JPH02280083A - Measuring instrument for water vapor content and rainfall quantity - Google Patents

Abstract

PURPOSE:To easily measure the water vapor content and the rainfall quantity in a propagation path by constituting this instrument of a transmitter for transmitting a reference signal and a short millimeter wave band signal, and a receiver for receiving these signals and measuring its phase difference and receiving level variation. CONSTITUTION:A signal of a local oscillator 223 is mixed with a reference signal by a mixer 221 and converted to a reference intermediate frequency signal by a frequency converter 22, and in the same way, a signal of the local oscillator 223 is multiplied by a multiplier 224 and thereafter mixed with a short millimeter wave band signal by a mixer 222 for short millimeter wave band signal and converted to a short millimeter wave intermediate frequency signal. Subsequently, each intermediate frequency signal of the reference signal and the short millimeter wave band signal which are brought to frequency conversion by the frequency converter 22 to the same frequency is brought to phase comparison and detection of a receiving level in a phase comparison/level detector 23. In a display part 24, the water vapor content and the rainfall quantity are calculated respectively by executing a prescribed operation based on these result of phase comparison and variation of the receiving level and they are displayed.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a device that measures the amount of water vapor and rainfall in a propagation path using the propagation characteristics of electromagnetic waves in the microwave, millimeter wave, and short millimeter wave bands. .

[Conventional technology]

Generally, in wireless communication systems that use high frequencies such as microwaves, water vapor and rain in the transmission path affect the propagation of radio waves. Therefore, it is required to measure the amount of water vapor and rainfall in the transmission line.

Conventionally, as this type of water vapor/rainfall measuring device, a device has been proposed in which a hygrometer or a rain gauge is placed in a transmission line, the amount of water vapor is calculated from the measured humidity, and the rainfall is directly determined from the rain gauge.

[Problem to be solved by the invention]

Since the above-described conventional hygrometer and rain gauge devices are each configured as an independent measuring device, two 4 (11) meters are required to measure humidity and rainfall.

Furthermore, in order to measure the amount of water vapor and rainfall over a wide area, it is necessary to install a large number of measuring instruments, which poses a problem that measurement is troublesome and expensive.

An object of the present invention is to provide a water vapor amount/rainfall measuring device that can easily measure water vapor amount and rainfall amount.

[Means to solve the problem]

The water vapor amount/rain amount measuring device of the present invention is composed of a transmitter and a receiver that are arranged opposite to each other in a signal propagation path.
The transmitter includes a reference signal generator that generates a microwave or millimeter wave band signal, a multiplier that multiplies the generated reference signal into a short millimeter wave band signal, and a multiplier that multiplies these reference signals and short millimeter wave band signals, respectively. The receiver includes an antenna that receives the reference signal and the short millimeter wave band signal, respectively, a frequency converter that converts the frequency of each received signal, and a frequency converter that compares the phase difference of each signal. In addition, it is equipped with a phase comparison/level detector that detects the received level of the reference signal, and a display that calculates and displays the amount of water vapor and rainfall based on the phase difference between the two signals and the decrease in the received level. .

[Operation] With this configuration, by measuring the phase difference and reception level change between the reference signal and the short millimeter wave band signal for the amount of water vapor and the amount of rain, respectively, it becomes possible to measure the amount of water vapor and the amount of rain simultaneously.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a functional block diagram showing one embodiment of the present invention. (a) of the same figure shows a transmitter, and a transmitter 1 constituting this transmitter transmits a microwave or millimeter wave band reference signal (
The reference signal generator 11 generates a reference signal (fo).

One of the reference signals output from the reference signal generator 11 is transmitted as is from the antenna 13A. The frequency of the other signal is multiplied by 1 through a multiplier 12 that generates harmonics of the reference signal, and the signal is sent to the antenna 13 as a short millimeter wave band signal.
Sent from B.

FIG. 2B shows a receiving section, and the receiver 2 constituting this receiving section has antennas 2LA and 21B that receive the reference signal and the short millimeter wave band signal, respectively. It has a frequency converter 22 that converts the frequency of the signal inputted from the input signal, a phase comparison/level detector 23 that compares the phase and level of the frequency-converted signal, and a display 24 that displays the amount of water vapor and the amount of rain. ing.

The frequency converter 22 includes a reference signal mixer 221, a short millimeter wave band signal mixer 2223, a local oscillator 223. A short millimeter wave band local oscillation signal multiplier 224° and a reference intermediate frequency signal multiplier 225 are provided. In this frequency converter 22, the signal from the local oscillator 223 is mixed with a reference signal by a mixer 221 to convert it into a reference intermediate frequency signal, and similarly, the signal from the local oscillator 223 is multiplied by a multiplier 224 and then converted into a short millimeter frequency signal. A band signal mixer 222 mixes it with a short millimeter wave band signal and converts it into a similar millimeter wave intermediate frequency signal. Further, the reference intermediate frequency signal is multiplied by a reference intermediate frequency signal multiplier 225.

Then, the intermediate frequency signals of the reference signal and the short millimeter wave band signal, which have been frequency-converted to have the same frequency by the frequency converter 22, are subjected to phase comparison and reception level detection in the phase comparison/level detector 23, respectively. .

The display unit 24 calculates the amount of water vapor and the amount of rain by performing predetermined calculations based on these phase comparison results and the change in reception level, and displays the calculated amounts.

That is, the phase of the short millimeter wave signal is changed according to the amount of water vapor in the propagation path, but the phase of the reference signal is hardly changed even by water vapor. Therefore, by determining the phase difference between both signals, it is possible to measure the amount of water vapor in the propagation path.

In addition, since the reception level of the reference signal changes due to rain (the reference signal is set in advance to a frequency with such characteristics), it is possible to measure the amount of rainfall by determining the change in this reception level. I can do it.

[Effects of the Invention] As explained above, the present invention includes a transmitter that transmits a reference signal and a short millimeter wave band signal, and a receiver that receives these signals and measures the phase difference and reception level change. By using the phase difference between the reference signal and the short millimeter wave band signal and the received level change for the amount of water vapor and rainfall, it is possible to easily measure the amount of water vapor and rainfall in the propagation path.

[Brief explanation of drawings]

FIG. 1 is a functional block diagram of an embodiment of the present invention, in which (a) shows a transmitting section and (b) shows a receiving section. DESCRIPTION OF SYMBOLS 1... Transmitter, 2... Receiver, 11... Reference signal generator, 12... Multiplier, 13A, 13B... Antenna, 21A, 21B... Antenna, 22... Frequency converter, 23... phase comparison/level detection section, 24.
...Display section, 221... Reference signal mixer, 222.
... Mixer for short millimeter wave band signals, 223... Local oscillator, 224... Multiplier for short millimeter wave band local oscillation signals, 225.
・Multiplier for reference intermediate frequency signal.

Claims (1)

[Claims] 1. A transmitter and a receiver are arranged opposite to each other in a signal propagation path, and the transmitter includes a reference signal generator that generates a microwave or millimeter wave band signal, and a reference signal generator that generates a signal in the microwave or millimeter wave band. A multiplier that multiplies short millimeter wave band signals, and an antenna that transmits these reference signals and short millimeter wave band signals, respectively.
The receiver includes an antenna that receives the reference signal and the short millimeter wave band signal, a frequency converter that matches the frequencies of each received signal, and a frequency converter that compares the phase difference between each signal and determines the reception level of the reference signal. A phase comparison/level detector to detect,
What is claimed is: 1. A water vapor amount/rainfall measurement device comprising: a display device that calculates water vapor amount and rainfall amount based on a phase difference between both signals and a decrease in reception level and displays the amounts.