JP2011250093A - Receiver and transmitter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transceiver that have increased reception sensitivity, relaxed performance required for a switch for switching channels of transmitting/received signals, and a design simplified by using low frequencies.SOLUTION: The receiver includes plural antennas 1 for receiving plural radio frequency signals, plural low noise amplifiers 2 that amplify the radio frequency signals received by the antennas 1, plural signal distributors 3 that distribute output signals of the low noise amplifiers 2, plural band-pass filters 4 that eliminate unnecessary waves from output signals of the signal distributors 3, plural down converts 5 that each include a local oscillator 7 and a mixer 6 and that convert the received radio frequency signals into baseband signals, a switching matrix 8 that is connected to the down converts 5 and that switches plural input signals to plural output signals, plural low-pass filters 9 that are connected to the switching matrix 8 and that eliminate unnecessary waves, and plural analog-to-digital converts 10 that convert the baseband signals into digital signals.

Description

  The present invention relates to a receiver and a transmitter that transmit and receive high-frequency band signals such as UHF, microwaves, and millimeter waves, and more particularly to a receiver and a transmitter that constitute a multi-beam compatible satellite communication repeater. .

  A conventional receiver will be described with reference to FIG. FIG. 7 is a diagram illustrating a configuration of a conventional receiver (see, for example, Patent Document 1). In the following, in each figure, the same reference numerals indicate the same or corresponding parts.

  In FIG. 7, a conventional receiver includes an antenna 1 that receives a signal, a signal distributor 3 that distributes a signal input to the antenna 1, a switch 8A that switches a path of the received signal, and an unnecessary wave in a high frequency band. Are provided, a band-pass filter (BPF) 4 that removes noise, a demodulator 5A that converts and demodulates a high-frequency signal into a baseband signal, and a digital unit 11 that processes the baseband signal.

  As shown in FIG. 7, the conventional receiver is provided with a high-frequency band switch 8A in front of the demodulator 5A as signal switching means.

Japanese Patent No. 3828056

  In the conventional receiver as described above, the switch 8A for switching the path of the received signal is arranged in the previous stage of the demodulator 5A, that is, in the high frequency band, so that the signal due to the loss of the switch 8A as a whole receiver. There was a problem that the noise-to-noise ratio deteriorated.

  In addition, because of the high frequency band, there is a problem that it is difficult to reduce the loss and the isolation of the switch 8A.

  Further, in the transmitter, when the switch is arranged in the high frequency band, there is a problem that it is difficult to reduce the loss and the isolation of the switch as in the receiver. Also, the transmitter has the same problems as the receiver.

  The present invention has been made to solve the above-described problems, and in particular, has a plurality of antennas, and a multi-beam satellite-borne repeater that transmits and receives signals in a plurality of frequency bands using each antenna. Receiver and transmitter capable of improving the reception sensitivity of the receiver and relaxing the required performance for the switch for switching the path of the transmission / reception signal, and simplifying the design by lowering the frequency The purpose is to obtain.

  A receiver according to the present invention distributes a plurality of antennas that receive a plurality of high-frequency signals, a plurality of low-noise amplifiers that amplify the high-frequency signals received by the plurality of antennas, and output signals of the plurality of low-noise amplifiers A plurality of signal distributors, a plurality of band-pass filters for removing unnecessary waves from the output signals of the plurality of signal distributors, and a local oscillator and a mixer, each of which converts a received high-frequency signal into a baseband signal A plurality of down converters connected to the plurality of down converters, a signal switching means for switching a plurality of input signals to a plurality of output signals, and connected to the signal switching means for removing unnecessary waves in the baseband signal band. A plurality of low-pass filters and a plurality of A / Bs for converting baseband signals from the plurality of low-pass filters into digital signals It is intended and a converter.

  According to the receiver according to the present invention, it is possible to improve the reception sensitivity, relax the required performance for the switch that switches the path of the received signal, and simplify the design by reducing the frequency.

It is a figure which shows the structure of the receiver which concerns on Embodiment 1 of this invention. It is a figure which shows the structure of the receiver which concerns on Embodiment 2 of this invention. It is a figure which shows the structure of the receiver which concerns on Embodiment 3 of this invention. It is a figure which shows the structure of the transmitting apparatus which concerns on Embodiment 4 of this invention. It is a figure which shows the structure of the transmitting apparatus which concerns on Embodiment 5 of this invention. It is a figure which shows the structure of the transmitting apparatus which concerns on Embodiment 6 of this invention. It is a figure which shows the structure of the conventional receiver.

