KR101386551B1 - M-psk modulator and demodulator using multiple spin oscillators - Google Patents

Abstract

The present invention relates to an M-PSK demodulator using a plurality of spin demodulators which comprises: a spin demodulator device including a plurality of spin demodulators that outputs oscillation signals in which a phase is discrete distributed; a phase selector for outputting the phase information of the oscillation signals of the phase closest to a modulated signal by comparing the phase of the oscillation signals with received modulated signals; and a determination part for determining restoration data from the phase information on the basis of at least one determination line of being controlled by operating environment. [Reference numerals] (10) Spin oscillator device; (5) Low pass filter; (6) Selector; (7) Determination part; (8) Phase selector

Description

 M-PSK modulator and demodulator using multiple spin oscillators}

The present invention relates to an M-PSK modulator and a demodulator using a plurality of spin oscillators. More particularly, the present invention relates to generating a plurality of oscillation signals having various phases by using a plurality of spin oscillators. Transmit the oscillation signal of the corresponding phase as a phase modulated signal, generate oscillation signals with various phases to detect the phase of the received modulated signal, extract the oscillation signal with the smallest phase difference compared with the modulated signal, and extract the corresponding phase An M-PSK modulator and a demodulator using a plurality of spin oscillators for determining restoration data through at least one decision line.

Phase shift keying (hereinafter referred to as 'PSK') is a method of carrying data on a high frequency carrier, of which binary phase shift keying (hereinafter, referred to as 'BPSK'). ) Is a method of transmitting a digital signal of two values (0 or 1) to be transmitted corresponding to the zero phase and the π phase of the carrier.

1 is a block diagram of an 8-PSK modulator according to the prior art, which includes an I channel level converter 32, an inverter 33, a Q channel level converter 34, a reference oscillator 38, a first mixer 36, A second mixer 39, a phase shifter 35, a first band pass filter 37, a second band pass filter 41, a third mixer 40, and a third band pass filter 42. .

값이 Q 채널 레벨 컨버터(34)로 인가된다. I 채널 레벨 컨버터(32)의 출력은 표 1과 같다.The I value and C value among the 3 bits of the input data are supplied to the I channel level converter 32, and the Q value and

The value is applied to the Q channel level converter 34. The output of the I channel level converter 32 is shown in Table 1.

I C PAM1 0 0 -0.541V 0 One -1.307V One 0 + 0.541V One One + 1.307V

The output of the Q channel level converter 34 is shown in Table 2.

Q

PAM2 0 0 -1.307V 0 One -0.541V One 0 + 1.307V One One + 0.541V

The Q channel level and the signal passing through the first band pass filter 37 after multiplying the output PAM1 of the I channel level converter 32 by the sinusoidal wave sin (2πf _c t) from the reference oscillator 38 The output PAM2 of the converter 34 is multiplied by the sine wave (cos (2πf _c t)) from the reference oscillator 38, and then multiplied by the signal passing through the second band pass filter 41, and then the third band. Pass pass filter 42 to generate an 8-PSK modulated signal (8-PSK Output). FIG. 3 is a constellation point of a modulated signal output from the modulator shown in FIG. 2.

The PSK modulator according to the prior art uses an oscillator having a high Q value or a phase locked loop (PLL) because the frequency and phase of the sine wave output from the reference oscillator must be accurately fixed. There is a problem.

Meanwhile, in order to demodulate a signal modulated by the BPSK scheme, a method of generating a sinusoidal wave having the same frequency as the transmission wave and multiplying the transmitted signal may be used. In general, however, an error may occur in the demodulation process because the sine wave generated internally and the sine wave generated internally are not synchronized with each other.

To compensate for this, analog demodulators are commonly used, called the Costas loop. This method uses negative feedback to recover an error of the demodulated signal due to the phase difference between the signal transmitted during synchronization and the sine wave generated inside the demodulator.

 FIG. 2 illustrates a Costas loop according to the prior art, and includes a first mixer 110 to a third mixer 130, a first low pass filter (LPF) 120, and a second low pass filter ( 170, a loop filter 140, and a voltage controlled oscillator 150 (hereinafter, referred to as a 'VCO'). The first mixer 110 multiplies the modulation signal m (t) cos (ωt) received from the outside through an antenna and the first sinusoidal signal cos (ωt + θ) output from the VCO 150. Output to the first low pass filter 120. The second mixer 160 multiplies the modulated signal m (t) cos (ωt) by a second sinusoidal wave signal sin (ωt + θ), which is an oscillation signal output from the VCO 150, to thereby obtain the second low pass. Output to the pass filter 170. If the output signal of the VCO 150 has a phase difference of θ with respect to the carrier of the transmitter, the output signals of the first mixer 110 and the second mixer 160 are represented by Equations 1 and 2, respectively. .

