CN106571839A - Radio frequency signal source using FPGA - Google Patents
Radio frequency signal source using FPGA Download PDFInfo
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- CN106571839A CN106571839A CN201610995145.9A CN201610995145A CN106571839A CN 106571839 A CN106571839 A CN 106571839A CN 201610995145 A CN201610995145 A CN 201610995145A CN 106571839 A CN106571839 A CN 106571839A
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- frequency
- fpga
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- signal generator
- baseband signals
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/02—Transmitters
- H04B1/04—Circuits
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- Computer Networks & Wireless Communication (AREA)
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Abstract
The invention discloses a radio frequency signal source using FPGA. The radio frequency signal source comprises an FPGA baseband signal modulator, an intermediate frequency modulation signal generator, a mixer, a radio frequency local oscillator signal generator, a radio frequency medium filter and an output port. The FPGA baseband signal modulator, the intermediate frequency modulation signal generator, the mixer, the radio frequency medium filter and the output port are connected in turn. The FPGA baseband signal modulator, the radio frequency local oscillator signal generator and the mixer are connected in turn. The FPGA baseband signal modulator and the radio frequency medium filter are connected. According to the invention, the radio frequency signal generating system which generates 2.4GHz frequency band can meet the use needs of research and teaching instruments, is suitable for increasingly wide applications such as wireless communication and a wireless local area network, has the advantages of low cost, simple external circuit, stable working frequency band, adjustable parameter and friendly man-machine interface, and has operation as convenient as an ordinary signal generator.
Description
Technical field
The present invention relates to radiofrequency signal field, and in particular to a kind of radio-frequency signal source of application FPGA.
Background technology
In modern wireless communication systems, higher and higher requirement is proposed to Large Copacity, being wirelessly transferred for high-speed data, perhaps
It is multi-vendor also to release based on the RFCO2 laser of 802.11 serial protocols, and the technology such as wireless router, bluetooth also extensively applies, it is right
The use demand of 2.4GHz frequency ranges is increasing, but except the signal that part high-side signal generator has 2.4GHz frequency ranges is produced
Raw, ordinary signal generation is not directed to 2.4GHz frequency ranges, and exploitation is related to a kind of radiofrequency signal based on 2.4GHz frequency ranges to be occurred
Device is meeting the needs that scientific research and instruments used for education are used.
The content of the invention
The technical problem to be solved is that ordinary signal generation is not directed to 2.4GHz frequency ranges, it is impossible to meet section
Grind and needs that instruments used for education are used.Purpose is to provide a kind of radio-frequency signal source of application FPGA, produces 2.4GHz frequency ranges
There is system to meet the needs that scientific research and instruments used for education are used in radiofrequency signal.
The present invention is achieved through the following technical solutions：
A kind of radio-frequency signal source of application FPGA, including FPGA modulates baseband signals devices, modulated intermediate frequency signal generator, mixing
Device, RF local oscillator signal generator, frequency medium wave filter and output port, the FPGA modulates baseband signals device, middle frequency modulation
Signal generator processed, frequency mixer, frequency medium wave filter, output port are sequentially connected, and the FPGA modulates baseband signals device, penetrate
Frequency local oscillation signal generator, frequency mixer are sequentially connected, and the FPGA modulates baseband signals device and frequency medium wave filter connect；Institute
FPGA modulates baseband signals device is stated for producing baseband signal, modulated intermediate frequency signal generator is used for modulates baseband signals in
Frequency signal, the RF local oscillator signal generator is used to produce RF local oscillator signal, the frequency mixer be used for intermediate-freuqncy signal and
RF local oscillator signal is mixed into radiofrequency signal, and the frequency medium wave filter is used to be filtered baseband signal and radiofrequency signal
Ripple.The intermediate-freuqncy signal that modulated intermediate frequency signal generator is produced is 70MHz, and frequency mixer penetrates the modulation of 70M intermediate-freuqncy signals to 2.4GHz
Frequency signal.FPGA modulates baseband signals devices are also associated with man machine interface, can realize man-machine interaction by man machine interface.