  Hereinafter, preferred embodiments of a receiver and a transmitter according to the present invention will be described with reference to the drawings.

Embodiment 1 FIG.
A receiver according to Embodiment 1 of the present invention will be described with reference to FIG. 1 is a diagram showing a configuration of a receiver according to Embodiment 1 of the present invention.

  1, a receiver according to Embodiment 1 of the present invention includes an antenna 1, a low noise amplifier 2, a signal distributor 3 that distributes a received signal, and a band-pass filter that removes unwanted waves in a high frequency band. (BPF) 4, a down converter 5 that converts the received high-frequency signal into a baseband signal, a mixer 6 that constitutes the down converter 5, a local oscillator 7 that constitutes the down converter 5, and input n + m signals A switch matrix (signal switching means) 8 for arbitrarily switching the output to k outputs, a low-pass filter (LPF) 9 for removing unnecessary waves in the baseband, and an A for converting an analog baseband signal into a digital signal A / D converter 10 and a digital unit 11 for signal processing are provided.

  Next, the operation of the receiver according to the first embodiment will be described with reference to the drawings.

  The receiver according to the first embodiment receives signals in a plurality of frequency bands, and the upper low-noise amplifier 2a supports n frequency bands including f1, f2 to fn as frequencies, The low noise amplifier 2b corresponds to m frequency bands composed of f1, f2 to fm as frequencies.

  The signals amplified by the low noise amplifiers 2a and 3b are distributed by the signal distributors 3a and 3b, passed through the bandpass filters 4 in the corresponding frequency bands, respectively, and then converted into baseband signals by the down converter 5 having n systems and m systems, respectively. Convert to

  Each down-converter 5 includes a mixer 6 and a local oscillator 7, and the baseband signal converted by the down-converter 5 is converted into a low-pass filter 9 and an A / D converter by a switch matrix 8 of (n + m): k. 10 is output to the k-system baseband circuit, and is output to the digital unit 11. In this receiver, a maximum of k signals are received simultaneously from n + m frequency bands.

  In the receiver according to the first embodiment, a switch matrix 8 for selecting and receiving and demodulating a maximum of k signals simultaneously from n + m frequency bands is provided in the subsequent stage of the down converter 5, that is, a baseband band. Therefore, it is easier to reduce signal loss in the switch matrix 8 and to secure isolation between the channels than in the case where it is provided in the previous stage of the down converter 5, that is, in the high frequency band. Further, since the loss of the switch matrix 8 is reduced, the signal-to-noise ratio as a receiver can be improved. Furthermore, when the down converter 5 has a gain, the signal-to-noise ratio can be further improved.

  In the first embodiment, the number of antennas 1 corresponds to two, but the number of antennas 1 is three or more, and a low noise amplifier 2, a signal distributor 3, and a down converter 5 are provided for each. In this case, the same effect can be obtained.

Embodiment 2. FIG.
A receiver according to Embodiment 2 of the present invention will be described with reference to FIG. FIG. 2 is a diagram showing a configuration of a receiver according to Embodiment 2 of the present invention.

  2, a receiver according to Embodiment 2 of the present invention includes an antenna 1, a low noise amplifier 2, a signal distributor 3 that distributes a received signal, and a band-pass filter that removes unwanted waves in a high frequency band. (BPF) 4, a mixer 6 that converts a high-frequency signal into a baseband signal, a switch matrix (signal switching means) 8 that arbitrarily switches input n + m signals to k outputs, and a baseband bandwidth A low-pass filter (LPF) 9 for removing unnecessary waves, an A / D converter 10 for converting an analog baseband signal into a digital signal, a digital unit 11 for signal processing, a distributor 12 for a local oscillation wave, A k-system common local oscillator 13 corresponding to a plurality of frequency bands is provided.

  The mixer 6, the local oscillation wave distributor 12, and the common local oscillator 13 constitute a down converter that converts the received high-frequency signal into a baseband signal.

  Next, the operation of the receiver according to the second embodiment will be described with reference to the drawings.