The first low pass filter 120 and the second low pass filter 170 filter noise signals of a high frequency band from output signals of the first mixer 110 and the second mixer 160, respectively, Passes only the signal and amplifies the input signal twice. Accordingly, the signals output from the first low pass filter 120 and the second low pass filter 170 are m (t) cosθ and m (t) sinθ, respectively. The third mixer 130 multiplies the output signals of the first low pass filter 120 and the second low pass filter 170 and applies them to the loop filter 140. The output of the third mixer 130 is converted into a predetermined voltage in the loop filter 140 and then applied to the VCO 150. VCO 150 obtains θ from the output of loop filter 140 and generates an oscillation signal that oscillates at θ angle. The oscillation signal and the second sinusoidal wave signal having a phase difference of 90 ° from the oscillation signal are applied to the first mixer 110 and the second mixer 160, respectively.

The demodulator according to the prior art has a high accuracy, but there are problems in that the size of the product is large and the power consumption is high because it uses complicated and many analog circuits including a VCO. In order to solve this problem, there is a method of applying a spin-transfer torque type device that can replace an oscillator with a single device in a nanoscale unit. The spin transfer torque type device generates an oscillation signal having a specific frequency component when a voltage or current is applied, and outputs an oscillation signal of various frequency bands by adjusting the applied current or voltage. High speed transmission of high capacity data is possible for communication. However, the spin-transfer torque type device has a problem in that the line width, that is, the Q value, is poor in current technology, so that the phase noise characteristic is poor and the oscillation signal which is linearly proportional to the applied voltage or current cannot be output. A single spin torque device does not oscillate at a constant frequency, which makes it unreasonable for current technology to use it as a demodulator.

Patent Document 1 discloses a BPSK demodulation apparatus including a reception signal processing unit, an absolute value comparison unit, and a demodulation unit for reducing complexity and power consumption. The reception signal processing unit receives an input signal and outputs a first low- And the absolute value comparison section provides a comparison signal having a logic level based on the magnitude of the absolute values of the first and second low-band signals, wherein the demodulation section digitally converts the first and second low-band signals, respectively, And outputs either one of the first converted signal and the second converted signal digitally converted to the first demodulated signal according to the logical level of the signal.

Korean Registered Patent No. 1022419 (registered on March 08, 2011)

In order to solve the above problems, an oscillation signal having a stable and fixed frequency can be generated while generating various phase oscillation signals through a spin oscillator device, while reducing circuit complexity compared to a conventional demodulator using a high performance reference oscillator. Generate an oscillation signal having a phase corresponding to the data among the oscillation signals, selectively outputting the oscillation signal from the spin oscillator device as a phase modulation signal, and outputting the oscillation signal having a phase that most closely matches the phase of the modulation signal during demodulation to the spin oscillator device. Phase demodulated by various oscillation signals, and then demodulating data that compensates for phase offset and frequency offset through a variation determination line to provide a demodulator using a plurality of spin oscillators with small volume, low complexity, and low power consumption. The purpose.

M-PSK modulator using a plurality of spin oscillator according to the present invention for solving the above problems includes a spin oscillator device and a plurality of spin oscillator for outputting the oscillation signals of the phase distribution discretely and the spin oscillator according to the input data And an oscillator selector for selecting an oscillation signal having a phase corresponding to 1: 1 to the input data from the device and outputting the oscillation signal as a phase modulated signal.

In one preferred embodiment of the present invention, the spin oscillator device, RF power for outputting an RF signal, a plurality of delay blocks for outputting a signal of various delayed phase of the RF signal and the RF output from each delay block And a plurality of spin oscillators for receiving signals that are delayed in phase than the signals as respective input signals and driving the signals.

In one preferred embodiment of the present invention, the oscillator selector is a decoder, a mux or a switching circuit for receiving one of the oscillation signals output from the plurality of spin oscillator receives the binary data as a control signal It features.

In a preferred embodiment of the present invention, the plurality of spin oscillators are characterized in that the output signals from the plurality of delay blocks are injected by an injection fixed method to output the phase-tuned oscillation signals.

In one preferred embodiment of the present invention, the apparatus may further include a constant current supply circuit for supplying a constant current to the plurality of spin oscillators to output oscillation signals having the same frequency or 1/2 frequency as the RF signal.

In a preferred embodiment of the present invention, the plurality of delay blocks are capacitor arrays.

