JP2008205564A - Radio relay method, radio equipment and radio relay system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a radio relay method, a radio apparatus and a radio relay system which can perform radio communication by suppressing the influence of interference waves using a low-cost constitution, without the transmission speed deteriorating. <P>SOLUTION: An RF signal containing a signal of a first frequency f1 and/or a second frequency f2 is received, the received RF signal is mixed with one or more signals of a local oscillation frequency fLO, the signal of the frequency f1 or f2 is converted into a signal of an intermediate frequency fIF, the signal of the frequency fIF is mixed with one of more signals of the frequency fLO, and the mixed signal is converted into a signal of the frequency f1 or f2, which is different from the frequency before conversion to the fIF and has a relation of the formula 1 to transmits the converted signal, where fLOk is the k-th local oscillation frequency (k =1, 2, 3, ..., n) and n is a natural number. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  More particularly, the present invention relates to a wireless relay method, a wireless device, and a wireless system that suppress the influence of interference waves.

  Since microwave communication and millimeter wave communication tend to be introduced into high-speed transmission rate systems because they use a high frequency range, (1) narrow range communication with a wide occupied frequency band, (2) straightness of radio waves Has two characteristics such as line-of-sight communication. Therefore, it is difficult to construct a system that satisfies a sufficient radio wave environment over a wide range. These problems can be solved by using a repeater that relays communication between wireless devices. However, a repeater that is not economical is an obstacle to the widespread use of millimeter-wave band wireless systems.

  Depending on the frequency of a carrier wave (hereinafter also referred to as a carrier) used for communication between repeaters, reception performance deterioration due to jamming waves and a device configuration for suppressing the deterioration greatly differ. As an example, a system configuration in which the carrier frequency between repeaters and the carrier frequency between repeaters and radios (slave stations) are the same has excellent characteristics for effective use of the frequency, and the device configuration is relatively inexpensive. Although it is possible, since the same carrier frequency is used in the communication path between repeaters and the communication path between other radios, communication errors due to interference waves cannot be ignored.

  On the other hand, in the method in which the influence of the above-mentioned interference wave is eliminated and a different frequency is selected as the carrier frequency between the repeaters, since the frequency to be selected is changed between the repeaters, the repeater needs to receive which channel. Since there is a need for a carrier sense function or MAC control of a plurality of channels, the transmission rate is deteriorated. Further, when MAC control is performed, since the regenerative relay system is used instead of the non-regenerative relay system, a digital signal processing unit is necessary, and the signal processing unit for millimeter wave band ultra-high-speed transmission consumes a large amount of power and is expensive. . Therefore, the configuration of the relay system cannot be easily realized.

Also, in an environment where only the same transmitter (radio device) multipath fading is used, if repeater relay is not performed in the analog frequency band without OFDM demodulation (Orthogonal Frequency Division Multiplexing) in each repeater, It is necessary to consider a card interval of several minutes, and the effective transmission rate may be degraded.
In addition, assuming an OFDM demodulated regenerative repeater, an analog / digital converter and a signal processing unit are required, and it is difficult to realize an apparatus configuration at low cost, particularly in a high transmission rate system. Furthermore, transmission rate degradation also occurs due to OFDM demodulated signal processing time.

  As the regenerative repeater for OFDM demodulation as described above, for example, an OFDM transmission relay device that receives and amplifies an OFDM transmission signal output from the upper station and then outputs a transmission signal of the same frequency to the lower station. A delay time adjusting means for adjusting a delay time between transmission and reception caused by the transmission signal going to the receiving antenna, and a phase shift adjustment for the delay adjusted signal, An OFDM transmission relay apparatus comprising a phase shift adjustment means for canceling out a generated wraparound wave and a wraparound wave generated in the station is disclosed (for example, a patent) Reference 1).

JP 2000-49746 A (Claim 1)

However, the regenerative relay system has problems such as transmission rate degradation, increased power consumption, and high device cost. In the non-regenerative relay system, when the system is constructed with the same carrier, there is an influence of interference waves, which is different. When the system construction is realized by the carrier, there is a problem that the transmission speed is deteriorated due to the carrier sense time.
Accordingly, there has been a demand for a wireless relay method, a wireless device, and a wireless relay system that can perform wireless communication while suppressing the influence of an interference wave with an inexpensive configuration without deterioration in transmission speed.

但し、ｆ１：第１の周波数、ｆ２：第２の周波数、ｆＬＯｋ：第ｋ局部発振周波数（ｋ＝１，２，３，・・・ｎ ｎ：自然数）。 The radio relay method according to the present invention receives an RF signal including at least a signal of the first frequency (f1) and / or the second frequency (f2), and receives the received RF signal and one or more local oscillation frequencies ( fLO) signal is mixed to convert the first frequency (f1) or the second frequency (f2) signal into an intermediate frequency (fIF) signal, and the intermediate frequency (fIF) signal Different from the frequency before conversion to the intermediate frequency (fIF) by mixing the signal of the one or more local oscillation frequencies (fLO), the first frequency (f1) or the second It is converted into a signal of frequency (f2) and transmitted.

Where f1: first frequency, f2: second frequency, fLOk: k-th local oscillation frequency (k = 1, 2, 3,... N n: natural number).