Further, modulated intermediate frequency signal generator includes deserializer, analog-digital chip, coupled RF transformation
Device, SAW filter and intermediate frequency amplifier, the FPGA modulates baseband signals device, deserializer, analog-digital chip,
Coupled RF transformator, SAW filter, intermediate frequency amplifier, frequency mixer are sequentially connected.Analog-digital chip inside includes
Quadrature modulator, digital to analog converter, DDS kernels, deserializer is connected with quadrature modulator, and FPGA modulates baseband signals device will
Control word is input into DDS kernels, and with reference to clock signal DDS kernels are also input into, and DDS kernels are connected with quadrature modulator, orthogonal
Manipulator is connected with digital to analog converter, and digital to analog converter is connected with coupled RF transformator.
Further, RF local oscillator signal generator includes with reference to crystal oscillator, frequency synthesizer, low pass filter, voltage-controlled shakes
Device is swung, the FPGA modulates baseband signals device, frequency synthesizer, low pass filter, voltage controlled oscillator are sequentially connected, VCO
Device is connected with frequency synthesizer, and the reference crystal oscillator is connected with FPGA modulates baseband signals devices.Frequency mixer is by the intermediate frequency of 70MHz
Signal is mixed to the radiofrequency signal of the ISM band of 2450MHz, and RF local oscillator signal is necessary, and frequency is 2380MHz.
Further, a kind of radio-frequency signal source of application FPGA, also including controllable gain power amplifier, the controllable gain
Power amplifier is arranged on the circuit between frequency medium wave filter and output port, for what is exported to frequency medium wave filter
Signal is amplified.
The present invention compared with prior art, has the following advantages and advantages：The generation 2.4GHz of present invention design
The radiofrequency signal of frequency range occurs system can meet the needs that scientific research and instruments used for education are used；Meet simultaneously and apply increasingly extensive nothing
Line communication, WLAN etc. are applied, and its low cost, peripheral circuit are simple, and working band is stable, Parameter adjustable, man machine interface
Close friend, facilitates as operation ordinary signal generation.
Description of the drawings
Accompanying drawing described herein is used for providing further understanding the embodiment of the present invention, constitutes of the application
Point, do not constitute the restriction to the embodiment of the present invention.In the accompanying drawings：
Fig. 1 is present system circuit theory schematic diagram；
Fig. 2 is modulated intermediate frequency signal generator architecture schematic diagram of the present invention；
Fig. 3 is RF local oscillator signal generator structural representation of the present invention；
Fig. 4 is mixer figure of the present invention.
Specific embodiment
To make the object, technical solutions and advantages of the present invention become more apparent, with reference to embodiment and accompanying drawing, to this
Invention is described in further detail, and the exemplary embodiment of the present invention and its explanation are only used for explaining the present invention, do not make
For limitation of the invention.
Embodiment
As shown in figure 1, a kind of radio-frequency signal source of application FPGA, including FPGA modulates baseband signals devices, intermediate frequency Modulation letter
Number generator, frequency mixer, RF local oscillator signal generator, frequency medium wave filter and output port, FPGA modulates baseband signals
Device, modulated intermediate frequency signal generator, frequency mixer, frequency medium wave filter, output port are sequentially connected, FPGA modulates baseband signals
Device, RF local oscillator signal generator, frequency mixer are sequentially connected, and FPGA modulates baseband signals device and frequency medium wave filter connect；
FPGA modulates baseband signals device is used to produce baseband signal, and modulated intermediate frequency signal generator is used for modulates baseband signals into intermediate frequency
Signal, RF local oscillator signal generator is used to produce RF local oscillator signal, and frequency mixer is used to believe intermediate-freuqncy signal and RF local oscillator
Radiofrequency signal number is mixed into, frequency medium wave filter is used to be filtered baseband signal and radiofrequency signal.FPGA baseband signals
Manipulator produces baseband signal and by base band signal transmission to modulated intermediate frequency signal generator, RF local oscillator signal generator and penetrates
Frequency dielectric filter, modulated intermediate frequency signal generator transmits modulates baseband signals to mixing into intermediate-freuqncy signal and by intermediate-freuqncy signal
Device, RF local oscillator signal generator produces RF local oscillator signal and transmits it to frequency mixer, and frequency mixer believes the intermediate frequency for receiving
Number and RF local oscillator signal be mixed city radiofrequency signal, frequency mixer is by radio signal transmission to frequency medium wave filter, frequency medium
Wave filter is put by controllable gain power amplifier after being filtered the baseband signal and radiofrequency signal of reception to signal
Transmit to output port after big.