In still another embodiment of the present invention, a M-PSK demodulator using a plurality of spin oscillators according to the present invention includes a spin oscillator device including a plurality of spin oscillators for outputting phase-distributed oscillation signals, and a received modulation signal. A phase selector for comparing phases of the plurality of oscillation signals and outputting phase information of an oscillation signal having a phase closest to the modulation signal, and reconstructed data from the phase information on the basis of at least one decision line that is variably adjusted according to an operating environment And a judging section for judging.

In a preferred embodiment of the present invention, the determination unit is a determination line for t _{k +1} if the phase value of t _k time is clockwise than the reference phase θ _p (t _k ) of the determination line as the phase offset exists. Is moved clockwise, and if the phase value of t _k time is counterclockwise than the reference phase θ _p (t _k ) of the determination line, the counterclockwise movement is performed.

According to a preferred embodiment of the present invention, the determination unit updates phase information applied in real time from the phase selector to the determination line as a frequency offset exists, and determines reconstruction data based on the determination line that is changed in real time. It is done.

According to an exemplary embodiment of the present invention, the phase selector may include a mixer block for outputting a plurality of signals by multiplying the modulation signal and the plurality of oscillation signals individually, and a plurality of cosines by low pass filtering the outputs of the mixer block. and a selector for outputting a phase of a cosine signal corresponding to a maximum value of the plurality of cosine signals.

In another embodiment of the present invention, the M-PSK demodulation method using a plurality of spin oscillators according to the present invention comprises generating multi-phase discrete oscillation signals to separately multiply the received modulation signal with the oscillation signals, wherein And performing low pass filtering of multiplication signals and applying phase information of a signal selected as a maximum value of the low pass filtered signals to a determination unit, and determining reconstruction data from the phase information based on a determination line. It features.

In a preferred embodiment of the present invention, the applying of the phase information to the determining unit further includes the step of compensating for the phase offset by rotating the determination line clockwise by the phase offset angle if the phase offset exists. It features.

In a preferred embodiment of the present invention, the step of applying the phase information to the determination unit further comprises the step of compensating for the frequency offset by changing the real-time determination line in accordance with the reference phase and the applied phase information, if there is a frequency offset Characterized in that.

In a preferred embodiment of the present invention, the step of compensating the phase offset may include determining a determination line for t _{k +1} if a phase value of t _k time is in a clockwise direction than the reference phase θ _p (t _k ) of the determination line. Is moved clockwise, and if the phase value of t _k time is counterclockwise than the reference phase θ _p (t _k ) of the determination line, the counterclockwise movement is performed.

In a preferred embodiment of the present invention, the step of determining the reconstruction data from the phase information, further comprising the step of outputting a signal obtained by cosine the difference between the reference phase and the comparison phase from the phase information as a demodulation signal; It is characterized by.

Since the present invention can further refine the phase by increasing the number of spin oscillators, M-PSK modulators of BPSK or more can be implemented without using complicated circuits, and thus a high performance demodulator can be implemented that is superior to the prior art in high capacity data modulation. In addition, the present invention can obtain the oscillation signal having a significantly improved Q value by preventing the frequency variation of the oscillation signals by the spin oscillator device implemented by a plurality of spin oscillators.

The present invention can modulate data using various phase oscillation signals generated by a plurality of spin oscillators without outputting an oscillation signal linearly proportional to the voltage or current applied to the spin oscillator.

In the present invention, since the frequency can be varied only by applying the DC power supply by the spin oscillator, the frequency range can be used widely and less signal distortion occurs because it has less complexity than the conventional demodulator.

Since the demodulator of the prior art includes a phase-locked loop, if the phase is out of the synchronized state by paging, demodulation is inhibited for the time it takes for the phase to be fixed, and thus the demodulation characteristic is deteriorated. The demodulator using the spin oscillator can perform demodulation even at the time when paging occurs.

The present invention can be applied to Bluetooth and near field communication. Due to the use of spin torque devices, miniaturization and low power consumption can solve the problem of the existing Bluetooth-based and short-range communication, which consumes a lot of power and is large in size and reduced in portability due to the weight of the battery.

1 is a block diagram of a prior art 8-PSK modulator
2 is a block diagram of a conventional Costas loop demodulator
3 is a constellation point of an 8-PSK modulated signal by the modulator shown in FIG.
4 is an M-PSK modulator using a plurality of spin oscillators according to the present invention.
5 is an M-PSK demodulator using a plurality of spin oscillators according to the present invention.
FIG. 6 is a detailed configuration diagram of the spin oscillator device shown in FIGS. 4 and 5.
7 is a constellation point of one example of a modulated signal in accordance with the present invention.
8 is a view for explaining a determination method through a determination line of the determination unit illustrated in FIG. 5.
9 is a view for explaining a determination method through a determination line of the determination unit illustrated in FIG. 5.
10 is a view showing an embodiment of a spin torque type device applicable to the present invention
11 is a flowchart illustrating a demodulation method using a plurality of spin oscillators according to the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The drawings illustrate only the essential features of the invention in order to facilitate clarity of the invention and are not to be construed in a limiting sense since they are not shown in the accompanying drawings.

