JPS63263834A - Phase synthesizing system - Google Patents

Abstract

PURPOSE:To obtain a transmission characteristic equivalent to or more that of a space diversity phase synthesizing system, by sending a local oscillation frequency after applying frequency conversion on the upper side and the lower side of the oscillation frequency at a transmission frequency converter, and after receiving, applying the frequency conversion on a signal of high frequency and a signal of low frequency, and performing the phase synthesis of them by a phase synthesizer. CONSTITUTION:An intermediate frequency signal inputted to the input terminal 1 of a transmitter is outputted in a state where the frequency conversion are applied on the upper and the lower side of a local oscillation signal at the transmission frequency converter 2, and is emitted to space by a transmission antenna 6 via a band elimination filter 5. A signal received by a receiving antenna 7 is separated to first and second reception signals, and are inputted to first and second receiving frequency converters 12 and 13, respectively, then, they become first and second intermediate frequency signals. By applying in phase synthesis on the first and second intermediate frequency signals, it is possible to obtain the same effect as that of a conventional space diversity phase synthesizing system.

Description

[Detailed Description of the Invention] [Field of Industrial Application] - The present invention relates to a phase synthesis method in heterodyne wireless communication, and in particular, to a method for combining wireless signals spatially propagated at different frequencies.
A method of phase synthesis at an intermediate frequency [Prior art] Conventionally, in this type of phase synthesis method, one transmitted signal is received by two or more antennas, each frequency converted to an intermediate frequency, and then phase synthesis is performed. A space diversity phase synthesis method is adopted.

[Problems to be solved] The conventional space die-hard phase synthesis method described above is
It is possible to reduce the influence of fading and obtain higher reliability compared to medium reception.

However, since two or more antennas are required to receive one transmitted signal, there are problems in securing a place to install the antennas and increasing equipment costs.

The present invention has been made in view of the above-mentioned problems.
By effectively utilizing two signals generated above and below the local oscillation frequency after transmitting frequency conversion, this phase synthesis method enables a single antenna to obtain transmission characteristics equivalent to or better than the conventional diversity phase synthesis method. For the purpose of providing.

Solution to the L Problem] In order to achieve the above object, the phase synthesis method of the present invention converts the input intermediate frequency signal into a transmission frequency converter on the transmitting side to convert the input intermediate frequency signal into upper and lower local oscillation frequencies in a heterodyneless installation. This signal is amplified and sent out from a transmitting antenna as a transmitting signal, and after this transmitting signal is received by one receiving antenna, a high-frequency signal and a low-frequency signal are selected by a filter. Then, the first and second intermediate frequency signals are frequency-converted by first and second reception frequency converters, respectively. This method uses a phase synthesizer to phase synthesize the intermediate frequency signals of .

[Embodiment] FIG. 1 shows an apparatus 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 is a transmitting frequency converter, 3 is a transmitting local oscillator, 4 is a power amplifier, 5 is a band-rejection filter, 6 is a transmitting antenna, 7 is a receiving antenna,
8.9 is a circulator, 10.11 is a first and second bandpass filter, and 12.13 is a first and second reception frequency converter.

14 is a receiving local oscillator, 15 is a distributor, 16 is a phase synthesizer, and 17 is a receiver output terminal.

The present phase synthesis method will be explained as follows with reference to FIGS. 2(a) to 2(f) showing the states of each part until the transmitter input signal is output from the receiver.

That is, the intermediate frequency signal input to the transmitter input terminal l (Fig. 2(a)) is mixed with the local oscillation signal from the transmitting local oscillator 3 in the transmitting frequency converter 2, and the frequency signal above and below the local oscillating signal is mixed. The converted state is output (second
(b)), this output signal is amplified by a power amplifier 4, passed through a band-elimination filter 5, and sent into space by a transmitting antenna 6.

This signal is received by the receiving antenna 7.

After the signal received by the receiving antenna 7 passes through the circulator 8, only the low frequency signal components are selected by the first bandpass filter lO and become the first received signal (FIG. 2(C)). , high frequency components pass through the circulator 8, are totally reflected by the first bandpass filter lO, pass through the circulator 9, and pass through the second bandpass filter 11.
is input. As a result, a signal component with a high frequency is selected by the second bandpass filter and becomes the second received signal (FIG. 2(e)).

The first and second received signals are input to first and second reception frequency converters 12.13, respectively, and mixed with the local oscillation signal of the reception local oscillator 14 to become first and second intermediate frequency signals. . 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)), L 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 combining method.

Further, as shown in FIG. 3, either the upper or lower signal component may undergo waveform deterioration due to selective fading or the like, and in most cases the other signal component becomes normal. Therefore, the probability that waveform distortion will occur in both received signals is extremely low due to the positional relationship of the two antis, as in the Spay-diharsity method.

It goes without saying that the present invention is not limited to the above embodiments, and can be modified in various ways within the scope of the gist.

[Effects of the Invention] As described above, the present invention has the effect of obtaining transmission characteristics equivalent to or better than the space diversity phase combining method using two receiving antennas.

[Brief explanation of the drawing]

FIG. 1 is a device diagram for explaining a phase synthesis method according to an embodiment of the present invention, and FIGS. 2(a) to (f) show that the transmitter input signal is
The figure shows the state of each part until it is output from the receiver. Figure (a) shows the transmitter input intermediate frequency signal, figure (b) shows the transmission frequency converter output and power amplifier output signal, and figure (b) shows the transmitter input intermediate frequency signal. Figure (c) is the first receiving frequency converter input signal, Figure (d) is
is the first received intermediate frequency signal, (e) is the second received frequency converter input signal, (f) is the second received - opening wave signal, and Fig. 3 is the waveform distortion due to selective fading. Receiving antenna input (, No. 1 is shown. 2: Transmitting frequency converter 3: Transmitting local oscillator 5:
? i? Band-stop filter 6: Transmission antenna 7: Reception antenna 10, 11: Bandpass filter 12.13: Reception frequency converter 14: Reception local oscillator 15: Distributor 16: Phase synthesizer

Claims (1)

[Claims] In a heterodyne radio device, an input intermediate frequency signal is frequency-converted above or below the local oscillation frequency by a transmission frequency converter on the transmission side, and this signal is amplified as it is and sent out from the transmission antenna as a transmission signal. After a transmission signal is received by one reception antenna, a high-frequency signal and a low-frequency signal are selected by a filter, respectively, as first and second reception signals, and then the first and second reception frequencies are respectively selected. A phase synthesis method characterized in that a converter performs frequency conversion on first and second intermediate frequency signals, and then phase synthesis is performed on the first and second intermediate frequency signals using a phase synthesizer.