As shown in Fig. 2 modulated intermediate frequency signal generator includes deserializer, analog-digital chip, coupled RF transformation
Device, SAW filter and intermediate frequency amplifier, FPGA modulates baseband signals devices, deserializer, analog-digital chip, coupling
Radio-frequency transformer, SAW filter, intermediate frequency amplifier, frequency mixer are sequentially connected.FPGA modulates baseband signals device is by base band
Signal transmission to deserializer carries out serioparallel exchange, and the signal transmission after serioparallel exchange to analog-digital chip is carried out
Digital-to-analogue conversion, the signal after digital-to-analogue conversion passes sequentially through coupled RF transformator, SAW filter and intermediate frequency and puts
Big device carries out process and forms intermediate-freuqncy signal and export to frequency mixer.FPGA modulates baseband signals device is using ALTERA companies
EP1C20 chips, analog-digital chip adopts AD9856, and the i/q signal that FPGA modulates baseband signals device is produced is via serioparallel exchange
Send into afterwards in AD9856, the DDS kernels inside AD9856, orthogonal local oscillation signal is produced by FPGA controls and sends into positive intermodulation
Device processed, is added after being multiplied with i/q signal respectively by 2 grades, produces orthogonal demodulation signal, and specific modulating mode can lead to
The baseband signal coding mapping design of FPGA is crossed, finally by the analog difference signal output that 12 DAC are changed into orthogonal modulation, is connect
And the differential signal of output is converted to into single-ended signal with coupled RF transformator, filter via the SAW filter of 70MHz
Ripple, finally carries out signal amplification from intermediate frequency amplifier, so that it may which sending into frequency mixer carries out being mixed.
As shown in figure 3, RF local oscillator signal generator includes with reference to crystal oscillator, frequency synthesizer, low pass filter, voltage-controlled shakes
Swing device, FPGA modulates baseband signals devices, frequency synthesizer, low pass filter, voltage controlled oscillator are sequentially connected, voltage controlled oscillator with
Frequency synthesizer connects, and is connected with FPGA modulates baseband signals devices with reference to crystal oscillator.FPGA modulates baseband signals device Jing baseband signals
Transmitting to frequency synthesizer carries out frequency synthesis, and the signal after frequency synthesis is filtered through low pass filter and transmits to pressure
Controlled oscillator, voltage controlled oscillator carries out processing and produces RF local oscillator signal and export to frequency mixer to the signal after filtering.Penetrate
Frequency local oscillation signal generator provides local oscillation signal using the phase-locked loop of PLL+VCO, with precision and degree of stability height, changeable frequency
The advantages of, convenient frequency resource afterwards is adjusted or extended.The frequency stability of local oscillation signal is critically important, and this part is designed to collect
It is core into circuit, using the voltage controlled oscillator MAX2750 of the frequency synthesizer ADF4113 and MAXIM companies of ADI companies.For
Control frequency synthesizer controls phase-locked loop frequency synthesizer ADF4113 by FPGA serial interface signals sequential, according to
The ratio with reference to the frequency of crystal oscillator and frequency (Jing the removes Fractional-N frequency device) phase contrast of voltage controlled oscillator (VCO) is completed inside ADF4113
Compared with, and corresponding Linear voltage output is converted into, after low-pass filtered device (LPF) is considered except High-frequency Interference, obtain one more steady
Fixed voltage, controls the frequency of oscillation output of VCO, so as to obtain required 2380MHz local oscillation signals.
The circuit of frequency mixer is mainly completed 70M as shown in figure 4, frequency mixer is realized particularly important to 2.4GHz frequency ranges
Intermediate-freuqncy signal modulation is mixed chip from the MAX2671 of the special 2.4GHz frequency ranges of MAXIM companies here to 2.4GHz radio frequencies.
