KR102459849B1 - Bi-phased on-off keying(ook) transmitter and communication method - Google Patents

Abstract

A data encoder that encodes input data in the form of a transmission sequence, a pulse shaper that generates a pulse based on the time unit of each element of the coded transmission sequence, and randomizes two phases in time units of each element of the encoded transmission sequence a two-phase controller that generates a control signal for switching It is possible to provide an On Off Keying (OOK) transmitter that includes a power amplifier to generate it.

Description

BI-PHASED ON-OFF KEYING (OOK) TRANSMITTER AND COMMUNICATION METHOD

The following embodiments relate to a bi-phased on-off keying transmitter and a communication method.

A wearable device based on a WBAN (Wireless Body Area Network) may be attached to a human body and may wirelessly communicate with a nearby mobile device or a sensor attached to the human body. A transceiver mounted in a wearable device to operate for a long time without a burden on battery recharge may be implemented with low complexity and low power. To this end, it is possible to use a transceiver having a low modulation complexity of a modem along with the use of an ultra-low-power RF structure. An OOK transmitter and receiver capable of data recovery only by envelope detection without phase information of a receiving carrier can be applied to low-power communication of WBAN.

According to an embodiment, an On Off Keying (OOK) transmitter includes: a data encoder for encoding input data in the form of a transmission sequence; a pulse shaper for generating pulses based on bits of the encoded transmission sequence; a bi-phase controller for generating a control signal for randomly switching two phases in time units of each element of the coded transmission sequence; a two-phase switch (bi-phased switch) for randomly switching a phase of a carrier (carrier) generated by a voltage controlled oscillator (VCO) according to the control signal; and a power amplifier (PA) generating a transmission signal using the phase-shifted carrier and the pulse.

The two-phase switch may randomly switch the phase of the carrier in time units of each element of the coded transmission sequence according to the control signal.

The two-phase switch may randomly switch the phase of the carrier by 0 degrees or 180 degrees in time units of each element of the coded transmission sequence.

The data encoder may encode the input data into a pre-determined sequence pattern.

The OOK transmitter may further include a first buffer buffering the carrier generated by the voltage controlled oscillator and transferring the buffer to the two-phase switch.

The OOK transmitter may further include a second buffer for buffering the carrier whose phase is switched in the two-phase switch and transferring the buffer to the power amplifier.

The OOK transmitter may further include a second buffer for buffering the carrier whose phase is switched in the two-phase switch and transferring the buffer to the power amplifier.

According to one embodiment, the OOK transmitter includes a data encoder for encoding input data in the form of a transmission sequence; a pulse shaper for generating a pulse based on the encoded transmission sequence; A two-phase controller that generates a control signal for randomly switching two phases based on a time unit of each element of the coded transmission sequence and a phase of a carrier generated by a voltage controlled oscillator (VCO) according to the control signal and a bi-phasing power amplifier (Bi-phasing PA) that randomly converts , and generates a transmission signal corresponding to the pulse.

The bi-phasing power amplifier may generate the transmission signal by randomly changing the phase of the carrier in units of the period of the encoded transmission sequence according to the control signal.

The bi-phasing power amplifier may generate the transmission signal by randomly changing the phase of the carrier by 0 degrees or 180 degrees in units of a period of the encoded transmission sequence.

The data encoder may encode the input data into a pre-determined sequence pattern.

The OOK transmitter may further include a first buffer buffering the carrier generated by the voltage controlled oscillator and transferring the buffer to the bi-phasing power amplifier.

The OOK transmitter may further include a second buffer for buffering the output of the first buffer.

According to one embodiment, the OOK transmitter includes a buffer for buffering the carrier generated by the voltage controlled oscillator; and a bi-phasing power amplifier that randomly switches the phase of the buffered carrier according to a control signal and generates a transmission signal corresponding to a pulse - the pulse is generated based on a transmission sequence encoding input data. include

The bi-phasing power amplifier may generate a transmission signal corresponding to the pulse by randomly changing the phase of the buffered carrier by 0 degrees or 180 degrees in units of the period of the encoded transmission sequence.

According to an embodiment, a communication method includes: encoding input data in the form of a transmission sequence; generating a pulse based on the encoded transmission sequence; generating a control signal for randomly switching two phases in units of time of each element of the coded transmission sequence; randomly switching a phase of a carrier generated by a voltage-controlled oscillator according to the control signal; and generating a transmission signal using the phase-shifted carrier and the pulse.

Randomly shifting the phase of the carrier may include randomly shifting the phase of the carrier by 0 degrees or 180 degrees in time units of each element of the coded transmission sequence according to the control signal.

The method may further include buffering the generated carriers generated by the voltage controlled oscillator.

According to an embodiment, a communication method includes: encoding input data in the form of a transmission sequence; generating a pulse based on the encoded transmission sequence; generating a control signal for randomly switching two phases based on a time unit of each element of the coded transmission sequence; and randomly changing a phase of a carrier generated by a voltage-controlled oscillator according to the control signal, and generating a transmission signal corresponding to the pulse.

The generating of the transmission signal may include generating the transmission signal by randomly shifting the phase of the carrier by 0 degrees or 180 degrees in units of a period of the coded transmission sequence according to the control signal.

