JPH02121416A - Phase synthesizing system - Google Patents

Abstract

PURPOSE:To use only one reception antenna for the system and to reduce in space required for the antenna installation location by using signals of upper and lower side bands of the local oscillation frequency as 1st and 2nd transmission signals, respectively, after the conversion of the transmission frequency. CONSTITUTION:An intermediate frequency signal inputted to a transmitter input terminal 1 is branched into two by a distributer 2 and the signal is frequency-converted into signals of upper and a lower side bands of the local oscillation signal from a transmission local oscillator 10 at transmission frequency converters 4, 5. Then the high frequency and the low frequency signals are selected by 1st and 2nd band pass filters 8, 9 and the result is sent to space. The signal is received by a reception antenna 14, passes through a circulator 15, the signal component with the low frequency is a 1st reception signal and the component with the high frequency is reflected totally in the circulator 15, the high frequency component is selected via a circulator 16 and a band pass filter 18 and becomes a 2nd reception signal. Since one reception antenna is enough, the installation at a narrow space is attained while keeping a high transmission characteristic.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a phase synthesis method in heterogain wireless communication, and more particularly to a method for phase-synthesizing radio signals spatially propagated between different layer waves at an intermediate frequency.

[Prior art] Conventionally, in this type of phase synthesis method, one transmission signal is divided into two
A space diversity phase synthesis method is adopted in which signals are received by two or more antennas, each received signal is frequency-converted to an intermediate frequency, and then phase-combined.

[Problem to be solved 1 The conventional space diversity phase synthesis method described above is
The influence of fading can be reduced and higher reliability can be obtained compared to single reception.

However, since two or more antennas are required to receive one transmitted signal, there are problems in that it is difficult to secure a place to install the antennas and the cost of equipment increases.

The present invention has been made in view of the above-mentioned problems, and after converting the transmission frequency, two signals generated above and below the local oscillation frequency are converted to the first and second signals. It is an object of the present invention to provide a phase combining system that can obtain transmission characteristics equivalent to or better than the conventional diversity phase combining system using one receiving antenna by using i2 transmission signals.

[Means for Solving the Problems] In order to achieve the above object, the present invention splits an input intermediate frequency signal into two by a splitter in a heterodyne radio device, and converts each signal into first and second frequency signals. After converting the frequency above or below the same local oscillation frequency and amplifying it, a first bandpass filter selects a signal with a lower frequency among the signals frequency-converted by the first frequency converter. 1 transmission signal, and a signal with a higher frequency among the signals frequency-converted by the second frequency converter is selected by a second bandpass filter and used as a second transmission signal, and these first . The second transmission signal is transmitted from the transmission antenna. After the second transmission signal is received by one reception antenna, the high frequency signal and the low frequency signal are respectively selected by a filter to become the first and second reception signals, and then the respective reception signals are used as the first and second reception signals. ．． The first receiving frequency converter is the second receiving frequency converter. frequency converted to a second intermediate frequency signal, and then these first . This method uses a phase synthesizer to phase synthesize the second intermediate frequency signal.

[Examples] Examples of the present invention will be described below with reference to the drawings.

FIG. 1 shows a block diagram for explaining a phase synthesis method according to an embodiment of the present invention. In FIG. 1, l is a transmitter input terminal, 2.3 is a distributor, and 4.5 is a transmission frequency conversion terminal. 6.7 is a power amplifier, 8.9 is a bandpass filter, 10 is a transmitting local oscillator, 11.12 is a circulator, 13 is a transmitting antenna, 14 is a receiving antenna, 15.16 is a circulator, 17.18 is a A bandpass filter, 19.20 a receiving frequency converter, and 21 a receiving local oscillator.

22 is a distributor, 23 is a phase synthesizer, and 24 is a receiver output terminal.

FIG. 2 is a drawing showing the state of each part until the transmitter input signal is output from the receiver. The present phase synthesis method will be explained as follows based on FIG. 2.