Wherein, the input signal of pin L0 is oscillator signal, and pin IFIN is intermediate frequency output, and resistance R1 is shutdown control end,
The outfan of electric capacity C4 is RF signal output.MAX2671 allows intermediate frequency incoming frequency between 40MHz to 500MHz, penetrates
Frequency output frequency is between 2.4GHz to 2.5GHz.Using single-ended signal, a single pass multiplier is internally integrated,
During the radiofrequency signal mixing output of 2450MHz, the gain with 8.9dB, therefore, local oscillation signal is arrived between+5dBm in -10dBm
.Each component parameter is as follows in circuit：Electric capacity C1-220pF；Electric capacity C2-220pF；Electric capacity C3-220pF；Electric capacity C4-
220pF；Electric capacity C6-47pF；Electric capacity C8-100pF；Electric capacity C9-10uF；Inductance L1-1.8nH；Inductance L2-3.3nH.
Specific embodiment above, has been carried out further in detail to the purpose of the present invention, technical scheme and beneficial effect
Illustrate, should be understood that the specific embodiment that these are only the present invention, the protection model being not intended to limit the present invention
Enclose, all any modification, equivalent substitution and improvements within the spirit and principles in the present invention, done etc. should be included in the present invention
Protection domain within.
Claims (4)
1. a kind of radio-frequency signal source of application FPGA, it is characterised in that including FPGA modulates baseband signals devices, modulated intermediate frequency signal
Generator, frequency mixer, RF local oscillator signal generator, frequency medium wave filter and output port, the FPGA baseband signals are adjusted
Device processed, modulated intermediate frequency signal generator, frequency mixer, frequency medium wave filter, output port are sequentially connected, the FPGA base band letter
Number manipulator, RF local oscillator signal generator, frequency mixer are sequentially connected, and the FPGA modulates baseband signals device and frequency medium are filtered
Ripple device connects；The FPGA modulates baseband signals device is used to produce baseband signal, and modulated intermediate frequency signal generator is used for base band
Into intermediate-freuqncy signal, the RF local oscillator signal generator is used to produce RF local oscillator signal signal modulation, and the frequency mixer is used for
Intermediate-freuqncy signal and RF local oscillator signal are mixed into into radiofrequency signal, the frequency medium wave filter is used for baseband signal and radio frequency
Signal is filtered.
2. a kind of radio-frequency signal source of application FPGA according to claim 1, it is characterised in that the modulated intermediate frequency signal
Generator includes deserializer, analog-digital chip, coupled RF transformator, SAW filter and intermediate frequency amplifier,
The FPGA modulates baseband signals device, deserializer, analog-digital chip, coupled RF transformator, SAW filter,
Intermediate frequency amplifier, frequency mixer are sequentially connected.
3. a kind of radio-frequency signal source of application FPGA according to claim 1, it is characterised in that the RF local oscillator signal
Generator is included with reference to crystal oscillator, frequency synthesizer, low pass filter, voltage controlled oscillator, the FPGA modulates baseband signals device, frequency
Rate synthesizer, low pass filter, voltage controlled oscillator are sequentially connected, and voltage controlled oscillator is connected with frequency synthesizer, described with reference to brilliant
Shake and be connected with FPGA modulates baseband signals devices.
4. the radio-frequency signal source of a kind of application FPGA according to claim 1, it is characterised in that also including controllable gain work(
Electric discharge road, the controllable gain power amplifier is arranged on the circuit between frequency medium wave filter and output port, for right
The signal of frequency medium wave filter output is amplified.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610995145.9A CN106571839A (en) | 2016-11-11 | 2016-11-11 | Radio frequency signal source using FPGA |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610995145.9A CN106571839A (en) | 2016-11-11 | 2016-11-11 | Radio frequency signal source using FPGA |
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| Publication Number | Publication Date |
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| CN106571839A true CN106571839A (en) | 2017-04-19 |
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| CN201610995145.9A Pending CN106571839A (en) | 2016-11-11 | 2016-11-11 | Radio frequency signal source using FPGA |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108123763A (en) * | 2017-12-26 | 2018-06-05 | 中国铁路信息技术中心 | Frequency difference compensation method and device |
| CN109302241A (en) * | 2017-12-12 | 2019-02-01 | 上海创远仪器技术股份有限公司 | A kind of vector signal generation device and method based on chip |
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Cited By (3)
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| CN109302241A (en) * | 2017-12-12 | 2019-02-01 | 上海创远仪器技术股份有限公司 | A kind of vector signal generation device and method based on chip |
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| CN108123763A (en) * | 2017-12-26 | 2018-06-05 | 中国铁路信息技术中心 | Frequency difference compensation method and device |
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Application publication date: 20170419 |