  The basic operation of the receiver according to the second embodiment is the same as that of the receiver according to the first embodiment, but in the first embodiment, all of the down converters 5 have local oscillators 7. In contrast, the second embodiment is characterized in that k common local oscillators 13 are provided.

The common local oscillator 13 supplies a local oscillation wave via the local oscillation wave distributor 12 to a mixer corresponding to the same frequency band among the mixers 6a _{1 to} 6b _m .

  The receiver according to the second embodiment can achieve the same effects as the receiver according to the first embodiment, and can reduce the size and cost of the receiver by using a common local oscillator. Can do.

Embodiment 3 FIG.
A receiver according to Embodiment 3 of the present invention will be described with reference to FIG. FIG. 3 is a diagram showing a configuration of a receiver according to Embodiment 3 of the present invention.

  3, a receiver according to Embodiment 3 of the present invention includes an antenna 1, a low noise amplifier 2, a signal distributor 3 that distributes a received signal, and a band-pass filter that removes unwanted waves in a high frequency band. (BPF) 4, a mixer 6 that converts a high-frequency signal into a baseband signal, a switch matrix (signal switching means) 8 that arbitrarily switches input n + m signals to k outputs, and a baseband bandwidth A variable bandpass filter (BPF) 14 capable of removing unnecessary waves and changing the passband, an A / D converter 10 that converts an analog baseband signal into a digital signal, a digital unit 11 for signal processing, and a local oscillation A wave distributor 12, a frequency synthesizer distributor 15 having a distribution ratio of 1: k, and a frequency synthesizer 16 capable of changing the output frequency are provided.

  The mixer 6, the local oscillation wave distributor 12, the frequency synthesizer distributor 15, and the frequency synthesizer 16 constitute a down converter that converts the received high-frequency signal into a baseband signal.

  Next, the operation of the receiver according to the third embodiment will be described with reference to the drawings.

The basic operation of the receiver according to the third embodiment is the same as that of the receiver according to the first and second embodiments. However, in this third embodiment, the local oscillation output from the frequency synthesizer 16 is used. After the waves are distributed to the k systems by the frequency synthesizer distributor 15, they are further distributed by the local oscillator wave distributor 12 and used as local oscillation sources for driving the mixers 6 a _{1 to} 6 b _m and are not required in the baseband band. It is characterized by using a variable bandpass filter 14 for wave removal.

In the receiver according to the third embodiment, since one frequency synthesizer 16 is used as a local oscillation source for driving the mixers 6a _{1 to} 6b _n , the mixer 6 uses the frequency of the received high-frequency signal and the local oscillation wave. Since IF signals with mixed frequencies are output and the frequencies of these IF signals differ with respect to the frequency of the received high-frequency signal, the band of the variable bandpass filter 14 is varied to correspond to each IF frequency. is there.

  The receiver according to the third embodiment achieves the same effect as the receiver according to the first and second embodiments described above, and realizes the local oscillator that drives the mixer 6 with one frequency synthesizer 16. Compared to the receivers according to the first and second embodiments, the size and cost can be further reduced.

Embodiment 4 FIG.
A transmitter according to Embodiment 4 of the present invention will be described with reference to FIG. FIG. 4 is a diagram showing a configuration of a transmitter according to Embodiment 4 of the present invention.

  4, a transmitter according to Embodiment 4 of the present invention includes an antenna 1, a high-power amplifier 17, a signal synthesizer 20 that synthesizes a transmission signal, and a band-pass filter that removes unnecessary waves in a high-frequency band. (BPF) 4, an up-converter 18 that converts an input baseband signal into a high-frequency signal, a mixer 6 that constitutes the up-converter 18, a local oscillator 7 that constitutes the up-converter 18, and k pieces of input A switch matrix (signal switching means) 8 that arbitrarily switches the signal to m + n outputs, a low-pass filter (LPF) 9 that removes unwanted waves in the baseband, and a digital signal that is converted into an analog baseband signal A D / A converter 19 and a digital unit 11 for signal processing are provided.

  Next, the operation of the transmitter according to the fourth embodiment will be described with reference to the drawings.

  The transmitter according to the fourth embodiment transmits signals in a plurality of frequency bands. The upper high-power amplifier 17a corresponds to n frequency bands including f1, f2 to fn as frequencies, and the lower stage. The high output amplifier 17b corresponds to m frequency bands consisting of f1, f2 to fm as frequencies.