1 is a structural block diagram of an OOK transmitter including a bi-phased switch according to an embodiment.
2 is a diagram illustrating a circuit configuration of a two-phase switch according to an embodiment.
3 is a timing diagram of an OOK transmitter according to an embodiment.
4 is a structural block diagram of an OOK transmitter according to another embodiment.
5 is a structural block diagram of an OOK transmitter including a bi-phasing power amplifier (Bi-phasing PA) according to an embodiment.
6 is a diagram illustrating a circuit of a bi-phasing power amplifier according to an embodiment.
FIG. 7 is a diagram illustrating an active signal path of the bi-phasing power amplifier shown in FIG. 6 .
8 is a circuit in which a bi-phasing power amplifier according to an embodiment is implemented in another form.
9 is a diagram illustrating an active signal path of the bi-phasing power amplifier shown in FIG. 8 .
10 is a diagram illustrating a simulation result for a phase change of a bi-phasing power amplifier according to an exemplary embodiment.
11 is a structural block diagram of an OOK transmitter including a bi-phasing power amplifier according to another embodiment.
12 is a structural block diagram of an OOK transmitter including a frequency error compensation circuit according to an embodiment.
13 is a schematic diagram of a coarse tuing circuit for frequency error compensation according to an embodiment.
14 is an operation timing diagram of the course tuning circuit shown in FIG. 13 .
15 is a graph illustrating a spectrum comparison result before and after switching a phase of a carrier in an OOK transmitter according to an embodiment.
16 is a structural block diagram of an OOK receiver according to an embodiment.
17 is a flowchart illustrating a communication method according to an embodiment.
18 is a flowchart illustrating a communication method according to another embodiment.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Like reference numerals in each figure indicate like elements.

Various modifications may be made to the embodiments described below. It should be understood that the embodiments described below are not intended to limit the embodiments, and include all modifications, equivalents, and substitutions thereto.

Terms used in the examples are only used to describe specific examples, and are not intended to limit the examples. The singular expression includes the plural expression unless the context clearly dictates otherwise. In this specification, terms such as "comprises" or "have" are intended to designate that the features, numbers, steps, operations, components, parts, or combinations thereof described in the specification exist, but one or more other features It is to be understood that it does not preclude the possibility of the presence or addition of numbers, steps, operations, components, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the embodiment belongs. Terms such as those defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. does not

In addition, in the description with reference to the accompanying drawings, the same components are assigned the same reference numerals regardless of the reference numerals, and the overlapping description thereof will be omitted. In the description of the embodiment, if it is determined that a detailed description of a related known technology may unnecessarily obscure the gist of the embodiment, the detailed description thereof will be omitted.

1 is a structural block diagram of an OOK transmitter including a bi-phased switch according to an embodiment.

Referring to FIG. 1A , the OOK transmitter 100 according to an embodiment includes a voltage controlled oscillator (VCO) 110 , a bi-phased switch 130 , and a power amplifier. a (Power Amplifier; PA) 150 , a Data Encoder 160 , a Bi-phase controller 170 , and a Pulse Shaper 180 . The voltage controlled oscillator 110 may generate carriers. In other words, the voltage-controlled oscillator 110 may output an RF oscillation signal corresponding to the carrier frequency.

The carrier generated by the voltage-controlled oscillator 110 may be OOK-modulated in the power amplifier 150 by a data-encoded signal transmitted from the data encoder 160 through the pulse shaper 180 .

The two-phase switch 130 randomly switches the phase of the carrier generated by the voltage-controlled oscillator 110 according to the control signal generated by the two-phase controller 170 . The two-phase switch 130 may randomly switch the phase of the carrier in units of time of each element of the coded transmission sequence according to the control signal. Here, the 'time unit of each element of the coded transmission sequence' is, for example, each of the coded transmission sequence 320 {0, 1, 1, 0} corresponding to the data 310 '0' in FIG. 3 . It can be understood as the time required to transmit the element 0 or 1. The circuit structure of the two-phase switch 130 will be described with reference to FIG. 2 .

The two-phase switch 130 may randomly switch the phase of the carrier by, for example, 0 degrees or 180 degrees in time units of each element of the coded transmission sequence, for suppression of the line spectrum. A result in which the phase of the carrier output from the voltage controlled oscillator 110 is randomly switched by 0 degrees or 180 degrees through the two-phase switch 130 can be seen through the timing diagram of FIG. 3 . According to one embodiment, the two-phase switch 130 may be located between the voltage controlled oscillator 110 and the power amplifier 150 . The OOK transmitter 100 may perform bi-phasing such that the carrier has two phases of 0 degrees and 180 degrees by randomly switching the phase of the carrier by the two-phase switch 130 . In this case, the two-phase switch 130 may randomly take any one of two values of 0 degrees and 180 degrees as the phase of the carrier according to the control signal generated by the two-phase controller 170 .

A power amplifier (PA) 150 is a phase-shifted carrier (eg, see 360 in FIG. 3 ) via a two-phase switch 130 and a pulse generated from a pulse shaper 180 (eg, FIG. 3 ) 3) is used to generate a transmission signal (eg, refer to 370 of FIG. 3). The power amplifier 150 may perform OOK modulation of the carrier by individually controlling the power of each of the 15 unit cells to be on or off according to a signal from the pulse shaper 180 .

The data encoder 160 encodes an input data sequence into a transmission sequence by using a transformation scheme previously given in the system. The data encoder 160 may encode, for example, a data sequence provided from a digital baseband into a pre-determined sequence pattern composed of digital values. . For example, the data encoder 160 may encode the transmission sequence corresponding to the input data sequence 1 as 1 as it is, and may encode the transmission sequence corresponding to the input data sequence 0 as 0 as it is. In addition, the data encoder 160 encodes the transmission sequence corresponding to the input data sequence 1 as [1,0,0,1] and converts the transmission sequence corresponding to the input data sequence 0 to [0,1,1,0]. can be encoded as In addition, the data encoder 160 may configure a plurality of specific M elements of the input data sequence and then map different transmission sequences including a plurality of specific L elements to different input data sequences. .

