention〕

As explained above, the electronic scanning antenna of the present invention is configured so that the transient phenomena of the pulse signals that drive each phase shifter do not overlap, so that it can track the other party and maintain the captured state. It becomes possible to obtain a good communication relationship.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of an electronic scanning antenna according to the present invention, FIG. 2 is a waveform diagram showing the pulse signal derived from the beam controller in the block diagram shown in FIG. 1, and FIG. A waveform diagram showing a pulse signal derived from the beam controller in another embodiment of the present invention, FIG. 4 is a configuration diagram showing a conventional electronic scanning antenna, and FIG. 5 is a waveform diagram showing a pulse signal derived from the beam controller in FIG. FIG. 2 is a waveform diagram showing a pulse signal. (11) (12)...(in): Antenna element (21) (22)...(2n): Phase shifter (3):
Signal combiner/distributor (4): Beam controller

Claims (1)

[Claims] A plurality of antenna elements arranged in an array, a plurality of phase shifters connected to each of the plurality of antenna elements, and a signal combining/distributing device commonly connected to the plurality of phase shifters. , a beam controller that is connected to the plurality of phase shifters and derives control pulse signals with a time difference so that the rising timings of the pulse signals controlling each of the phase shifters do not overlap. scanning antenna.