4 is a block diagram of an M-PSK modulator using a plurality of spin oscillators according to the present invention, which includes an oscillator selector 1 and a spin oscillator device 10.

The oscillator selector 1 selects an oscillation signal having a phase corresponding to 1: 1 to the data to be applied from the spin oscillator device 10 and outputs it as an M-PSK phase modulated signal. For example, referring to FIG. 7, data input to the oscillator selector 1 during 8-PSK modulation is 3 bits, 000 to 111. If the data is 000, the spin oscillator 12 that outputs the oscillation signal O ₁ (t) having a phase of 0 rad is selected from the spin oscillator device 10 and output as a modulated signal. A spin oscillator 14 that outputs an oscillation signal O ₈ (t) of 7π / 4 rad is selected from the spin oscillator device 10 and output as a phase modulation signal M-PSK. For example, M-PSK modulation includes M spin oscillators.

The oscillator selector 1 is located at the front end of the spin oscillator device 10 in FIG. 4 but may be located at the rear end in some cases. For example, the oscillator selector 1 receives binary data as a control signal and outputs oscillation signals O ₁ (t), O ₂ (t), ..., which are output from the spin oscillator device 10. O _M (t)) may be implemented as a decoder, a mux, or a switching circuit for selecting one of the oscillation signals. When implemented as a decoder, for example, if the input data is 111, the oscillation signal of the eighth spin oscillator is selected by the decoder and output as a phase modulated signal.

The spin oscillator device 10 includes oscillation signals O ₁ (t), O ₂ (t), ..., having different phases. A plurality of spin oscillators 12, 13, 14 for outputting O _M (t)). The spin oscillator device 10 outputs oscillation signals O ₁ (t), O ₂ (t),..., O _M (t) having the same frequency and discrete phase distribution.

As shown in FIG. 6, the spin oscillator device 10 includes an RF power source 11, a plurality of spin oscillators 12, 13, and 14, and a plurality of delay blocks 15 and 16.

The RF power supply 11 outputs an RF signal having a frequency of f _M. The RF power supply 11 outputs a signal having a frequency equal to or twice the frequency of the oscillation signal output from each spin oscillator.

The plurality of delay blocks 15 and 16 may be implemented by a plurality of capacitors, and may also be implemented by a phase shifter or a phase delay device. The plurality of delay blocks 15 and 16 are connected between the RF power source 11 and each spin oscillator. The plurality of oscillation signals O ₁ (t), O ₂ (t), .., and O _M (t) output from the spin oscillators 12, 13, and 14 may have an evenly distributed phase. The delay blocks 15 and 16 may be implemented with the same delay element.

The first spin oscillator 12 receives the RF signal as an input signal without a delay block and outputs a first oscillation signal O ₁ (t). The second spin oscillator 13 receives a signal having a phase of 2π / M rad delayed by the first delay block 15 as an input signal and outputs a second oscillation signal O ₂ (t).

Each spin oscillator receives a DC current or a DC voltage from a constant current supply circuit (not shown) that supplies a DC current or a DC voltage, and outputs an oscillation signal having an fc frequency.

When a signal of fundamental wave fc or 2fc frequency from the RF power source 11 is injected into each spin oscillator, each spin oscillator is in phase with the injected RF signal and the oscillation signal with improved Q value. Outputs If the frequency of the RF signal coincides with the precession frequency of the spin oscillator, it uses the principle that the Q value increases due to resonance.

The plurality of spin oscillators 12, 13, and 14 are injection-locked with the RF signal from the RF power supply 11 so that the RF signal and the frequency are the same (or the frequency is 1/2 of the RF signal). Output oscillation signals O ₁ (t), O ₂ (t), .., O _M (t) having constant phase differences distributed discretely. The spin oscillator device 10 outputs oscillation signals O ₁ (t), O ₂ (t),..., O _M (t) having the same frequency but having discrete phase distribution.

For example, if the spin oscillators are configured in eight, eight oscillation signals (phases of 0, π / 4, π / 2, 3π / 4, π, 5π /, respectively) in which the phase difference of each signal is π / 4. 4, 3π / 2, 7π / 4 rad, and the frequency is fc).