In the above embodiments, the data encoder 160 may use each element of the transmission sequence as an element selected from the set {-1, 0, 1}, which is used for ternary sequence spreading in which the types of each element of the transmission sequence are three. corresponds to

The two-phase controller 170 generates a control signal for randomly switching two phases based on the transmission sequence encoded by the data encoder 160 . Bi-phase shift by the control signal of the two-phase controller 170 may be implemented in synchronization with the output of the data encoder 160 .

The pulse shaper 180 performs input data (eg, FIG. 3 ) based on a transmission sequence encoded by the data encoder 160 (eg, refer to 320 of FIG. 3 ) in order to improve spectral efficiency. A pulse (see, for example, 330 of FIG. 3 ) is generated corresponding to 310 of FIG. In this case, the shape of the pulse generated by the pulse shaper 180 may be the shape of a quantized pulse implemented by a digital pulse shaping filter.

Referring to FIG. 1B , the OOK transmitter 100 according to an embodiment includes a voltage controlled oscillator (VCO) 110 , a first buffer 120 , and a bi-phased switch 130 . , a power amplifier 150 , a data encoder 160 , a two-phase controller 170 , and a pulse shaper 180 . The first buffer 120 may be positioned between a voltage controlled oscillator (VCO) 110 and a bi-phased switch 130 . The first buffer 120 may buffer the carriers generated by the voltage controlled oscillator 110 and transfer the buffered carriers to the two-phase switch 130 . Here, "buffering the carrier" means that the frequency of the voltage controlled oscillator 110 prevents frequency fluctuations with respect to the control of the two-phase controller 170 .

In the embodiment of FIG. 1 ( b ), voltage is controlled by the bi-phasing operation of the two-phase switch 130 by adding the first buffer 120 between the voltage controlled oscillator 110 and the two-phase switch 130 . It is possible to minimize phase noise degradation occurring in the oscillator 110 .

The first buffer 120 minimizes the impedance change appearing at the output of the voltage controlled oscillator 110 by the two-phase switch 130 and the power amplifier 150, thereby reducing the voltage controlled oscillator 110 due to the bi-phasing operation. It is possible to minimize the phase noise degradation that occurs.

Referring to FIG. 1C , the OOK transmitter 100 according to an embodiment includes a voltage controlled oscillator (VCO) 110 , a bi-phased switch 130 , and a second buffer 140 . , a power amplifier 150 , a data encoder 160 , a two-phase controller 170 , and a pulse shaper 180 .

The second buffer 140 may be located between the bi-phased switch 130 and the power amplifier 150 . The second buffer 140 may buffer the carrier whose phase is switched in the two-phase switch 130 and transmit it to the power amplifier 150 . In one embodiment, by adding the second buffer 140 in front of the power amplifier 150, phase noise ( phase noise) can be minimized.

The second buffer 140 shakes the load impedance of the voltage-controlled oscillator 110 due to the pulse-shaping operation of the power amplifier 150 , thereby affecting the phase noise generated on the carrier of the pre-arm controlled oscillator 110 . can be minimized.

Referring to FIG. 1 ( d ), the OOK transmitter 100 according to an embodiment includes a voltage controlled oscillator (VCO) 110 , a first buffer 120 , and a bi-phased switch 130 . , a second buffer 140 , a power amplifier 150 , a data encoder 160 , a two-phase controller 170 , and a pulse shaper 180 .

The use of the first buffer 120 and the second buffer 10 described with reference to FIG. 1 may be excluded as in 1(a) for power saving or other reasons, and 1(b) or It can be used individually as in 1(c), or together as in 1(d).

In one embodiment, by randomly changing the phase of the carrier in accordance with the synchronization of the chip rate, the harmonic spur appearing at the chip rate or 1/2 chip rate in the output waveform of the OOK transmitter 100 ) can be removed. The chip rate may be understood as a data rate of a digital sequence corresponding to an output of the data encoder 160 .

2 is a diagram illustrating a circuit configuration of a two-phase switch according to an embodiment. Fig. 2(a) shows a symbol of a two-phase switch and Fig. 2(b) shows a detailed circuit for symbol (a).

A circuit of a two-phase switch according to an embodiment may include a total of four transmission gates 210 , 220 , 230 , and 240 . Of the four transmission gates 210, 220, 230, 240, two transmission gates 210 and 240 are used as a signal path for inphase of 0 degree, and the remaining two transmission gates 220 and 230 are 180 degrees. It can be used as a signal path for phase shift of the figure. In this case, the two transmission gates 220 and 230 used as a signal path for phase shift of 180 degrees may have a + terminal and a - terminal of the signal path cross connected to each other for phase shift.

3 is a timing diagram of an OOK transmitter according to an embodiment.

Referring to FIG. 3 , input data 310 , a transmission sequence encoded by a data encoder 320 , a pulse shaping code 330 generated by a pulse shaper, 2- Bi-phased control signal 340 generated by the phase controller, the input 350 of the two-phase switch, the output 360 of the two-phase switch and the OOK TX output of the OOK transmitter ( 370) is shown. Here, the input 350 of the two-phase switch corresponds to the carrier generated by the voltage controlled oscillator (VCO), and the transmit signal (OOK TX output) 370 of the OOK transmitter corresponds to the output of the power amplifier.

