JPH03211484A - Transmission system for radar antenna azimuth angle information - Google Patents

Abstract

PURPOSE:To perform transmission without occupying a wide area newly and to make a display while the influence of jitters is reduced by transmitting the azimuth angle information not independently of a reflected video signal, but together the reflected video signal by time-base multiplexing. CONSTITUTION:The signal from the rotary shaft of a radar antenna which is obtained by a shaft encoder 1 is supplied to an ACP/ARP generating circuit to obtain the azimuth angle information, which is supplied to a latch circuit 11. The circuit 11 reads in this information in the free time set between the radio wave transmission timing of the radar antenna and next timing by a radar system trigger and multiplexed with the time basis between the reflected video signal at the timing of a synthesizing circuit 12 and the signal at the next timing and transmitted as a radio wave. On a reception side, the azimuth angle information separated from the video signal by a separating circuit 13 is locked to the phase of an oscillator 15 under the frequency division rate control of a circuit 6 and then led out after the jitters are suppressed sufficiently by a PLL circuit 14.

Description

[Detailed Description of the Invention] [Summary] Regarding a method for transmitting high-speed rotation, high-resolution radar antenna azimuth information using a wireless line, the present invention is a new method for transmitting without monopolizing a wide band and reducing the influence of jitter. a combining transmitting means for time-axis multiplexing and transmitting the azimuth information between the reflected video signal timings for the purpose of display; a separating means for separating the time-axis multiplexed azimuth information and the reflected video signal; Jitter suppressing means extracts the azimuth angle information by suppressing jitter in one circuit.

[Industrial Application Field] The present invention relates to a system for transmitting high-speed rotating, high-resolution radar antenna azimuth information using a wireless line.

There is a system that uses a radar antenna to detect the position of a moving object, such as an aircraft, and displays this on a display to monitor the moving object. In this case, there is a method in which the azimuth angle information from the radar antenna is transmitted by radio waves using a wireless line, and the receiving side receives this information and inputs it to the display.In this case, the radio waves are effectively used without monopolizing a wide band. and must be displayed without the influence of jitter.

[Conventional technology]

FIG. 3 shows a block diagram of a conventional example. In the figure, a signal from the rotary shaft of the radar antenna obtained by a shaft encoder 1 is converted into 6-position angle information by an eight CP/ARP generator circuit 2. This azimuth angle information is A CP (
azimuth change pulse) signal (pulse signal with one pulse per rotation of the radar antenna) and A RP (azimuth change pulse) signal (a pulse signal with one pulse per revolution of the radar antenna)
(pulse) signal (consists of a pulse signal with one pulse per revolution of the radar antenna.Azimuth information is modulated by a group band modem 3 with a width of 48 KHz, for example.
is transmitted by radio waves using a wireless line, and the receiving side receives 4
It is demodulated by the group band modem 4 of 8KHzlLA.

On the other hand, the reflected video signal (for example, 1.5 MHz width) obtained by receiving the radar antenna is transmitted by radio waves using a wireless link, and is supplied to the display device 5 on the receiving side together with demodulated azimuth information. Displayed for each azimuth.

The reason why group band modem 3.4 (relatively wide band, such as 48 KHz width) is used for transmission is that a relatively wide band is required to obtain high-resolution azimuth information, and general telephone channels ( Jitter occurs in transmission over a wireless line using a 3KHz width), and the jitter that occurs when azimuth information of a wider band than this is transmitted over a transmission channel is PLL (phase 1ocked).
1oop) This is due to the inability to suppress the circuit ri.

[Problem to be solved by the invention]

Conventional examples using group band modem 3.4 transmit azimuth information separately and independently from the reflected video signal, so a new wide band is exclusively used for azimuth information in addition to the band for the reflected video signal. This resulted in a problem that hindered the effectiveness of radio waves.

The present invention newly enables transmission without exclusive use of a wide band, and
An object of the present invention is to provide a radar antenna azimuth information transmission system that can display information with less influence of jitter.

[Means to solve the problem]

FIG. 1 shows a diagram of the principle of the present invention. In the figure, reference numeral 30 denotes a combining transmitting means which time-base multiplexes the azimuth information obtained from the radar antenna between the timings of the reflected video signals obtained from the radar antenna and transmits the multiplexed information.

Reference numeral 31 denotes a separation means that separates the time axis multiplexed azimuth information and the reflected video signal.

32 is a jitter suppression means, which PLs the separated azimuth information.
Jitter is suppressed and extracted using the L circuit.

