JPH0792252A - Marine radar transmitter - Google Patents

Abstract

(57) [Abstract] [Purpose] To make the transmission pulse width variable. [Structure] The waveform of the transmission trigger (a) is shaped (b), it is differentiated (c), and the level of the pulse width control voltage V _P1 is compared with that of the pulse width control voltage V _P1 as shown in (d). A pulse voltage with a width corresponding to the level is obtained. Pulse width control voltage V
_{Although P1} is input from the indicator, the voltage level of the indicator can be continuously changed manually.
Therefore, the transmission pulse width can be continuously changed. For example, set the radar screen to the medium range,
The pulse width of the transmission pulse can be changed continuously up and down based on the pulse width of the transmission pulse for medium distance, and it can also be changed continuously between the short pulse for short distance and the long pulse for long distance. It is possible to easily and optimally adjust the size of the target on the radar screen.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radar transmitter for ships, and more particularly to improvement of a pulse generator circuit of a modulator for pulse-exciting a transmission tube.

[0002]

2. Description of the Related Art A marine radar is provided with a transmitter as shown in FIG. 3, and a range is divided into, for example, a short range, a medium range and a long range, and a width of a transmission pulse can be changed for each range. In this way, the size of the target displayed on the radar screen is appropriately adjusted.

That is, in FIG. 3, the transmission pulse output from the pulse generation circuit 30 in response to the transmission trigger TI is increased in voltage by the high-voltage pulse generation circuit 3 via the drive circuit 2, and the transmission tube 4 is thereby caused. The pulse wave is transmitted from the antenna 5 by exciting the pulse oscillation, and the pulse generation circuit 30 transmits to the pulse generation circuit 30 a distance range (for example, short range, medium range, long range) manually set by an indicator (not shown). Three
Since the pulse width control voltage V _P2 having a voltage level corresponding to the seed distance range) is given, the pulse generation circuit 30 uses the transmission pulse having the width corresponding to the voltage level of the pulse width control voltage V _P2 as the transmission trigger TI. A radio wave having a pulse width corresponding to a distance range manually set by the indicator is transmitted in response to the transmission.

The conventional pulse generating circuit 30 includes, for example, a rectangular wave oscillator, a frequency divider for dividing the output of the rectangular wave oscillator, and a frequency division output according to the voltage level of the pulse width control voltage V _P2 . And a selection circuit that performs selection in response to a transmission trigger TI.

[0005]

As described above, in the conventional marine radar, the radar range is roughly divided into, for example, three divisions, and one predetermined width transmission pulse is assigned to each divided distance range. However, when observing the target on the radar screen, it is difficult to adjust the displayed target to the optimum size because the transmission pulse width can only be changed in stages. There is a problem that is.

The present invention has been made in view of the above problems, and an object thereof is to provide a radar transmitter for a ship capable of continuously changing a transmission pulse width.

[0007]

In order to achieve the above-mentioned object, the radar transmitter for ships of the present invention has the following structure. That is, the marine radar transmitter of the present invention is a marine radar transmitter that generates and transmits a transmission pulse having a width corresponding to the voltage level of the pulse width control voltage given from the indicator; The voltage level of the pulse width control voltage provided from the machine can be continuously changed by manual operation; and a pulse generation circuit that generates a transmission pulse in response to a transmission trigger and a circuit that differentiates the transmission trigger. A circuit that outputs a transmission pulse having a width corresponding to the voltage level of the pulse width control voltage by comparing the levels of the differential signal voltage and the continuously variable pulse width control voltage; To do.

[0008]

Next, the operation of the radar transmitter for ships of the present invention constructed as described above will be described. In the present invention, the pulse width control voltage given from the indicator to the pulse generating circuit is such that its voltage level can be continuously varied by manual operation, and the pulse generating circuit is the differential signal voltage obtained by differentiating the transmission trigger and the continuous signal voltage. The transmission pulse having a width corresponding to the voltage level of the pulse width control voltage is output by comparing the level with the pulse width control voltage that is variable.

As a result, the transmission pulse width can be continuously changed by the manual operation of the indicator, so that the target displayed on the radar screen can be easily adjusted to the optimum size.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a marine radar transmitter according to an embodiment of the present invention. In FIG. 1, this radar transmitter is the same as the conventional one after the driving circuit 2, but the pulse generating circuit 1 has a configuration different from the conventional one.