The oscillating signals O ₁ (t), O ₂ (t),..., O _M (t) having various phases have an fc frequency and are different from each other. In M-PSK modulation, the first oscillation signal O ₁ (t), the second oscillation signal O ₂ (t), and the Mth oscillation signal O _M (t) are represented by Equations 3 to 5 and same.

When the modulator is implemented using the spin oscillator device according to the present invention, oscillation signals (O ₁ (t), O ₂ (t), .., O _M (t)) having a stable frequency and phase are generated. RF signals are injected by injection locking using a plurality of spin oscillators rather than spin oscillators, and oscillation signals O ₁ (t), O ₂ (t), .., O _{M in} each spin oscillation period (t)) outputs stable oscillation signals (O ₁ (t), O ₂ (t), .., O _M (t)) with phase and frequency unstable by connecting with a delay block to have an evenly spaced phase difference. Since the change in frequency is small (or fixed frequency), the Q value is improved. Frequency variation may occur in one spin oscillator, but the frequency variation is greatly reduced and the Q value is improved by the plurality of spin oscillators.

The prior art modulators are complex and bulky to generate an oscillation signal having a fixed frequency and phase, but the present invention provides oscillation signals O ₁ (t) having discretely distributed phases by a spin oscillator device. , O ₂ (t), .., O _M (t)), and select one of the oscillation signals corresponding to the data and output it as a phase-modulated signal, greatly reducing volume and reducing power consumption. Can be.

For example, when the 8-PSK modulator is implemented according to the present invention, the number of oscillators constituting the spin oscillator device is eight. The first oscillation signal O ₁ (t), the second oscillation signal O ₂ (t), and the eighth oscillation signal O ₈ (t), which are outputs of the spin oscillator device, are represented by Equations 6 to 8. .

Data input to the oscillator selector 1 is 000 to 111. If the data is 000, the first oscillation signal O ₁ (t) (Equation 6) having a phase of 0 is selected from the spin oscillator device 10 and output as a modulation signal M-PSK, and if the data is 001, The eighth oscillation signal O8 (t) (Equation 8) having a phase of 7π / 4 rad is selected from the spin oscillator device 10 and output as a modulation signal M-PSK. The second oscillation signal O ₂ (t) (Equation 7) having a phase of π / 4 rad is selected from the spin oscillator device 10 and output as a modulation signal M-PSK. Even if the number of bits (log ₂ M) of the data is increased, the number of spin oscillators is increased to M, and the oscillation signal is selected and outputted according to the data to accurately output the phase-modulated signal (M-PSK) compared to the conventional complex phase modulator. While reducing the volume of the modulator.

The spin oscillator may be implemented with a spin nano pillar structure as illustrated in FIG. 10, and may include a free magnetic layer 21B and a nonmagnetic layer 21C between the first conductor 21A and the second conductor 21E. And a stack structure of the pinned magnetic layer 21D. The free magnetic layer 21B is made of a soft magnetic material in which the spin direction of electrons is easily affected by a magnetic field applied from the outside and the nonmagnetic layer 21C is made of a nonmagnetic metal or an insulating material, The magnetic layer 21D has a fixed magnetism which is not easily influenced by the surrounding magnetic field, and the spin direction of the electrons is hardly affected. The spin oscillator has a tunneling magnetoresistance (TMR) structure when the nonmagnetic layer 21C is formed of an insulating layer, and a GMT (giant manetoresistance) structure when the nonmagnetic layer 21C is a conductive layer. The free magnetic layer 21B may include a magnetic domain wall or a magnetic vortex. The spin oscillator used in the present invention is not limited to FIG. 10 and may be implemented by spin oscillators for outputting an oscillation signal whose frequency varies depending on a current or a voltage.

The constellation point shown in FIG. 7 is an example of an 8-PSK modulation scheme and illustrates a phase of a modulation signal corresponding to data. Data 000 corresponds to a point where the phase is 0 rad, data 001 corresponds to a point where the phase is 7π / 4 rad, and data 010 corresponds to a point that is π / 4 rad.

5 is an M-PSK demodulator using a plurality of spin oscillators according to the present invention, which includes a spin oscillator device 10, a phase selector 8, and a determination unit 7. FIG.

The spin oscillator device 10 includes a plurality of spin oscillators for outputting oscillation signals having different phases. The detailed configuration of the spin oscillator device 10 is as shown in FIG. 6, and has the same function and configuration as the spin oscillator device 10 used in the modulator.

The phase selector 8 compares a phase of a modulated signal x (t) and the plurality of oscillation signals O ₁ (t), O ₂ (t),..., O _M (t) The phase value of the oscillation signal having a phase closest to the modulation signal x (t) is output. The phase selector 8 comprises a mixer block 9, a low pass filter 5 and a selector 6.