One bit of the input data 310 may be encoded into four transmission sequences 320 having a value of, for example, '0' or '1' by Data Encore. In the input data 310 , '0' may be encoded as the transmission sequences 320 '0110', and the data 310 '1' may be encoded as the transmission sequences 320 '1001'. This shows an example in which the data encoder encodes OOK4 with a spreading factor of 4, but it may be encoded using other encoding methods.

The pulse 330 generated by the pulse shaper is a pulse generated so that the pulse shaper corresponds to the input data 310 based on the transmission sequence 320 encoded by the data encoder in order to improve spectral efficiency. . In this case, the shape of the pulse 330 may be that of a quantized pulse.

The control signal 340 may switch the two phase states of '1' and '-1' in a random order at the same period as the encoded transmission sequence 320 . Here, '+1' may mean 0 degree phase conversion (Inphase), and '-1' may mean 180 degree phase conversion (Out of phase).

The input 350 of the two-phase switch, that is, the carrier generated in the voltage controlled oscillator (VCO) in the case of FIG. 1 passes through the two-phase switch to have two phases of 0 degrees and 180 degrees. Phasing) can be done. In this case, the output 360 of the two-phase switch may randomly take any one of two values of 0 degrees and 180 degrees as the phase of the carrier according to the control signal generated by the two-phase controller.

The output 360 of the two-phase switch is combined with the pulse 330 generated by the pulse shaper in the power amplifier and output as the OOK TX output 370 of the OOK transmitter. A carrier corresponding to the input 350 of the two-phase switch may be modulated into a Gaussian pulse-shaped code like the transmission signal 370 according to the control signal 340 . In one embodiment, a Gaussian pulse shape is assumed, but like the encoding method, a pulse code other than Gaussian may be used. Portions indicated by dotted lines in FIG. 3 indicate portions in which the phase is changed, and one example in which the phase is changed from 0 degrees to 180 degrees is indicated by 301 and 303 .

4 is a structural block diagram of an OOK transmitter according to another embodiment.

Referring to FIG. 4 , the OOK transmitter 400 according to an embodiment includes a Voltage Controlled Oscillator (VCO) 410 , a Buffer 420 , and a Power Amplifier (PA) 430 . , a data encoder 440 , a bi-phase controller 450 , a pulse shaper 460 , and a matching block 470 .

The voltage controlled oscillator 410 generates a carrier. In other words, the voltage controlled oscillator 410 may output a radio frequency (RF) oscillation signal corresponding to the carrier frequency.

The buffer 420 may buffer carriers generated by the voltage controlled oscillator 110 .

The power amplifier 430 may generate a transmission signal using the control signal generated by the two-phase controller 450 and the pulse generated by the pulse shaper 460 .

In an embodiment, the carrier generated in the voltage controlled oscillator 410 may pass through the buffer 420 and then be connected to the power amplifier 430 and transmitted to the OOK receiver through the antenna. At this time, the power amplifier 430 may perform OOK modulation (On-Off keying modulation) of the carrier by controlling the power to be on or off. The power amplifier 430 may be configured of a plurality of (N) digital power amplifiers composed of, for example, a thermometer code (or a binary code) for pulse shaping. . When a carrier is turned on by using a plurality of digital power amplifiers, the amplitude of the power amplifier 430 may have N states. For example, in the case of binary code, the amplitude of the power amplifier 430 may have 2^N states.

The data encoder 440 encodes an input data sequence into a transmission sequence using a previously given transformation method. The data encoder 440 may encode, for example, a data sequence provided from a digital baseband into a preset sequence pattern composed of digital values. In one embodiment, the data encoder 440 converts the M times oversampled pulse shaping code value to N thermometer codes in comparison to the encoded transmission sequence to power the N digital power amplifiers. can be individually controlled on or off. The N digital power amplifiers may be power amplifiers composed of N binary codes.

The two-phase controller 450 generates a control signal for randomly switching the phase of the carrier into two phases of 0 degrees and 180 degrees based on the coded transmission sequence. The generated control signal can suppress harmonic line spur appearing in the OOK transmitter by randomly switching the phase of the carrier in time units of each element of the transmission sequence encoded by the data encoder 440. .

The pulse shaper 460 generates a pulse corresponding to the input data based on the transmission sequence encoded by the data encoder 440 . The transmission sequence encoded by the data encoder 440 may be oversampled by, for example, a digital filter included in the pulse shaper 460 and converted into a pulse shaping code.

The matching block 470 matches the impedance so that the output power of the power amplifier 430 is transmitted to the antenna with minimal loss.

In an embodiment, the periodicity of the power spectrum of the baseband symbol by randomly switching the phase of the carrier in the RF domain by 0 degrees and 180 degrees in the unit of the period of the coded transmission sequence (eg, symbol) , for example, a line spectrum phenomenon may be removed.

5 is a structural block diagram of an OOK transmitter including a bi-phasing power amplifier (Bi-phasing PA) according to an embodiment.

Referring to FIG. 5 , the OOK transmitter 500 according to an embodiment includes a voltage controlled oscillator (VCO) 410 , a buffer 420 , a bi-phasing power amplifier (Bi-phasing PA) 530 , and a data encoder 440 . ), a two-phase controller 450 , and a pulse shaper 460 .

The bi-phasing power amplifier 530 generates a transmission signal corresponding to a pulse by randomly changing a phase of a carrier generated by the voltage-controlled oscillator 410 according to a control signal. The bi-phasing power amplifier 530 may generate a transmission signal by randomly converting the phase of the carrier in units of time of each element of the coded transmission sequence according to the control signal.