In the pulse generation circuit 1, the transmission trigger TI
(FIG. 2 (a)) is waveform-shaped by the waveform shaping circuit (Tr1, Tr2) (FIG. 2 (b)), which is then differentiated (C, R).
2C to obtain a differential signal as shown in FIG. 2C, and the comparator 7 compares this differential signal with the pulse width control voltage V _P1 from the indicator as shown in FIG. 2D. Then, a transmission pulse having a width corresponding to the voltage level of the pulse width control voltage V _P1 is formed.

The high-voltage pulse generation circuit 3 includes a pulse transformer T and an F connected in series to the primary side of the pulse transformer T.
It is composed of Tr5 which is an ET switch.

In this high-voltage pulse generation circuit 3, Tr5
However, the output pulse voltage of the pulse generation circuit 1 is applied to its gate through the drive circuit (Tr3, Tr4) 2 to perform an on / off operation to generate a high-voltage pulse voltage on the secondary side of the pulse transformer T.

The transmission tube 4 is connected to the secondary side of the pulse transformer T, oscillates in pulses by a high-voltage pulse voltage, and pulsed radio waves are transmitted from the antenna 5 as in the conventional case.

Here, in the pointing device, the distance range of the radar screen can be set in three steps, for example, a short distance range, a medium distance range, and a long distance range as in the conventional case, but the pulse width given to the pulse generation circuit 1 is set. The control voltage V _P1 is such that its voltage level can be continuously varied by manual operation within the set distance range.

As shown in FIG. 2D, in the comparator 7,
Since the pulse width control voltage V _P1 generates a pulse voltage having a width at the position where the differential signal waveform is sliced, if the voltage level of the pulse width control voltage V _P1 is continuously changed, the slice width is continuously changed accordingly. It is possible to generate a pulse voltage that changes and the pulse width changes continuously.

Therefore, the radar screen can be set to, for example, the medium-range range, and the pulse width of the transmission pulse can be continuously changed up and down with reference to the pulse width of the transmission pulse for the medium range. It is possible to continuously change between the pulse and the long pulse for long distance, and the size of the target on the radar screen can be easily adjusted to the optimum.

[0018]

As described above, the marine radar transmitter according to the present invention enables the pulse width control voltage given from the indicator to the pulse generating circuit to be continuously variable in its voltage level by manual operation. The pulse generation circuit outputs a transmission pulse having a width corresponding to the voltage level of the pulse width control voltage by comparing the level of the differential signal voltage obtained by differentiating the transmission trigger and the continuously variable pulse width control voltage. Therefore, there is an effect that it becomes easy to optimally adjust the size of the target object displayed on the radar screen.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a radar transmitter for a ship according to an embodiment of the present invention.

FIG. 2 is an operation waveform diagram of the pulse generation circuit of the present invention,
(A) is a waveform diagram of an input transmission trigger, (b) is a waveform diagram of a transmission trigger after waveform shaping, (c) is an output waveform diagram of a differentiating circuit, and (d) is an input / output waveform diagram of a comparator. .

FIG. 3 is a general configuration block diagram of a marine radar transmitter.

[Explanation of symbols]

1 pulse generation circuit 2 drive circuit 3 high voltage pulse generation circuit 4 transmission tube 5 antenna 7 comparator C capacitor R resistance T pulse transformer TI transmission trigger Tr1 to Tr5 transistor V _P1 pulse width control voltage

Claims (1)

[Claims] 1. A marine radar transmitter for generating and transmitting a transmission pulse having a width corresponding to a voltage level of a pulse width control voltage given from an indicator, in response to a transmission trigger.
The voltage level of the pulse width control voltage given from the indicator can be continuously changed by manual operation. At the same time, a circuit for differentiating the transmission trigger by a pulse generation circuit for generating a transmission pulse in response to the transmission trigger. And a circuit for outputting a transmission pulse having a width corresponding to the voltage level of the pulse width control voltage by comparing the levels of the differential signal voltage and the continuously variable pulse width control voltage. And a radar transmitter for ships.