但し、ｆ１：第１の周波数、ｆ２：第２の周波数、ｆＬＯｋ：第ｋ局部発振周波数（ｋ＝１，２，３，・・・ｎ ｎ：自然数）。 The wireless device according to the present invention includes one or a plurality of local oscillators that generate a signal having a predetermined local oscillation frequency (fLO), and at least the first frequency (f1) and / or the second frequency (f2). A first antenna that receives an RF signal including a signal, and the received RF signal and a signal of one or more local oscillation frequencies (fLO) are mixed to obtain the first frequency (f1) or the second First mixing means for converting a signal of frequency (f2) into a signal of intermediate frequency (fIF), and mixing the signal of intermediate frequency (fIF) and the signal of one or more local oscillation frequencies (fLO) Different from the frequency before conversion into the intermediate frequency (fIF), the second mixing means for converting into the RF signal of the first frequency (f1) or the second frequency (f2) having the relationship of the following formula: , Second to transmit the RF signal It is that an antenna.

Where f1: first frequency, f2: second frequency, fLOk: k-th local oscillation frequency (k = 1, 2, 3,... N n: natural number).

  A radio relay system according to the present invention includes one or a plurality of the radio devices.

  The present invention mixes a received RF signal with a signal of one or more local oscillation frequencies (fLO), and converts the signal of the first frequency (f1) or the second frequency (f2) to an intermediate frequency (fIF ), The intermediate frequency (fIF) signal and one or more local oscillation frequency (fLO) signals are mixed, and the intermediate frequency (fIF) is different from the frequency before conversion. By converting the signal to (f1) or the second frequency (f2) and transmitting the signal, the transmission speed is not deteriorated, and wireless communication that suppresses the influence of the interference wave can be performed with an inexpensive configuration.

の関係を有する搬送波周波数を使用する。 Embodiment 1 FIG.
FIG. 1 is a configuration diagram of a wireless relay system according to the first embodiment. The radio relay system according to the present embodiment is configured by one or a plurality of radio apparatuses 1 arranged as a repeater, and one or a plurality of transmission / reception stations 2 that transmit or receive an RF signal via the radio apparatus 1. The In this embodiment, while using a different carrier frequency (hereinafter also referred to as a carrier) between adjacent wireless devices 1 (repeaters), an inexpensive system configuration that does not require MAC control and multi-channel carrier sense is realized. The RF signal is relayed by a non-regenerative relay system that has been made possible.
If the first frequency (f1) and the second frequency (f2) used as the carrier frequency by the wireless device 1 are the local oscillation frequency fLO (described later) of the wireless device 1,

A carrier frequency having the following relationship is used.

Here, when the frequency obtained by multiplying (mixing) the received RF signal and the local oscillation frequency fLO and performing frequency conversion (down-conversion) by the operation described later is an intermediate frequency fIF, The carrier frequencies of the frequency (f1) and the second frequency (f2) have the following relationship.
Carrier frequency = fLO ± fIF (2)

  In the present embodiment, carrier frequency = fLO + fIF is used as the first frequency (hereinafter simply referred to as f1), and carrier frequency = fLO−fIF is used as the second frequency (hereinafter simply referred to as f2). An RF signal is transmitted / received by switching between f1 and f2 such that the carrier frequency used is alternately between one or a plurality of wireless devices 1 or between the wireless device 1 and the transmitting / receiving station 2.

  FIG. 2 is a block diagram showing a configuration of the radio apparatus according to the first embodiment. As shown in FIG. 2, radio apparatus 1 according to the first embodiment includes a receiving unit and a transmitting unit, and the receiving unit includes antenna 99, RF band-pass filter 100, low noise amplifying unit 101, and the like. , IQ mixer section 102, switch section 103, 90 ° HYB (phase shift coupler) 104, IF band BPF section 105, quadrature demodulator 106, baseband low pass filter 107, amplifier 108, Consists of. The I-Q mixer unit 102 and the 90 ° HYB 104 constitute an image rejection mixer 110. The antenna 99 corresponds to the first antenna in the present invention, the switch unit 103 corresponds to the first switch unit in the present invention, and the switch unit 103 and the image rejection mixer 110 make up the first antenna in the present invention. 1 mixing means.

The transmission unit includes a variable gain amplifier 111, a baseband low-pass filter 112, an IQ mixer unit 113, a switch unit 114, a 90 ° HYB 115, an IQ mixer unit 116, an amplifier 117, An RF band bandpass filter 118 and an antenna 120 are included. The 90 ° HYB 115 and the IQ mixer unit 116 constitute a phase shift type SSB modulator 119. The antenna 120 corresponds to the second antenna of the present invention, and the switch unit 114 corresponds to the second switch unit of the present invention. The switch unit 114 and the phase shift type SSB modulator 119 constitute the present invention. Constitutes a second mixing means.
Further, by the operation described later, the RSSI detection unit / SW control unit 109 that inputs a switch control signal to the switch unit 103 and the switch unit 114, and the local oscillation frequency fLO are transmitted to the IQ mixer unit 102 and the IQ mixer unit 116. A first local oscillator 201 for inputting a signal and a second local oscillator 202 for inputting a signal having a local oscillation frequency fLO to the quadrature demodulator 106 and the IQ mixer unit 113 are provided. In the present embodiment, as shown in FIG. 2, two sets of receiving units and transmitting units are provided, and signals of different carrier frequencies are received and transmitted by the operation described later. That is, the switch control signal so that one of the two sets (for example, the upper side of FIG. 2) receives f1 and transmits f2, and the other (for example, the lower side of FIG. 2) receives f2 and transmits f1. (Hereinafter, a combination of frequencies is referred to as frequency arrangement). The operation of the wireless device 1 having such a configuration will be described next by dividing it into (1) a receiver and (2) a transmitter.