The bi-phasing power amplifier 530 may generate a transmission signal by randomly switching the phase of the carrier, for example, by 0 degrees or 180 degrees in time units of each element of the coded transmission sequence, in order to suppress the line spectrum. .

The bi-phasing power amplifier 530 may generate a transmission signal by performing OOK modulation of the carrier by controlling the power to be on or off. A circuit configuration of the bi-phasing power amplifier 530 according to an embodiment is as shown in FIG. 6 or FIG. 9 .

Configurations except for the bi-phasing power amplifier 530 are the same as those of the embodiment of FIG. 4 , and thus a description thereof will be omitted.

6 is a diagram illustrating a circuit of a bi-phasing power amplifier according to an embodiment.

6, a symbol (a) and a detailed circuit (b) of an X-coupled bi-phasing power amplifier according to an embodiment are shown.

A bi-phasing power amplifier according to an embodiment is a power amplifier having a function of converting a phase of an output carrier by 0 degrees and 180 degrees according to an externally applied control signal (eg, a control signal of a two-phase controller).

In FIG. 6B , the control signal may be generated by the two-phase controller and applied to the bi-phasing power amplifier (Unit_PA[15:1]) at an encoding data rate of 1 MHz. In this case, the control signal may be applied to the gate terminals of M1, M2, M3, and M4, which are switching transistors (Switching TR) connected to the common source type constituting the bi-phasing power amplifier. The control signal may be, for example, a phase shifting (PS) signal (Our-of-phase, In-phase) that is a switch control signal of 1 and 0.

For example, when the control signal is '1', the transistors M1[15:1] and M4[15:1] may be turned on as a gain path of the signal. When the control signal is '0', the transistors M5 and M8 may be turned on as a gain path of the signal. An active signal path of the bi-phasing power amplifier according to the control signal is shown in FIG. 7 .

The thermometer code TMPA[15:1] for Gaussian pulse shaping is to be applied to each gate of the transistors M10 and M11 of the Cascode Amp of the Unit_PA[15:1]. can

The TMPA signal may be applied to the bi-phasing power amplifier at a sampling rate of 6 MHz corresponding to 6 times the encoded transmission sequence, for example, an encoding symbol. In this case, for one Gaussian pulse, for example, a total of 7 sampling data, eg, 1, 4, 9, 11, 9, 4, 1, may be applied.

FIG. 7 is a diagram illustrating an active signal path of the bi-phasing power amplifier shown in FIG. 6 .

Referring to FIG. 7 , an active signal path (a) when the inphase signal is '1' and an active signal path (b) when the inphase signal is '0' are shown. When the inphase signal is '1', the phase of the input signal and the phase of the output signal are the same, and when the inphase signal is '0', the phase of the input signal and the phase of the output signal may be inverted by 180 degrees.

8 is a circuit in which a bi-phasing power amplifier according to an embodiment is implemented in another form. In the above example, (a) shows a bi-phasing power amplifier circuit implemented in another form, and (b) shows a detailed circuit for Unit_PA[N:1].

9 is a diagram illustrating an active signal path of the bi-phasing power amplifier shown in FIG. 8 . In FIG. 9, when the inphase signal is '1', the phase of the input signal and the phase of the output signal are the same, and when the inphase signal is '0', the phase of the input signal and the phase of the output signal can be inverted by 180 degrees have.

10 is a diagram illustrating a simulation result for a phase change of a bi-phasing power amplifier according to an exemplary embodiment.

Referring to FIG. 10 , a simulation result in which the phase of the bi-phasing power amplifier is changed by 180 degrees according to a control signal is shown. When the inphase signal is changed from '1' to '0' and from '0' to '1', it can be seen that the phase of the carrier input to the bi-phasing power amplifier is inverted by 180 degrees and output.

11 is a structural block diagram of an OOK transmitter including a bi-phasing power amplifier (Bi-phasing PA) according to another embodiment.

Referring to FIG. 11 , the OOK transmitter 1100 according to an embodiment includes a voltage controlled oscillator 410 , a third buffer 1120 , a fourth buffer 1130 , a bi-phasing power amplifier 530 , and a data encoder 440 . ), a two-phase controller 450 , and a pulse shaper 460 .

The third buffer 1120 may buffer the carrier generated by the voltage controlled oscillator 410 and transmit it to the fourth buffer 1120 .

The fourth buffer 1130 may buffer the output of the third buffer 1120 and transmit it to the bi-phasing power amplifier 530 . In an embodiment, load pulling of the voltage controlled oscillator (VCO) 410 due to the bi-phasing power amplifier 1140 can be minimized by the second buffer 1130 .

Configurations except for the third buffer 1120 and the fourth buffer 1130 are the same as in the embodiments of FIGS. 4 and 5 , and thus descriptions thereof will be omitted.

According to an embodiment, an OOK transmitter including only a voltage controlled oscillator (VCO) 410 , a third buffer 1120 , and a bi-phasing power amplifier 530 among the components shown in FIG. 11 may be considered. In this case, the third buffer 1120 buffers the carriers generated by the voltage-controlled oscillator 410 , and the bi-phasing power amplifier 530 randomizes the phase of the carriers buffered in the third buffer 1120 according to the control signal. to generate a transmission signal corresponding to the pulse. In this case, the pulse may be generated based on a transmission sequence in which input data is encoded. The bi-phasing power amplifier 530 may generate a transmission signal corresponding to a pulse by randomly converting the phase of the buffered carrier by 0 degrees or 180 degrees in time units of each element of the coded transmission sequence.

12 is a structural block diagram of an OOK transmitter including a frequency error compensation circuit according to an embodiment.