The mixer block 9 separately multiplies the modulated signal x (t) and the plurality of oscillation signals O ₁ (t), O ₂ (t), .., O _M (t). The mixed signals x ₁ (t), x ₂ (t), ..., x _M (t) are outputted. The mixer block 9 comprises a first mixer 2 to an Mth mixer 4. The first mixer 2 outputs a first mixed signal x ₁ (t) by multiplying the modulated signal x (t) received from the antenna by the first oscillation signal O ₁ (t). The second mixer 3 outputs a second mixed signal x ₂ (t) by multiplying the modulated signal x (t) received from the antenna by the second oscillation signal O ₂ (t). The M-th mixer 4 multiplies the modulated signal x (t) received from the antenna by the M-th oscillation signal O _M (t) to output the M-th mixing signal x _M (t).

The output (x _i (t)) of the i-th mixer 1 ≦ i ≦ M is expressed by Equations 9 through 12.

The low pass filter 5 filters the plurality of mixing signals x ₁ (t), x ₂ (t),..., X _M (t) which are outputs of the mixer blocks 2, 3, 4. The low pass filtering outputs a plurality of cosine signals x _1L (t), x _2L (t), ..., x _ML (t). When the gain of the low pass filter 5 is 2, the i-th cosine signal x _iL (t) is expressed by Equation 13.

The selector 6 outputs a maximum value of the plurality of cosine signals. The selector 6 selects the i th cosine signal having the largest value among the cosine signals x _iL (t) and outputs phase information θ _c (t _k ) of the cosine signal. That is, a cosine signal having a phase most similar to a phase included in the modulated signal x (t) is selected and outputs θ _c (t _k ) at a time t _k from the selected phase.

The determination unit 7 demodulates data from the phase value θ _c (t _k ) through a decision line which is variably adjusted according to the operating environment. Referring to FIG. 8, when a phase corresponding to 1 of two points perpendicular to the determination line is the reference phase θ _p (t _k ), the reference phase θ _p (t _k ) is 0 degrees in FIG. 8. to be. The determination unit 7 fixes the determination line when there is no phase offset and frequency offset, generates a cos (θ _c (t _k )-θ _p (t _k )) value and cos 0 or 1, which is a value demodulated from (θ _c (t _k ) −θ _p (t _k )), is output. The determination unit may output a cos (θ _c (t _k )-θ _p (t _k )) value from the phase value through a determination line and configure a demodulation unit at a later stage to restore data from the demodulation unit. If the reference phase θ _p (t _k ) is 0 ° and the phase value θ _c (t _k ) is 180 °, the determination unit 7 outputs −1. The determination unit 7 changes the reference phase θ _p (t _k ) if a phase offset or a frequency offset exists. If there is a phase offset, the determination unit 7 compensates for the phase offset by rotating the determination line clockwise by the phase offset. For example, when a 30 degree phase offset occurs, the said determination part 7 moves a decision line 30 degrees clockwise. If the phase offset is 0 °, the decision line is a line that is 90 ° and -90 °. If the phase offset is 30 °, the decision line is rotated and moved to a line that is 120 ° and -60 °. The demodulation signal compensating for the phase offset can be obtained by rotating the judgment line clockwise or counterclockwise by an angle corresponding to the phase offset.

If there is a frequency offset, the fixed determination line cannot compensate for the frequency offset, and the determination unit 7 compensates the frequency offset by changing the real-time determination line according to the applied phase value. For example, the decision line rotates in FIG. 8 by the applied phase value θ _c (t _k ) as shown in FIG. 9. If the value of sin (θ _c (t _k )-θ _p (t _k )) is greater than 0, the determination unit 7 rotates the determination line clockwise with respect to the reference phase θ _p (t _k ). . If the sin (θ _c (t _k )-θ _p (t _k )) value is less than 0, the determination unit 7 rotates the determination line counterclockwise with respect to the reference phase (θ _p (t _k )). Move it. Since the phase change is frequency, to compensate for the frequency offset, the phase change is compensated for in real time. If a frequency offset occurs and the reference phase θ _p (t _{k + 1} ) at t _{k + 1} time moves a predetermined angle clockwise, the decision line also moves clockwise by the predetermined angle. And demodulates the data corresponding to a t _{k +} a is the phase in _one hour (θ _c (t _{k + 1)),} the variation determination line (t _{k + 1)} (shown in FIG. 9). The judgment line fluctuates clockwise or counterclockwise according to the phase value input at t _{k +1} time. When there is one decision line, the output of the decision unit 7 has a value of -1 to 1, and when it is restored to data, it is 1 and 0, respectively.