(1) Receiving Unit First, the operation of the receiving unit will be described with reference to FIGS. 3A to 3E as appropriate based on FIG.
FIG. 3 is a diagram for explaining the operation of down-conversion according to the first embodiment. 3A is a diagram illustrating a relationship between f1, f2 and fLO of the RF input signal, and FIG. 3B is a diagram illustrating an I-phase IF output signal output from the I-Q mixer unit 102. FIG. 3C shows a Q-phase IF output signal output from the I-Q mixer unit 102, and FIG. 3D shows that the I-phase and Q-phase IF output signals are input to the 90 ° HYB 104. FIG. 3E is a diagram showing a first pattern, and FIG. 3E is a diagram showing a second pattern inputted to the 90 ° HYB 104 of the I-phase and Q-phase IF output signals.

  The RF signal received by the antenna 99 is amplified by the low noise amplification unit (LNA) 101 through the RF band-pass filter 100 and input to the IQ mixer unit (down converter) 102. In addition, a signal of a local oscillation frequency (fLO) (hereinafter referred to as a 1st-LO signal) input from the first local oscillator 201 is input to the IQ mixer unit 102. At this time, an in-phase 1st-LO signal is input to the I-phase side of the I-Q mixer unit 102, and a 1st-LO signal shifted by + π / 2 phase is input to the Q-phase side.

The I-Q mixer unit 102 mixes (multiplies) the input RF signal and the 1st-LO signal, and down-converts the signal to an intermediate frequency (fIF) signal (hereinafter referred to as IF).
At this time, as shown in FIG. 3A, when an RF signal including f1 and f2 having the relationship of the above-mentioned equation (2) “fLO ± fIF” is input (here, f1 is the upper sideband: USB). , F2 is a lower sideband: LSB), the IF output of the I-Q mixer unit 102 is connected to the I-phase side and the Q-phase side as shown in FIG. 3B and FIG. As a result of multiplication of the two RF signals of 1 and f2 and the 1st-LO signal, two identical frequencies having intermediate frequencies f1-fLO and fLO-f1 are down-converted. Each of the down-converted intermediate frequency (fIF) signals has the same frequency but a different phase. That is, both the I-phase IF output signals corresponding to f1 and f2 have a phase of 0 °, and the Q-phase IF output signal has a phase difference of + π / 2 for the USB signal and −π / 2 for the LSB signal.

  When the fIF signals on the I-phase and Q-phase sides having different phases are controlled by the switch unit 103 by an operation to be described later and input to the 90 ° HYB 104, they are shown in FIGS. 3 (d) and 3 (e). As shown in the 90 ° HYB input setting diagram shown in FIG. 3, in the pattern 1 (FIG. 3D) and the pattern 2 (FIG. 3E), the IQ signal connected to the input port of the 90 ° HYB 104 is inverted. The switch unit 103 is responsible for switching the connection. The switch unit 103 is controlled to be switched by a switch control signal input from the RSSI detection unit / SW control unit 109, which will be described in detail later.

In the pattern 1 (LSB sideband selection case) shown in FIG. 3D, the input to the 90 ° HYB 104 passes through the 90 ° HYB 104 and is then output from the I-Q mixer unit 102. The USB side is delayed by π / 2 (−90 °) to become a phase difference of zero, and is coupled with the USB side (phase difference of zero) of the I-phase IF output signal by 3 dB and output. On the other hand, the LSB side of the Q-phase IF output signal is delayed by π / 2 (−90 °) to a phase difference of π, which is canceled with the LSB side (zero phase difference) of the I-phase IF output signal. At the output end of 90 ° HYB 104, only the IF signal on the USB side is extracted.
On the other hand, in the pattern 2 (USB sideband selection case) shown in FIG. 3E, the input to the 90 ° HYB 104 passes through the 90 ° HYB 104, and then the I-phase IF output from the IQ mixer unit 102. The LSB side of the output signal is delayed by π / 2 (−90 °) to a phase of −π / 2, and 3 dB coupled to the LSB side (phase −π / 2) of the Q-phase IF output signal is output. On the other hand, the USB side of the I-phase IF output signal is phase-π / 2 delayed by π / 2 (-90 °), and canceled with the USB side (phase -π / 2) of the Q-phase IF output signal. Finally, only the LSB-side IF signal is extracted at the output end of the 90 ° HYB 104.

  The IF signal of the intermediate frequency (fIF) corresponding to the extracted f1 (USB side) or f2 (LSB side) is input to the quadrature demodulator 106 via the IF band BPF unit 105 which is a bandpass filter of the intermediate frequency band. The signal is multiplied by a second local oscillation frequency signal (hereinafter referred to as a 2nd-LO signal) input from the second local oscillator 202 and demodulated to a baseband signal band, and an amplifier 108 via a baseband lowpass filter 107. And then transmitted to the transmitter. At this time, the output signal of the amplifier 108 is transmitted in parallel to the RSSI detector / SW controller 109. Next, details of the configuration and operation of the RSSI detector / SW controller 109 will be described with reference to FIGS. 4 and 5. FIG.