12 , the OOK transmitter according to an embodiment includes a crystal oscillator (XO) 1205 , a coarse tuning unit (CT) 1210 , a voltage controlled oscillator (VCO) 1215 , a buffer 1220 , and a power amplifier. 1230 , a matching block 1240 , a data encoder 1250 , a two-phase controller 1260 , and a pulse shaper 1270 .

Here, the operation of the voltage controlled oscillator 1215 , the buffer 1220 , the power amplifier 1230 , the matching block 1240 , the data encoder 1250 , the two-phase controller 1260 , and the pulse shaper 1270 is shown in FIG. 1, the operation of the voltage controlled oscillator 110, the buffer 120, the power amplifier 130, the data encoder 140, the two-phase controller 150, the pulse shaper 160, and the matching block 170, and Since they are the same, the description of the corresponding part will be referred to.

A crystal oscillator (XO) 1205 generates a reference frequency.

The coarse tuning unit (CT) 1210 may coarsely tune the oscillation frequency of the voltage controlled oscillator 1315 . A course tuning method of the course tuning unit (CT) 1210 will be described with reference to FIG. 13 . A portion indicated by a dotted line in FIG. 12 may constitute a coarse tuning circuit described in FIG. 13 .

Since the OOK receiver according to an embodiment uses OOK modulation, envelope detection is performed when demodulating data. Therefore, accurate phase information of the carrier is not required, and the sensitivity of the receiver is also low compared to the sensitivity of the transmitter for frequency accuracy.

The OOK transmitter and receiver according to an embodiment use the above-described characteristics to continuously drive a phase locked loop (PLL) with a large relative power consumption, instead of continuously driving a phase locked loop (PLL) with a large relative power consumption, it is driven in a course tuning method according to the on/off cycle. can In this case, the phase locked loop may control the frequencies of the transmit and receive carriers according to the on/off cycle.

In one embodiment, coarse tuning may be used for frequency tuning of multiple channels.

The coarse tuning unit (CT) 1210 may track the frequency using a 15-bit capacitor bank (not shown) having fine resolution. The 15-bit capacitor bank is a component of the voltage controlled oscillator 1215 . In one embodiment, even if the coarse tuning unit (CT) 1210 is deactivated after the target channel frequency is locked by using the capacitor bank, frequency drift may not occur much.

In addition, in one embodiment, the frequency tuning is performed using the coarse tuning unit (CT) 1210 before the transmission of the transmission signal starts, and the power of the coarse tuning unit (CT) 1210 is turned on while the transmission signal is transmitted. The frequency may be synthesized according to a periodic duty cycle that is turned off. By synthesizing frequencies according to the periodic duty cycle as described above, power consumption due to frequency synthesizing in the phase-locked loop can be minimized.

13 is a schematic diagram of a coarse tuing circuit for frequency error compensation according to an embodiment.

Referring to FIG. 13 , a functional block of the course tuning unit 1330 operating according to a periodic duty cycle is illustrated.

When the course tuning unit 1330 receives channel information CH_SEL<4:0>, the mapping table 1335 converts the channel information to a corresponding reference channel code CH_REF<17: Convert to 0>.

The oscillation frequency generated by the voltage controlled oscillator 1350 may be divided by 2 by a divider 1331 and input to the 18-bit counter 1332 . The output VCO_CNT<17:0> of the counter 1332 may be compared with the reference channel code CH_REF<17:0> in the coarse tuning control unit (CT Controller) 1333 .

Thereafter, the course tuning control unit 1333 is the tuning control unit (Tuning Controller) 1334 based on the comparison between the output of the counter 1332 and the reference channel code and continuous SAR (Successive Approximation Register) logic Up or down (Down) signal can be transmitted.

Coarse Cap[9:0] and Fine Cap[4:0] of the voltage controlled oscillator 1350 may be adjusted and fixed according to the target frequency through such a frequency tracking loop. In this case, the accuracy and the fixed time of the tracking loop may be traded off according to an activation time of the 18-bit counter 1332 . The 18-bit counter 1332 may be set by EN_CNT = '1'.

Course tuning performed in an embodiment may be performed in two steps: coarse tracking having an active time of 120xREF_CLK and fine tracking having an active time of 1000xREF_CLK.

The MUX 1337 selects the coarse tracking control signal C_R<12:0> and the fine tracking control signal F_R<12:0> according to the C/F_MODE signal and transmits it to the reference divider 1336. can

After the frequency calculation is completed, in the course tuning unit 1330 , power of almost all blocks except for the tuning controller 1334 may be turned off. Each of the blocks 1331 , 1332 , 1333 , 1335 , 1336 , and 1337 indicated by dotted lines in FIG. 13 indicates that power is turned off after the frequency operation is completed.

14 is an operation timing diagram of the course tuning circuit shown in FIG. 13 . 14 , the 18-bit counter starts counting when the signal EN_CNT applied to the counter is high or '1'. When the signal EN_CNT becomes low or '0', the signal EN_COMP applied to the coarse tuning control unit, the signal EN_CTUNE applied to the tuning control unit, and the reset signal RST_CNT applied to the 18-bit counter are sequentially While being activated, comparison in the course tuning controller, updating of capacitor bank values, and resetting of counters may be performed. Each of the signals RST_CNT, EN_CNT, EN_COMP, and EN_CTUNE may be obtained by dividing the reference clock generated by the crystal oscillator by a reference divider.

15 is a graph illustrating a spectrum comparison result before (a) and after (b) changing a phase of a carrier in an OOK transmitter according to an embodiment.