  The baseband signals of the maximum k systems generated by the digital unit 11 are converted into analog baseband signals by the D / A converter 19, and unnecessary waves are removed by the low-pass filter 9, and then (n + m): k switch The matrix 8 outputs to the up-converter 18 corresponding to the desired transmission frequency in each signal.

  In this up-converter 18, the analog baseband signal input to the mixer 6 and the local oscillation wave input from the local oscillator 7 are mixed to convert the analog baseband signal into a high-frequency signal, which is unnecessary for the band-pass filter 4 in the high-frequency band. After the wave is removed, a plurality of high frequency signals are synthesized by the signal synthesizer 20, amplified to a desired power by the high output amplifier 17, and transmitted from the antenna 1.

  In the transmitter according to the fourth embodiment, the switch matrix 8 for transmitting a maximum of k signals is provided in the previous stage of the upconverter 18, that is, in the baseband, so that the subsequent stage of the upconverter 18, that is, the high frequency. Compared with the case where the band is provided, it is easy to reduce signal loss in the switch matrix 8 and to secure isolation between the channels.

  In the fourth embodiment, the number of antennas 1 is two, but the number of antennas 1 is three or more, and a high-power amplifier 17, a signal synthesizer 20, and an up converter 18 are provided for each. In this case, the same effect can be obtained.

Embodiment 5 FIG.
A transmitter according to Embodiment 5 of the present invention will be described with reference to FIG. FIG. 5 is a diagram showing a configuration of a transmitter according to Embodiment 5 of the present invention.

  In FIG. 5, a transmitter according to Embodiment 5 of the present invention includes an antenna 1, a high-power amplifier 17, a signal synthesizer 20 that synthesizes a transmission signal, and a band-pass filter that removes unnecessary waves in a high-frequency band. (BPF) 4, mixer 6, switch matrix (signal switching means) 8 for arbitrarily switching the input k signals to m + n outputs, and a low-pass filter for removing unnecessary waves in the baseband (LPF) 9, a D / A converter 19 for converting a digital signal into an analog baseband signal, a digital unit 11 for signal processing, a local oscillator distributor 12, and k systems corresponding to a plurality of frequency bands Common local oscillator 13 is provided.

  The mixer 6, the local oscillation wave distributor 12, and the common local oscillator 13 constitute an up-converter that converts the input baseband signal into a high-frequency signal.

  Next, the operation of the transmitter according to the fifth embodiment will be described with reference to the drawings.

  The basic operation of the transmitter according to the fifth embodiment is the same as that of the transmitter according to the fourth embodiment. However, in the fourth embodiment, all of the up-converters 18 use the local oscillator 7. In contrast to this, the fifth embodiment is characterized in that it includes k common local oscillators 13.

The common local oscillator 13 supplies a local oscillation wave via the local oscillation wave distributor 12 to a mixer corresponding to the same frequency band among the mixers 6a _{1 to} 6b _m .

  The transmitter according to the fifth embodiment can achieve the same effects as the receiver according to the fourth embodiment, and can reduce the size and cost of the transmitter by using a common local oscillator. Can do.

Embodiment 6 FIG.
A transmitter according to Embodiment 6 of the present invention will be described with reference to FIG. FIG. 6 is a diagram showing a configuration of a transmitter according to Embodiment 6 of the present invention.

  6, a transmitter according to Embodiment 6 of the present invention includes an antenna 1, a high-power amplifier 17, a signal synthesizer 20 that synthesizes a transmission signal, and a band-pass filter that removes unnecessary waves in a high-frequency band. (BPF) 4, mixer 6, switch matrix (signal switching means) 8 for arbitrarily switching the input k signals to m + n outputs, unnecessary waves in the baseband band are removed, and the passband is A variable bandpass filter (BPF) 14 that can be changed, a D / A converter 19 that converts a digital signal into an analog baseband signal, a digital unit 11 for signal processing, and a local oscillator distributor 12: A frequency synthesizer distributor 15 having a distribution ratio of k and a frequency synthesizer 16 capable of changing the output frequency are provided.

  The mixer 6, the local oscillation wave distributor 12, the frequency synthesizer distributor 15, and the frequency synthesizer 16 constitute an up converter that converts an input baseband signal into a high-frequency signal.

  Next, the operation of the transmitter according to the sixth embodiment will be described with reference to the drawings.