  FIG. 4 is a block diagram illustrating a configuration of the RSSI detection / SW control unit according to the first embodiment. As shown in FIG. 4, the RSSI detection unit / SW control unit 109 includes an RSSI detection unit and an SW control unit. The RSSI detection unit includes an LPF 301 that is a low-pass filter and a low conversion speed analog-digital converter. An ADC 302, a comparator 303, a threshold value setting unit 304, and a voltage adjustment unit 305 are provided. Each unit includes two sets, each corresponding to two sets of a reception unit and a transmission unit. The SW control unit includes a switch switching control unit 300 and outputs a switch control signal to the switch units 103 and 114 by an operation described later.

  With such a configuration, the output signal of the amplifier 108 input to the RSSI detection unit is input to the ADC unit 302 via the LPF 301, and the ADC unit 302 performs analog-digital conversion on the input signal to perform RSSI (reception electric field). The comparator 303 compares the input RSSI signal with the threshold value stored in advance in the threshold value setting unit 304 and outputs the result to the switch switching control unit 300. Further, the comparator 303 outputs the RSSI signal to the voltage adjustment unit 305, and the voltage adjustment unit 305 adjusts the output signal of the amplifier 108 and outputs it as a gain control signal (described later) of the variable gain amplifier 111.

FIG. 5 is an operation flowchart of the RSSI detection / SW control unit according to the first embodiment.
(S101) First, in the switch switching control unit 300, as a default, a switch control signal to the switch unit 103 that causes the 90 ° HYB 104 to output the IF signal on the USB side (f1) of the RF signal is set (priority). Channel f1). The priority channel is not limited to this, and may be f2.
(S102) Based on the input switch control signal, the switch unit 103 switches to the connection to be the connection of the above-described pattern 1, and causes the 90 ° HYB 104 to extract (receive) the IF signal of f1 by the above-described operation. The received IF signal of f1 is demodulated to the basin band signal band by the above-described operation, and then input to the amplified RSSI detection unit to obtain the RSSI signal.
(S103) The comparator 303 compares the RSSI signal with a threshold value stored in advance in the threshold value setting unit 304, and outputs the result to the switch switching control unit 300.
(S104) When the RSSI value is smaller than the threshold, the switch switching control unit 300 outputs a switch control signal for switching the connection of the current switch unit 103. That is, when the connection of the switch unit 103 is the pattern 1 described above, the pattern is switched to the pattern 2 (f1 to f2), and when the connection is the pattern 2, the pattern is switched to the pattern 1 (f2 to f1).
(S105) On the other hand, when the RSSI value is larger than the threshold value, the comparator 303 sets the acquired RSSI value in the threshold value setting unit 304 as a new threshold value.
(S106) Next, the switch switching control unit 300 outputs a switch control signal for switching the current connection of the switch unit 103. That is, when the connection of the switch unit 103 is the pattern 1 described above, the pattern is switched to the pattern 2 (f1 to f2), and when the connection is the pattern 2, the pattern is switched to the pattern 1 (f2 to f1).
(S107) The switch unit 103 switches the connection based on the switch control signal input from the switch switching control unit 300, receives the IF signal of f1 or f2 by the same operation as described above, and responds by the RSSI detection unit. The RSSI signal to be acquired is acquired.
(S108) Next, the comparator 303 compares the new threshold value set in the above (S105) with the acquired RSSI signal, and outputs the result to the switch switching control unit 300.
(S109) When the RSSI value is larger than the threshold value, the switch switching control unit 300 holds the switch control signal currently output to the switch unit 103.
(S110) On the other hand, when the RSSI value is smaller than the threshold, the switch switching control unit 300 outputs and holds a switch control signal for switching the connection of the current switch unit 103. That is, the switch control signal for returning to the connection state before the connection is switched in (S106) is output and held.
(S111) The RSSI detection unit / SW control unit 109 repeats the operations of (S101) to (s110) after a predetermined time has elapsed.

  By such an operation, in the reception unit, a signal having a high reception electric field strength (RSSI) of the first frequency (f1) or the second frequency (f2) is converted to a signal (IFIF) of the intermediate frequency (fIF). ) And demodulated to a basin band signal band.

(2) Transmitter The operation of the transmitter will be described again with reference to FIG. In FIG. 2, the output signal of the amplifier 108 transmitted from the receiving unit is input to the variable gain amplifier 111. The variable gain amplifier 111 amplifies the signal based on the gain control signal from the voltage adjusting unit 305 described above, and performs baseband low pass. The signal is input to the IQ mixer unit 113 via the filter 112. The I-Q mixer unit 113 multiplies the second local oscillation frequency signal (2nd-LO signal) input from the second local oscillator 202 and performs quadrature modulation on the intermediate frequency signal (IF). The quadrature-modulated I-phase and Q-phase intermediate frequency signals (IF) are switched to the 90 ° HYB 115 by the switch unit 114 by an operation described later. The 90 ° HYB 115 divides the input intermediate frequency signal (IF) into two parts, phase-shifts one of them by π / 2, and outputs the resulting signal to the IQ mixer unit 116. The I-Q mixer unit 116 multiplies the input intermediate frequency signal (IF) and the 1st-LO signal, respectively, up-converts the signals into f1 and f2 RF signals, and converts either the f1 or f2 signal. Cancel and output the other. The RF signal output from the I-Q mixer unit 116 is amplified by the amplifier 117 and transmitted by the antenna 120 via the RF band-pass filter 118.