[Effect]

In the present invention, since the azimuth information is not transmitted independently from the reflected video signal, but is time-axis multiplexed and transmitted on the reflected video signal, the band of the azimuth information appears to be the band of the reflected video signal. Therefore, there is no need to exclusively occupy a new band just for azimuth information.
Radio waves can be used effectively. In this case, the jitter of azimuth information caused by time axis multiplexing is suppressed by the PLL. 9 [Embodiment] FIG. 2 shows a block diagram of an embodiment of the present invention, in which the same components as in FIG. 3 are given the same numbers. For example, the rotation speed of the radar antenna is 15r, p, ■.

When the azimuth resolution is 1/4096 (that is, 4096 pulses/360°), the ACP signal obtained together with the ARP signal in the ACP/ARP generation circuit 10 is 40
96 pulses/one rotation, and this azimuth information is supplied to the latch circuit 11. In the latch circuit 11, the azimuth information is read in the idle time set between the radio wave transmission timing of the radar antenna and the next radio wave transmission timing by the radar system trigger output from the radar device. The azimuth information and the reflected video signal read in this way are supplied to the combining circuit 12, and the azimuth information is time-axis multiplexed between the reflected video signal at one timing and the reflected video signal at the next timing. The azimuth information thus time-axis multiplexed onto the reflected video signal is transmitted by radio waves using a wireless link (for example, a radar video transmission channel with a width of 1.5 MHz), and is sent to a separation circuit on the receiving side. 13. In this case, in the present invention, the azimuth information is not transmitted independently from the reflected video signal as in the conventional example shown in FIG. 3, but is time-axis multiplexed and transmitted on the reflected video signal. Moreover, the band for the azimuth information is included in the band for the reflected video signal, so there is no need to exclusively occupy a new band just for the azimuth information, and radio waves can be used effectively.

The reflected video signal and the azimuth information are separated in the separation circuit 13, and the reflected video signal is supplied to the display device 5, while the azimuth information is supplied to the PLL circuit 14. PLL circuit 1
4, the output of the oscillator 15 is divided by the frequency dividing circuit 16, the signal and the azimuth information are multiplied by the multiplier 17, and the multiplication output is divided by the voltage taken out through the low-pass filter 18. ! By υjulling the frequency division ratio of 116, the azimuth information is locked to the phase of the oscillator 15, and jitter is suppressed by this phase lock. In this case, since the bandwidth of the 11th angle information is narrower than the bandwidth of the radar video transmission channel, the jitter caused by this multiplexing can be sufficiently suppressed by the ItP circuit. Here, the output of the frequency dividing circuit 16 is frequency-divided by the frequency dividing circuit 19 and the ACP signal (4096 pulses/1
rotation), while the output of the frequency dividing circuit 19 is output to the counter 2.
The reference AR is divided by o and sent from the ARP reference setting circuit 21.
The phase of the P signal is compared with the phase comparator 22, and the result is an ARP signal (1 pulse/1 rotation).

[Efficacy of invention Song Dynasty]

As explained above, according to the present invention, since the azimuth information is time-axis multiplexed and transmitted on the reflected video signal, the viewing angle is
t, the band for the azimuth information is included in the band for the reflected video signal, so there is no need to exclusively occupy a new band just for the azimuth information, and radio waves can be used effectively.

[Brief explanation of drawings]

FIG. 1 is a principle diagram of the present invention, FIG. 2 is a block diagram of an embodiment of the present invention, and FIG. 3 is a block diagram of a conventional example. In the figure, 1 is a shaft encoder, 5 is a display, 10 is an ACP/^RP generation circuit, 11 is a latch circuit, 12 is a synthesis circuit, 13 is a separation circuit, 14 is a PLL circuit, 15 is an oscillator, 16.19 is a 17 is a multiplier, 18 is a low-pass filter, 20 is a counter, 21 is an ARP reference setting circuit, 22 is a phase comparator, 30 is a combination transmission means, 31 is a separation means, and 32 is a jitter suppression means. .

Claims (1)

[Scope of Claims] Synthesizing transmission means (30) for time-axis multiplexing and transmitting azimuth information obtained from a radar antenna between reflected video signal timings obtained from the radar antenna, and the time-axis multiplexed azimuth information. It is characterized by comprising a separating means (31) for separating information and a reflected video signal, and a jitter suppressing means (32) for extracting the separated azimuth information by suppressing jitter using a PLL circuit. Radar antenna azimuth information transmission system.