That is, the intermediate frequency signal input to the transmitter input terminal 1 (FIG. 2(a)) is split into two by the 1-divider 2, and then split into two from the transmitting local oscillator lO by the transmitting frequency converters 4 and 5, respectively. It is mixed with the local oscillation signal of the two local oscillation signals and sent out after being frequency-converted above and below the two local oscillation signals (Figure 2 (b)
)), this output signal is amplified by a power amplifier 6.7, respectively, and the first . A high frequency signal and a low frequency signal are respectively selected by a second bandpass filter 8.9 and sent into space by a transmitting antenna 13 via a circulator 11.12.

This signal is received by the receiving antenna 14. After passing through the circulator 15, only the low frequency signal components are selected by the first circulator 15 and become the first received signal (Fig. 2 (C)).On the other hand, after passing through the circulator 15, the high frequency components are selected. It is totally reflected by the circulator 15 of the tube 1, passes through the circulator 16, and is input to the second bandpass filter 18. As a result, the high frequency component is selected and becomes the second received signal (FIG. 2(e)).

The first and second received signals are connected to the first and second received signals, respectively.
is input to the receiving frequency converter 19, 20 of the receiving local oscillator 21, mixed with the local oscillation signal of the receiving local oscillator 21, and the first and second
becomes an intermediate frequency signal. Here, by setting the receiving local oscillation signal frequency to the same frequency as the transmitting local oscillation signal frequency, both the first and second intermediate frequency signals are exactly the same as the intermediate frequency signal input to the transmitter. (Figure 2 (d), (f)) Therefore, by in-phase combining these first and second intermediate frequency signals, it is possible to obtain the same effect as the conventional space diversity phase combination method. .

Furthermore, as shown in FIG. 3, even if one of the upper and lower signal components suffers waveform deterioration due to selective fading or the like, in most cases the other signal component remains normal. Therefore, as in the space diversity method, the probability that two received signals will both suffer waveform distortion due to the positional relationship between the two antennas is extremely low.

Note that the present invention is not limited to the above embodiments,
Of course, various modifications can be made within the scope of the gist.

[Effects of the Invention] As explained above, the present invention can obtain transmission characteristics with one receiving antenna that are equivalent to or better than the space diversity phase combining method that uses two antennas. This has the effect of making it possible to install in a smaller space and reducing installation costs.

[Brief explanation of drawings]

Fig. 1 is a block diagram for explaining the present invention in detail, Fig. 2 is a diagram showing the state of each part until the transmitter input signal is output from the receiver, and Fig. 3 is a waveform distortion caused by selective fading. FIG. 3 is a diagram showing a receiving antenna input signal when a signal is generated. 2.3=Distributor 4.5: Transmission frequency converter 6.7: Power amplifier 8.9: Bandpass filter lO: Transmission local oscillator 11.12: Circulator 13: Transmission antenna 14: Reception antenna 15.16: Circulator 17, 18: Bandpass filter 19.20: Reception frequency converter 21: Reception local oscillator 22: Divider 23: Phase synthesizer

Claims (1)

[Claims] In a heterodyne radio device, an input intermediate frequency signal is split into two by a divider, and each signal is divided into a first signal and a second signal.
After converting the frequency above and below the same local oscillation frequency using a frequency converter and amplifying the frequency, a signal with a lower frequency among the signals frequency-converted by the first frequency converter is selected by a first bandpass filter. as the first transmission signal, and
Among the signals frequency-converted by the second frequency converter, a high-frequency signal is selected by a second bandpass filter as a second transmission signal, and these first and second transmission signals are transmitted to the transmission antenna. On the other hand, after the first and second transmission signals are received by one receiving antenna, a high frequency signal and a low frequency signal are respectively selected by a filter and the first and second received signals are transmitted. Then, each received signal is frequency-converted into first and second intermediate frequency signals by first and second reception frequency converters, and then these first and second intermediate frequency signals are phase-converted by a phase synthesizer. A phase synthesis method characterized by compositing