  When the switch switching control unit 300 of the RSSI detection unit / SW control unit 109 described above outputs a switch control signal to the switch unit 103 of the reception unit, it also outputs a switch control signal to the switch unit 114 of the transmission unit. The switch control signal is output as a control signal for switching the switch unit 114 so as to up-convert to a carrier frequency different from the frequency down-converted to the intermediate frequency signal (IF) by the receiving unit. The details of the up-conversion operation of the IQ mixer unit 116 that outputs either f1 or f2 by switching the connection of the switch unit 114 will be described with reference to FIG.

FIG. 6 is an explanatory diagram of the operation of up-conversion according to the first embodiment.
The phase of the spectrum waveform when the IF signal passes through 90 ° HYB115 is output with the phase of either the I-phase or Q-phase output advanced by π / 2 (+ 90 °) by the switch switching control of the switch unit 114. The In pattern 1 (LSB sideband selection case) shown in FIG. 6A, the 90-degree HYB115 Q-phase output is π / 2-phased, and the I-phase output is output in-phase. The 90 ° HYB 115 output signal is multiplied by the 1st-LO signal by the I-Q mixer unit 116 and up-converted to an RF band signal corresponding to each of the I and Q phases. As shown in FIG. 6, the upper sideband of the LO signal is RF _USB and the lower sideband is RF _LSB with respect to the frequency (fLO) of the 1st-LO signal. These double sideband signals correspond to f1 and f2. Here, f1 is the USB side and f2 is the LSB side.
At this time, as shown in FIG. 6A, among the RF signals corresponding to the Q-phase signal, RF _USB has a phase difference π and RF _LSB has the same phase. Further, both RF signals corresponding to the I-phase signal are in phase. Therefore, the Q-phase and I-phase RF _USBs cancel each other with a phase difference of π, and RF _LSB , that is, the RF signal of f2 is output from the IQ mixer unit 116.

On the other hand, in the pattern 2 (USB sideband selection case) shown in FIG. 6B, the 90 ° HYB 115 I-phase output is phase-shifted by π / 2, and the Q-phase output is output in the same phase. The 90 ° HYB 115 output signal is multiplied by the 1st-LO signal by the I-Q mixer unit 116 and up-converted to an RF band signal corresponding to each of the I and Q phases.
At this time, as shown in FIG. 6B, among the RF signals corresponding to the Q-phase signal, RF _LSB has a phase difference π, and RF _USB has the same phase. Further, both RF signals corresponding to the I-phase signal are in phase. For this reason, the RF _LSBs of the Q phase and the I phase cancel each other with a phase difference of π, and RF _USB , that is, the RF signal of f1 is output from the IQ mixer unit.

  As described above, in the first embodiment, the carrier frequency to be received is switched without switching the 1st-LO signal, and the RF signal having a carrier frequency different from the received carrier frequency is switched, so that the configuration is simple and inexpensive. In addition, it is possible to select a frequency different from the frequency used by the other wireless device 1 or the transmission / reception station 2 adjacent to the wireless device 1 and suppress the influence of the interference wave, thereby enabling stable wireless communication.

Embodiment 2. FIG.
In the first embodiment, the receiving unit demodulates the intermediate frequency signal (IF) into a baseband signal, and the transmitting unit modulates the baseband signal into the intermediate frequency signal (IF). In the second mode, the signal is transmitted to the transmission unit in the intermediate frequency band without being demodulated to the baseband by the reception unit.

  FIG. 7 is a block diagram showing a configuration of a radio apparatus according to the second embodiment. As shown in FIG. 7, in the second embodiment, from the configuration of the first embodiment, the quadrature demodulator 106, the baseband low-pass filter 107, the amplifier 108, the baseband low-pass filter 112, and I The Q mixer unit 113 and the second local oscillator 202 (hereinafter referred to as baseband signal components) are omitted. Other configurations and operations are the same as those in the first embodiment.

  In the first embodiment, the reception band limiting filter characteristic is obtained by the baseband low pass filter 107, but in the second embodiment, the IF band BPF unit 105 uses the baseband low pass filter. By obtaining a reception band limiting filter characteristic equivalent to 107, the same advantage as in the first embodiment can be obtained.

  As described above, in the second embodiment, in addition to the effects of the first embodiment, the components of the baseband signal can be deleted, and this can reduce the degree of integration. An inexpensive and small wireless device can be configured.

Embodiment 3 FIG.
The frequency arrangement of f1 and f2 of the radio apparatus 1 shown in the first and second embodiments can be applied to the half-duplex system by the radio system, but can be applied to the full-duplex system. Can not. In the third embodiment, the frequency arrangement is applicable to the full duplex multiplexing method. The configuration and operation of the wireless device 1 in the present embodiment are the same as those in the first or second embodiment.