Referring to FIG. 15 , as a result of randomly changing the phase of a carrier at a rate of 1 M chip/sec, it can be seen that line spurs appearing at intervals of 1 MHz disappear.

In one embodiment, by bi-phasing the carrier by a two-phase switch or a bi-phasing power amplifier, harmonic spurs present on the transmit spectrum can be removed, and the spectral mask matching of the OOK transmitter and deterioration of the transmit signal quality can also be eliminated. have.

16 is a structural block diagram of an OOK receiver according to an embodiment.

Referring to FIG. 16 , an OOK receiver 1600 according to an embodiment includes an RF/analog block 1610 , an envelope detector 1620 , an analog-digital converter (ADC) 1630 , and a data decoder (Data). Decoder) (1640).

A signal received through the antenna may be amplified through the RF/analog block 1610 , and the amplified modulated carrier may be demodulated into a baseband signal through the envelope detector 1620 .

At this time, since the envelope detector 1620 demodulates a signal by a square operation, bi-phasing inserted to remove line spurs in an embodiment does not affect demodulation. A signal digitized through the ADC 1630 (or a comparator) may be restored into a data sequence through the data decoder 1640 .

As described above, since the OOK receiver 1600 demodulates the signal through envelope detection, the randomized code conversion of the carrier appearing in the period of the coded transmission sequence does not affect the demodulation process.

17 is a flowchart illustrating a communication method according to an embodiment.

Referring to FIG. 17 , the transmitter according to an embodiment encodes input data in the form of a transmission sequence ( 1710 ).

The transmitter generates a pulse corresponding to the input data based on the encoded transmission sequence ( 1720 ).

The transmitter generates a control signal for randomly switching two phases based on the coded transmission sequence (1730).

The transmitter randomly switches the phase of the carrier generated by the voltage-controlled oscillator according to the control signal (1740). The transmitter may randomly switch the phase of the carrier by 0 degrees or 180 degrees in time units of each element of the coded transmission sequence according to the control signal.

The transmitter generates a transmission signal using the phase-shifted carrier in operation 1740 and the pulse generated in operation 1720 (operation 1750).

The transmitter may perform step 1740 after buffering the generated carriers generated by the voltage controlled oscillator. Also, the transmitter may perform step 1750 after buffering the phase-shifted carrier in step 1740 .

18 is a flowchart illustrating a communication method according to another embodiment.

Referring to FIG. 18 , the transmitter according to an embodiment encodes input data into a transmission sequence form ( 1810 ).

The transmitter generates a pulse corresponding to the input data based on the transmitted sequence encoded in step 1810 ( 1820 ).

The transmitter generates a control signal based on the coded transmission sequence in step 1810 ( 1830 ). The control signal is for randomly switching the two phases.

The transmitter randomly switches the phase of the carrier generated by the voltage-controlled oscillator according to the control signal generated in step 1830 to generate a transmission signal corresponding to a pulse (1840). In operation 1840, the transmitter may generate a transmission signal by randomly converting the phase of the carrier by 0 degrees or 180 degrees in time units of each element of the coded transmission sequence according to the control signal.

1 to 15 may be equally applied to the communication method of FIGS. 17 and 18 , and thus a more detailed description thereof will be omitted.

The device described above may be implemented as a hardware component, a software component, and/or a combination of the hardware component and the software component. For example, devices and components described in the embodiments may include, for example, a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable array (FPA), It may be implemented using one or more general purpose or special purpose computers, such as a programmable logic unit (PLU), microprocessor, or any other device capable of executing and responding to instructions. The processing device may execute an operating system (OS) and one or more software applications running on the operating system. The processing device may also access, store, manipulate, process, and generate data in response to execution of the software. For convenience of understanding, although one processing device is sometimes described as being used, one of ordinary skill in the art will recognize that the processing device includes a plurality of processing elements and/or a plurality of types of processing elements. It can be seen that may include For example, the processing device may include a plurality of processors or one processor and one controller. Other processing configurations are also possible, such as parallel processors.

The software may comprise a computer program, code, instructions, or a combination of one or more thereof, which configures a processing device to operate as desired or is independently or collectively processed You can command the device. The software and/or data may be any kind of machine, component, physical device, virtual equipment, computer storage medium or device, to be interpreted by or to provide instructions or data to the processing device. , or may be permanently or temporarily embody in a transmitted signal wave. The software may be distributed over networked computer systems and stored or executed in a distributed manner. Software and data may be stored in one or more computer-readable recording media.

The method according to the embodiment may be implemented in the form of program instructions that can be executed through various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, etc. alone or in combination. The program instructions recorded on the medium may be specially designed and configured for the embodiment, or may be known and available to those skilled in the art of computer software. Examples of the computer-readable recording medium include magnetic media such as hard disks, floppy disks and magnetic tapes, optical media such as CD-ROMs and DVDs, and magnetic such as floppy disks. - includes magneto-optical media, and hardware devices specially configured to store and execute program instructions, such as ROM, RAM, flash memory, and the like. Examples of program instructions include not only machine language codes such as those generated by a compiler, but also high-level language codes that can be executed by a computer using an interpreter or the like. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the embodiments, and vice versa.

Although the embodiments have been described with reference to the limited drawings as described above, various modifications and variations are possible by those skilled in the art from the above description. For example, the described techniques are performed in a different order than the described method, and/or the described components of the system, structure, apparatus, circuit, etc. are combined or combined in a different form than the described method, or other components Or substituted or substituted by equivalents may achieve an appropriate result. Therefore, other implementations, other embodiments, and equivalents to the claims are also within the scope of the following claims.