Another embodiment of the determination unit 7 outputs a cosine value cos (θ _c (t _k )-θ _p (t _k )) in which the reference phase is located with respect to the determination line when the phase applied when the BPSK is used. . If it corresponds to the phase of the first hemisphere, a positive value is output, and if it corresponds to the phase of the second hemisphere, a negative value is output. Alternatively, another embodiment of the determination unit 7 outputs 1 when the phase applied when the BPSK corresponds to the phase of the first hemisphere in which the reference phase is located with respect to the determination line, and corresponds to the phase of the second hemisphere. Output 0. The phase offset compensation scheme is the same as that of the embodiment of the determination unit 7. When a 30 ° phase offset occurs, the determination unit 7 demodulates the data by gradually moving the determination line by 30 °. If the phase offset is 0 °, the decision line is a line that is 90 ° and -90 °. If the phase offset is 30 °, the decision line is moved to a line that is 120 ° and -60 °. When the phase value applied to the determination unit 7 is 91 °, for example, a positive value of cos (91 ° -30 °) is output. If the phase offset is 0 °, a negative value of cos (91 ° -0 °) is output. Since the phase offset can be compensated by moving the determination line by an angle corresponding to the phase offset, a more accurate demodulation signal can be obtained.

An M-PSK demodulation method using a plurality of spin oscillators according to the present invention will be described with reference to FIG. 11.

Phase-discrete oscillation signals are generated from the spin oscillator device 10 shown in FIGS. 5 and 6. The mixer block 9 separately multiplies the received modulation signal with the oscillation signals.

The low pass filter 5 low pass filters the multiply signals and the selector applies phase information of the signal selected as the maximum value among the low pass filtered signals to the determination unit 7.

If the phase offset exists, the phase offset may be compensated through the changed determination line by rotating the determination line clockwise by the phase offset angle. Determining than t _k of the line phase reference (θ _p (t _k)) T _k than the phase value of the time is in the clockwise direction, moving the line is determined for the time t _{k +1} in the clockwise direction, and the line is determined based on the phase (θ _p (t _k)) If the phase value of time is in the counterclockwise direction, the judgment line for t _{k +1} time is shifted in the counterclockwise direction.

If only a phase offset exists and there is no frequency offset, the decision line may be fixed after moving by an angle corresponding to the phase offset.

If there is no phase offset, a step of determining whether a frequency offset exists without performing determination line variation due to the phase offset is performed.

If the frequency offset exists, the frequency offset may be compensated by changing the real-time determination line according to the reference phase and the applied phase information.

The determination unit 7 determines restoration data from the phase information on the basis of the determination line. From the phase information, a signal obtained by cosine calculating a difference between the reference phase and the reference line can be generated and output as a demodulation signal of 0 or 1.

The determination unit 7 may be implemented by a decision algorithm. For example, the determination unit 7 may be implemented as an on-line classification algorithm of machine learning, which is a Kalman filter algorithm or an algorithm for determining real-time data values.

8 and 9 demodulate data through one decision line in the case of BPSK, and up to M-PSK (M ≧ 2) when demodulating the number of decision lines. In the case of 4-PSK, since there are four input data, two decision lines are provided. Since the eight-PSK has eight input data, four determination lines are provided. That is, the M-PSK is provided with M / 2 decision lines, and can demodulate data from a phase applied based on a plurality of decision lines.

Conventionally, the complexity of the modulator is increased by using an oscillator having a good Q value or by adding a phase-locked loop to generate a signal having a fixed frequency and phase, but the present invention provides an M-PSK of equivalent performance without using a separate circuit. Modulators and demodulators can be implemented.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention as defined in the appended claims. You will understand.

1: oscillator selector 2: first mixer
3: mixer 2 4: mixer M
5: low pass filter 6: selector
7: judgment unit 8: phase selector
10: spin oscillator device 11: RF power
12: first spin oscillator 13: second spin oscillator
14: M-th spin oscillator 15: first delay block
16: second delay block 32: I channel level converter
33: Inverter 34: Q channel level converter
35: phase shifter 36: first mixer
37: first band pass filter 38: reference oscillator
39: second mixer 40: third mixer
41: second band pass filter 42: third band pass filter
110: first mixer 120: first low pass filter
130: second mixer 140: loop filter
150: VCO 160: third mixer
170: second low pass filter

Claims (17)