  FIG. 8 is a configuration diagram of a wireless relay system according to the third embodiment. As shown in FIG. 8, each wireless device 1 receives the same carrier frequency by two sets of reception units and transmission units, and transmits a frequency different from the received carrier frequency. That is, the switch switching control unit 300 outputs switch control signals having the same connection pattern to the switch units 103 of the two sets of receiving units, and the same connection to the switch units 114 of the two sets of transmission units. A switch control signal that is a pattern is output.

  As described above, in the third embodiment, in addition to the effects of the first and second embodiments, the switch switching control unit 300 includes the switch unit 103 and the switch so that the frequency arrangement can be applied to the full duplex multiplexing method. By switching the unit 114, wireless communication by the full-duplex multiplexing method becomes possible.

Embodiment 4 FIG.
In the fourth embodiment, f1 and f2 having the relationship of the following expression (3) are used as the relationship between the frequencies f1 and f2 used by the wireless apparatus 1 as a carrier wave. Here, assuming that the carrier frequency used is fLO _1st for the first local oscillation frequency, fLO _2nd for the second local oscillation frequency, and fIF _2nd for the second intermediate frequency,

Carrier frequency = fLO _1st + fLO _2nd ± fIF _2nd (a carrier frequency having the relationship of the expression (3)) is used.

That is, f1 and f2 have the relationship of the following expression (4), where the k-th local oscillation frequency is fLOk.

In the present embodiment, the case where there are two local oscillation frequencies will be described. However, the present invention is not limited to this, and any number of local oscillation frequencies may be used, and the k-th local oscillation frequency is set to fLOk (k = 1, 2, 3,..., N n: natural number), the following equation (5) is satisfied.

  The configuration and operation of radio apparatus 1 of the fourth embodiment that uses such a carrier frequency will be described below.

FIG. 9 is a block diagram showing a configuration of a radio apparatus according to Embodiment 4. In FIG. In FIG. 9, the same components as those in the first embodiment described above are denoted by the same reference numerals and description thereof is omitted. Further, in order to show the difference from the configuration of the first embodiment (FIG. 2), the right half is omitted. As shown in FIG. 9, in the present embodiment, an RF band bandpass filter 100, a down converter (mixer) 401, between the low noise amplification unit 101 and the IQ mixer unit 102 of the reception unit, An IF band-pass filter 402, and an RF band-pass filter 118, an up-converter (mixer) 403, an IF-band band-pass filter 404, between the IQ mixer unit 116 and the amplifier 117 of the transmission unit Is provided. Furthermore, a first local oscillator 201 for inputting a signal of the first local oscillation frequency (fLO _1st ) (hereinafter referred to as a 1st-LO signal) to the down converter (mixer) 401 and the up converter (mixer) 403, and an IQ mixer A second local oscillator 202 for inputting a second local oscillation frequency (fLO _2nd ) signal (hereinafter referred to as a 2nd-LO signal) to the unit 102 and the IQ mixer unit 116; an orthogonal demodulator 106; and an IQ mixer unit 113 includes a third local oscillator 203 that inputs a signal of the third local oscillation frequency (fLO _3rd ) (hereinafter referred to as a 3rd-LO signal). Next, the operation of the present embodiment having such a configuration will be described.

The RF signal received by the antenna 99 at the receiving unit is amplified by the low noise amplifying unit (LNA) 101 via the RF band-pass filter 100 by the same operation as in the first embodiment described above. This RF signal is input to the down converter 401 via the RF band-pass filter 100. The down converter 401 multiplies the input RF signal by the 1st-LO signal and down-converts the signal to a first intermediate frequency (fIF _1st ) signal (hereinafter referred to as IF _1st signal). This IF _1st signal is input to the I-Q mixer unit 102 via the IF band-pass filter 402, and the I-Q mixer unit 102 multiplies the input IF _1st signal by the 2nd-LO signal, Each of the I-phase and Q-phase is down-converted into a second intermediate frequency (fIF _2nd ) signal (hereinafter referred to as IF _2nd signal). This IF _2nd signal is received (extracted) by either switching of the switching unit 103 to receive (extract) the IF _2nd signal of either f1 or f2, and is orthogonally demodulated via the IF band BPF unit 105, as in the first embodiment. The signal is input to the device 106, multiplied by the 3rd-LO signal, and demodulated into a basin band signal band.

On the other hand, in the transmission unit, a baseband signal is input to the IQ mixer unit 113, and the IQ mixer unit 113 multiplies the 3rd-LO signal to perform quadrature modulation on the IF _2nd signal. The quadrature-modulated I-phase and Q-phase IF _2nd signals are input to the IQ mixer unit 116 via the switch unit 114 and 90 ° HYB 115 by the same operation as in the first embodiment. The I-Q mixer unit 116 multiplies the input IF _2nd signal and the 2nd-LO signal, up-converts the IF _1st signal corresponding to either f1 or f2, and passes through the IF band-pass filter 404. To the up-converter 403. The up-converter 403 multiplies the input IF _1st signal by the 1st-LO signal to up-convert it into an RF signal of f1 or f2, and inputs it to the amplifier 117 via the RF band-pass filter 118. This RF signal is amplified by the amplifier 117 and transmitted by the antenna 120 via the RF band-pass filter 118.