100: OOK transmitter
110: voltage controlled oscillator (VCO)
120: Buffer
130: Power Amplifier (Power Amplifier)
140: data encoder (Data Encoder)
150: Bi-phase controller
160: Pulse Shaper
170: matching block

Claims (20)

a data encoder that encodes the input data in the form of a transmission sequence;
a pulse shaper for generating pulses based on bits of the encoded transmission sequence;
a bi-phase controller for generating a control signal for randomly switching a phase of a carrier between two phases in units of time of each element of the coded transmission sequence;
a bi-phased switch that randomly switches a phase of the carrier generated by a voltage controlled oscillator (VCO) according to the control signal by a bi-phasing operation;
a power amplifier (PA) for generating a transmission signal using the phase-shifted carrier and the pulse; and
It is located between the voltage controlled oscillator and the two-phase switch, and buffers the carrier generated in the voltage controlled oscillator (VCO) to reduce a change occurring in the voltage controlled oscillator by the bi-phasing operation, - OOK (On Off Keying) transmitter including a first buffer to pass to the phase switch. According to claim 1,
The two-phase switch is
An OOK transmitter that randomly switches the phase of the carrier in time units of each element of the coded transmission sequence according to the control signal. 3. The method of claim 2,
The two-phase switch is
An OOK transmitter that randomly shifts the phase of the carrier by 0 degrees or 180 degrees in time units of each element of the coded transmission sequence. According to claim 1,
The data encoder
An OOK transmitter that encodes the input data into a preset sequence pattern (pre-determined sequence pattern). delete According to claim 1,
A second buffer for buffering the phase-shifted carrier in the two-phase switch and transferring it to the power amplifier
Further comprising, OOK transmitter. delete a data encoder that encodes the input data in the form of a transmission sequence;
a pulse shaper for generating a pulse based on the encoded transmission sequence;
a two-phase controller for generating a control signal for randomly switching a phase of a carrier between two phases based on a time unit of each element of the coded transmission sequence;
A bi-phasing power amplifier (Bi-phasing PA) that randomly switches the phase of the carrier generated by a voltage controlled oscillator (VCO) according to the control signal by a bi-phasing operation and generates a transmission signal corresponding to the pulse ; and
It is located between the voltage-controlled oscillator and the bi-phasing power amplifier, and buffers the carrier generated by the voltage-controlled oscillator (VCO) to reduce a change occurring in the voltage-controlled oscillator by the bi-phasing operation. first buffer to pass to the paging power amplifier
Including, OOK transmitter. 9. The method of claim 8,
The bi-phasing power amplifier is
An OOK transmitter for generating the transmission signal by randomly changing the phase of the carrier in units of a period of the coded transmission sequence according to the control signal. 10. The method of claim 9,
The bi-phasing power amplifier is
An OOK transmitter for generating the transmission signal by randomly switching the phase of the carrier by 0 degrees or 180 degrees in a cycle unit of the coded transmission sequence. 9. The method of claim 8,
The data encoder
An OOK transmitter that encodes the input data into a preset sequence pattern (pre-determined sequence pattern). delete 9. The method of claim 8,
a second buffer for buffering the output of the first buffer
Further comprising, OOK transmitter. voltage controlled oscillator;
a buffer for buffering the carriers generated by the voltage controlled oscillator; and
The phase of the buffered carrier is randomly switched between two phases according to a control signal by a bi-phasing operation, corresponding to a pulse-the pulse is generated based on a transmission sequence encoding input data A bi-phasing power amplifier that generates a transmit signal to
including,
the buffer is
It is located between the voltage controlled oscillator and the bi-phasing power amplifier, and buffers the carrier generated by the voltage controlled oscillator in order to reduce a change occurring in the voltage controlled oscillator by the bi-phasing operation, and thereby the bi-phasing power amplifier. Forwarding to, OOK transmitter. 15. The method of claim 14,
The bi-phasing power amplifier is
OOK transmitter for generating a transmission signal corresponding to the pulse by randomly shifting the phase of the buffered carrier by 0 degrees or 180 degrees in period units of the coded transmission sequence. encoding the input data in the form of a transmission sequence;
generating a pulse based on the encoded transmission sequence;
generating a control signal for randomly switching a phase of a carrier between two phases in units of time of each element of the coded transmission sequence;
randomly switching the phase of the carrier generated by a voltage controlled oscillator according to the control signal by a bi-phasing operation;
buffering and transferring carriers generated in the voltage controlled oscillator to reduce a change occurring in the carrier by the bi-phasing operation;
generating a transmission signal using the buffered carrier, the phase-shifted carrier, and the pulse
comprising, a communication method. 17. The method of claim 16,
The step of randomly switching the phase of the carrier
Randomly shifting the phase of the carrier by 0 degrees or 180 degrees in time units of each element of the coded transmission sequence according to the control signal
Including, a communication method. delete encoding the input data in the form of a transmission sequence;
generating a pulse based on the encoded transmission sequence;
generating a control signal for randomly switching a phase of a carrier between two phases based on a time unit of each element of the coded transmission sequence;
randomly switching the phase of the carrier generated by a voltage controlled oscillator according to the control signal by a bi-phasing operation;
buffering the carrier to reduce changes occurring in the carrier by the bi-paging operation; and
generating a transmission signal using the buffered carrier, the phase-shifted carrier, and the pulse
Including, a communication method. 20. The method of claim 19,
The step of generating the transmission signal is
generating the transmission signal by randomly shifting the phase of the carrier by 0 degrees or 180 degrees in a cycle unit of the coded transmission sequence according to the control signal
Including, a communication method.

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