The basic operation of the transmitter according to the sixth embodiment is the same as that of the transmitter according to the fourth and fifth embodiments. However, in this sixth embodiment, local oscillation output from the frequency synthesizer 16 is performed. After the waves are distributed to the k systems by the frequency synthesizer distributor 15, they are further distributed by the local oscillator wave distributor 12 and used as local oscillation sources for driving the mixers 6 a _{1 to} 6 b _m and are not required in the baseband band. It is characterized by using a variable bandpass filter 14 for wave removal.

In the transmitter according to the sixth embodiment, since one frequency synthesizer 16 is used as a local oscillation source for driving the mixers 6a _{1 to} 6b _m , the mixer 6 uses the frequency of the received high-frequency signal and the local oscillation wave. Since IF signals with mixed frequencies are output and the frequencies of these IF signals differ with respect to the frequency of the received high-frequency signal, the band of the variable bandpass filter 14 is varied to correspond to each IF frequency. is there.

  The transmitter according to the sixth embodiment achieves the same effects as the receivers according to the fourth and fifth embodiments described above, and realizes the local oscillator that drives the mixer 6 with one frequency synthesizer 16. Compared to the transmitters according to the fourth and fifth embodiments, it is possible to further reduce the size and cost.

  1 antenna, 2 low noise amplifier, 3 signal distributor, 4 band pass filter, 5 down converter, 6 mixer, 7 local oscillator, 8 switch matrix, 9 low pass filter, 10 A / D converter, 11 digital section, 12 Local oscillator distributor, 13 Common local oscillator, 14 Variable bandpass filter, 15 Frequency synthesizer distributor, 16 Frequency synthesizer, 17 High power amplifier, 18 Up converter, 19 D / A converter, 20 Signal synthesizer.

Claims (6)

A plurality of antennas for receiving a plurality of high frequency signals;
A plurality of low noise amplifiers for amplifying high frequency signals received by the plurality of antennas;
A plurality of signal distributors for distributing the output signals of the plurality of low noise amplifiers;
A plurality of bandpass filters for removing unwanted waves from the output signals of the plurality of signal distributors;
A plurality of downconverters each comprising a local oscillator and a mixer for converting the received high frequency signal into a baseband signal;
A signal switching means connected to the plurality of down converters for switching a plurality of input signals to a plurality of output signals;
A plurality of low pass filters connected to the signal switching means for removing unwanted waves in the baseband signal band;
A receiver comprising: a plurality of A / D converters that convert baseband signals from the plurality of low-pass filters into digital signals. 2. The receiver according to claim 1, wherein a local oscillator constituting a down converter is made common for each frequency band to be received, and a plurality of local oscillation waves are supplied to a plurality of mixers by a plurality of local oscillation wave distributors. All local oscillators composing the down converter are made common, and local oscillation waves are supplied to a plurality of mixers by a plurality of local oscillation wave distributors, and the low-pass filter of the baseband signal band is changed to a variable band-pass filter. The receiver according to claim 1, wherein each receiver is replaced. A plurality of D / A converters for converting digital signals into analog baseband signals;
A plurality of low-pass filters for removing unwanted waves in the baseband signal band;
A signal switching unit connected to the plurality of low-pass filters and switching a plurality of input signals to a plurality of output signals;
A plurality of up-converters connected to the signal switching means, each of which is composed of a local oscillator and a mixer, and which converts an input baseband signal into a high-frequency signal;
A plurality of band pass filters for removing unwanted waves in the high frequency signal band; and
A plurality of signal synthesizers for synthesizing output signals of the plurality of bandpass filters;
A plurality of high power amplifiers for amplifying high frequency signals from the plurality of signal synthesizers;
A plurality of antennas for transmitting a plurality of high frequency signals from a plurality of high power amplifiers;
A transmitter characterized by comprising: 5. The transmitter according to claim 4, wherein the local oscillator constituting the up-converter is shared for each frequency band to be transmitted, and the local oscillation waves are supplied to the plurality of mixers by the plurality of local oscillation wave distributors. All local oscillators composing the up-converter are made common, and local oscillation waves are supplied to a plurality of mixers by a plurality of local oscillation wave distributors, and the low-pass filter of the baseband signal band is changed to a variable band-pass filter. The transmitter according to claim 4, wherein each of the transmitters is replaced.

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