  As described above, in this embodiment, a conversion operation from the RF band to the IF band (reception unit) and the IF band to the RF band (transmission unit) is added, and the frequency of the IF band is used to support either f1 or f2. The intermediate frequency signal is generated and extracted.

  As described above, in the fourth embodiment, the frequency band for generating and extracting the carrier wave of f1 or f2 is shifted to the IF band of the frequency band lower than the RF band, so that the amplitude error and phase error of the IQ mixer can be improved. Characteristics are obtained.

  In addition, when high-speed AD conversion and high-speed digital signal processing become possible due to recent or future development of semiconductor microfabrication technology, by dropping to a lower frequency band as in the fourth embodiment, π / Digitization of 90 ° HYB that performs phase advance and delay of 90 ° phase of 2 phases, or digitization of 90 ° phase advance and delay phase of fLO input to IQ mixer, digitization of IQ mixer section Thus, it is possible to improve the characteristics and stabilize the characteristics by digitization.

Embodiment 5. FIG.
FIG. 10 is a configuration diagram of a radio relay system according to the fifth embodiment. In the fifth embodiment, as shown in FIG. 10, the antennas have the same polarization plane between adjacent radio apparatuses 1 or transmission / reception stations 2, and the polarization planes of the reception side and transmission side antennas of each radio apparatus 1 Install the antennas so that they are different. For example, in FIG. 8, the transmission and reception antennas for communication between the transmission / reception station 2-1 and the radio apparatus 1-1 are attached so that the polarization planes are vertical polarization planes, and the radio apparatus 1-1 and the radio apparatus 1-2. Are attached so that the polarization planes of the transmission and reception antennas that communicate with each other become horizontal polarization planes, and the polarization planes of the transmission and reception antennas that communicate between the radio apparatus 1-2 and the transmission / reception station 2 become vertical polarization planes. Attach to.

  As described above, in the fifth embodiment, the reception side and the transmission side antennas are installed so that their polarization planes are different from each other, thereby suppressing the deterioration of the reception characteristics due to the interference wave of the carrier frequency, and a stable communication path. Can be provided.

  In addition, the antenna 99 and the antenna 120 of the wireless device 1 according to the first to fourth embodiments are attached so that the polarization planes are different from each other as described above, thereby further suppressing degradation of reception characteristics due to interference waves. Is possible.

  In the first to fifth embodiments, an example in which the wireless device 1 is applied to a repeater of a wireless relay system has been described. It is also applicable to. An RF signal transmitted from the own radio apparatus 1 is transmitted as a radar transmission wave, and a carrier sense is performed with an RSSI detection function for a frequency that was originally scheduled to be used by the receiving unit immediately before the transmission of the radar transmission wave. Thus, using the carrier wave f1 or f2 that can be used without switching the LO frequency, it is possible to select a frequency at which the reflected wave of the radar transmission wave transmitted by the radio apparatus 1 can be received satisfactorily.

1 is a configuration diagram of a radio relay system according to Embodiment 1. FIG. 1 is a block diagram showing a configuration of a radio apparatus according to Embodiment 1. FIG. FIG. 6 is an operation explanatory diagram of down-conversion according to the first embodiment. 3 is a block diagram showing a configuration of an RSSI detection / SW control unit according to Embodiment 1. FIG. 3 is an operation flowchart of an RSSI detection / SW control unit according to the first embodiment. 6 is an operation explanatory diagram of up-conversion according to Embodiment 1. FIG. 6 is a block diagram showing a configuration of a radio apparatus according to Embodiment 2. FIG. FIG. 6 is a configuration diagram of a wireless relay system according to a third embodiment. FIG. 10 is a block diagram illustrating a configuration of a wireless device according to a fourth embodiment. FIG. 10 is a configuration diagram of a wireless relay system according to a fifth embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Radio | wireless apparatus, 2 Transmission / reception station, 99 Antenna, 100 RF band band pass filter, 101 Low noise amplification part, 102 IQ mixer part, 103 Switch part, 104 90 degree HYB, 105 IF band BPF part, 106 Quadrature demodulator 107 baseband low pass filter, 108 amplifier, 109 RSSI detection unit / SW control unit, 110 image rejection mixer, 111 variable gain amplifier, 112 baseband low pass filter, 113 IQ mixer unit, 114 switch unit, 115 90 ° HYB, 116 IQ mixer section, 117 amplifier, 118 RF band bandpass filter, 119 phase shift SSB modulator, 120 antenna, 201 first local oscillator, 202 second local oscillator, 203 third local oscillator, 300 Switch off Control unit, 301 Low-pass filter, 302 ADC unit, 303 Comparator, 304 Threshold setting unit, 305 Voltage adjustment unit, 401 Down converter, 402 IF band-pass filter, 403 Up converter, 404 IF band-pass filter, f1 Carrier frequency , F2 Carrier frequency, fIF intermediate frequency, fLO Local oscillation frequency.

Claims (11)

Receiving an RF signal comprising a signal of at least a first frequency (f1) or / and a second frequency (f2);
The received RF signal is mixed with one or more local oscillation frequency (fLO) signals, and the first frequency (f1) or the second frequency (f2) signal is an intermediate frequency (fIF) signal. Converted to
The intermediate frequency (fIF) signal and the one or a plurality of local oscillation frequencies (fLO) signals are mixed, and the intermediate frequency (fIF) is different from the frequency before conversion, and has a relationship of the following formula: A radio relay method characterized in that the signal is converted into a signal having the frequency (f1) or the second frequency (f2) and transmitted.