A spin oscillator device comprising a plurality of spin oscillators for outputting oscillating signals having a phase distribution;
A phase selector for comparing phases of the plurality of oscillation signals with a received modulation signal to output phase information of an oscillation signal having a phase closest to the modulation signal; And
And a determination unit for determining reconstruction data from the phase information on the basis of at least one determination line which is variably adjusted according to an operating environment. The method of claim 1,
The determining unit moves the determination line for t _{k + 1} time in a clockwise direction when the phase value of t _k time is in a clockwise direction than the reference phase θ _p (t _k ) of the determination line as the phase offset exists. The plurality of spins, characterized in that for moving the determination line for the t _{k + 1} time counterclockwise if the phase value of the t _k time is counterclockwise than the reference phase (θ _p (t _k )) of the determination line M-PSK demodulator using an oscillator. The method of claim 1,
The determination unit updates the phase information applied from the phase selector in real time to the determination line as the frequency offset exists, and determines the reconstruction data based on the determination line changed in real time. -PSK demodulator. The method of claim 1,
The phase selector,
A mixer block for separately multiplying the modulated signal and the plurality of oscillation signals and outputting a plurality of signals;
A low pass filter for low pass filtering the outputs of the mixer block to output a plurality of cosine signals; And
M-PSK demodulator using a plurality of spin oscillator, characterized in that it comprises a selector for outputting a phase of the cosine signal corresponding to the maximum value of the plurality of cosine signals. The method of claim 1,
The spin oscillator device includes:
An RF power source for outputting an RF signal;
A plurality of delay blocks outputting a signal in which the phase of the RF signal is variously delayed; And
M-PSK demodulator using a plurality of spin oscillators, characterized in that it comprises a plurality of spin oscillators connected to the plurality of delay blocks. In the PSK demodulation method,
Generating oscillation signals having a discrete phase distribution and multiplying the received modulation signal and the oscillation signals separately;
Low pass filtering the multiply signals and applying phase information of a signal selected as a maximum value among the low pass filtered signals to a determination unit; And
And determining restoring data from the phase information on the basis of a decision line. The method according to claim 6,
The step of applying the phase information to the determination unit,
And rotating the decision line clockwise by a phase offset angle to compensate for the phase offset, if there is a phase offset. The method according to claim 6,
The step of applying the phase information to the determination unit,
M-PSK demodulation method using a plurality of spin oscillator, characterized in that the step of compensating the frequency offset by changing the real-time determination line according to the reference phase and the applied phase information, if there is a frequency offset. 8. The method of claim 7,
Compensating the phase offset,
If the phase value of time t _k is in the clockwise direction than the reference phase θ _p (t _k ) of the determination line, the determination line for t _{k + 1} time is shifted clockwise, and the reference phase of the determination line θ _p (t _{and k} )), wherein if the phase value of time t _k is in a counterclockwise direction, the determination line for time t _{k + 1} is moved counterclockwise. The method according to claim 6,
Determining restoration data from the phase information,
And outputting a signal obtained by cosine calculating a difference from a reference phase from the phase information as a demodulation signal as a demodulation signal. A spin oscillator device 10 including a plurality of spin oscillators for outputting oscillation signals having a phase-dispersed distribution;
A plurality of spin oscillators, characterized in that the oscillator selector 1 selects an oscillation signal having a phase corresponding to 1: 1 to the input data from the spin oscillator device 10 and outputs it as a phase modulated signal. M-PSK (M≥2) modulator. 12. The method of claim 11,
The spin oscillator device includes:
An RF power source for outputting an RF signal;
A plurality of delay blocks outputting a signal in which the phase of the RF signal is variously delayed; And
Using a plurality of spin oscillator, characterized in that it comprises a plurality of spin oscillator for receiving the signals delayed in phase than the RF signal output from each delay block as each input signal to output the discrete signals of the phase distribution M-PSK Modulator. 12. The method of claim 11,
The oscillator selector,
M-PSK modulator using a plurality of spin oscillators, characterized in that the decoder, MUX or switching circuit for receiving the binary data as a control signal to select one of the oscillation signals output from the plurality of spin oscillators . The method of claim 12,
The plurality of spin oscillators are M-PSK modulator using a plurality of spin oscillators, characterized in that the output signals from the plurality of delay blocks are injected by an injection locking method to output the phase-tuned oscillation signals . 15. The method of claim 14,
And a constant current supply circuit for supplying a constant current to the plurality of spin oscillators to output oscillation signals of the same frequency or 1/2 frequency with the RF signal. The method of claim 12,
M-PSK modulator using a plurality of spin oscillator, characterized in that the plurality of delay blocks are capacitor array. 17. The M-PSK modulator of any one of claims 11-16 and
The M-PSK modulator using a plurality of spin oscillators, characterized in that the phase-modulated demodulation of the data including the M-PSK demodulator according to any one of claims 1 to 5 for transmitting and receiving the data.

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