Where f1: first frequency, f2: second frequency, fLOk: k-th local oscillation frequency (k = 1, 2, 3,... N n: natural number). One or more local oscillators that generate signals of a predetermined local oscillation frequency (fLO);
A first antenna that receives an RF signal including a signal of at least a first frequency (f1) or / and a second frequency (f2);
The received RF signal is mixed with one or more local oscillation frequency (fLO) signals, and the first frequency (f1) or the second frequency (f2) signal is changed to an intermediate frequency (fIF). First mixing means for converting to a signal;
The intermediate frequency (fIF) signal and the one or more local oscillation frequency (fLO) signals are mixed, and the intermediate frequency (fIF) is different from the frequency before conversion, and has a relationship of the following equation: Second mixing means for converting to an RF signal having a frequency (f1) or a second frequency (f2) of
And a second antenna for transmitting the RF signal.

Where f1: first frequency, f2: second frequency, fLOk: k-th local oscillation frequency (k = 1, 2, 3,... N n: natural number). RSSI detection / SW control for detecting the received electric field intensity of the received signal of the first frequency (f1) and / or the second frequency (f2) and outputting a switch control signal corresponding to the received electric field intensity Part
Based on the switch control signal, the first mixing means outputs a signal having a frequency with a high received electric field strength, of the first frequency (f1) or the second frequency (f2), to an intermediate frequency (fIF The radio apparatus according to claim 2, wherein the radio apparatus converts the signal into a signal.   The second mixing means, based on the switch control signal, of the first frequency (f1) or the second frequency (f2), a frequency different from the frequency before the conversion to the intermediate frequency (fIF) The radio apparatus according to claim 3, wherein the radio apparatus converts the signal into a radio signal. Each of the first antenna, the first mixing unit, the second mixing unit, and the second antenna (hereinafter collectively referred to as a relay unit) includes two sets,
One of the relay means is
Of the received RF signal, the first frequency (f1) signal is converted into an intermediate frequency (fIF) signal, and the intermediate frequency (fIF) signal is converted into the second frequency (f2) signal. Then send
The other of the relay means is
Of the received RF signal, the second frequency (f2) signal is converted into an intermediate frequency (fIF) signal, and the intermediate frequency (fIF) signal is converted into the first frequency (f1) signal. The wireless device according to claim 2, wherein the wireless device transmits the data. The first mixing means includes
The RF signal and the local oscillation frequency (fLO) signal are mixed, and an intermediate frequency signal (I-phase IF) corresponding to each of the first frequency (f1) and the second frequency (f2). ) And a quadrature component intermediate frequency signal (Q phase IF), and either the in-phase component intermediate frequency signal (I phase IF) or the quadrature component intermediate frequency signal (Q phase IF) is π / 2 After delaying the phase, the intermediate frequency signal (I-phase IF) of the in-phase component and the intermediate frequency signal (Q-phase IF) of the quadrature component are combined to generate the first frequency (f1) or the second frequency. An image rejection mixer that cancels any of the intermediate frequency (fIF) signals corresponding to (f2) and outputs the other;
A first switch that switches between the in-phase component intermediate frequency signal (I-phase IF) or the quadrature component intermediate frequency signal (Q-phase IF) delayed by π / 2 by the image rejection mixer based on the switch control signal. The wireless device according to claim 2, further comprising: The second mixing means includes
The input intermediate frequency (fIF) signal is divided into two, and one of the divided intermediate frequency signals (IF) is phase-shifted by π / 2, and then the divided intermediate frequency signal (IF) and the Each of the signals of the local oscillation frequency (fLO) is mixed and converted into signals of the first frequency (f1) and the second frequency (f2) corresponding to the divided intermediate frequency signals (IF), respectively. A phase shift type SSB modulator that performs post-synthesis, cancels either the signal of the first frequency (f1) or the second frequency (f2), and outputs the other;
7. A second switch section that switches the divided intermediate frequency signal (IF) that is phase-shifted by π / 2 based on the switch control signal. A wireless device according to any one of the above. The RF signal and the signals of the plurality of kth local oscillation frequencies (fLOk) are mixed and converted to a second intermediate frequency, and the second intermediate frequency signal is changed to the RF signal to convert the first signal. Third mixing means for inputting to the mixing means;
The second intermediate frequency signal output from the second mixing means and the plurality of kth local oscillation frequencies (fLOk) are mixed to obtain the first frequency (f1) or the second frequency. The wireless device according to claim 2, further comprising: a fourth mixing unit that converts the signal into an RF signal having a frequency (f2).   The radio apparatus according to claim 2, wherein the first antenna and the second antenna are installed such that their polarization planes are different from each other.   A wireless relay system comprising one or a plurality of wireless devices according to claim 2. Comprising one or more transmitting and receiving stations for transmitting or / and receiving an RF signal including at least a signal of a first frequency (f1) and / or a second frequency (f2),
The wireless relay system according to claim 10, wherein the wireless device relays an RF signal transmitted or received by the transmitting station.

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