JP4356503B2 - Locating system, receiver, receiving method, receiving method and receiving method - Google Patents

Description

  The present invention relates to a position specifying system that detects a relative position change between objects, and more particularly, to a position specifying system that detects a relative position change between objects using weak radio, and a receiver and a receiving method. The present invention relates to a reception method and a reception method.

  More specifically, the present invention relates to a position identification system that detects a relative position change using communication of an extremely weak impulse train between objects, and a receiver, a reception method, a reception method, and a reception method.

  Information network sharing and device resource sharing can be efficiently realized by computer networking such as a LAN. Here, a wireless LAN is attracting attention as a system for releasing users from the conventional wired LAN connection. According to the wireless LAN, most of the wired cables can be omitted in a work space such as an office, so that a communication terminal such as a personal computer (PC) can be moved relatively easily.

  In recent years, the demand for wireless LAN systems has increased remarkably with the increase in speed and cost. In particular, the introduction of a personal area network (PAN) has been studied in order to construct a small-scale wireless network between a plurality of electronic devices existing around a person and perform information communication. For example, different radio communication systems and radio communication apparatuses are defined using frequency bands that do not require a license from a supervisory agency, such as 2.4 GHz band and 5 GHz band.

  In recent years, a method called “ultra-wide band (UWB) communication” for performing wireless communication by placing information on a very weak impulse train has attracted attention as a wireless communication system that realizes short-range ultrahigh-speed transmission, and its practical use. Is expected.

  In the United States, FCC (Federal Communication Commission) relaxed regulations on the UWB system in February 2002 (see, for example, Non-Patent Document 1). As the contents of deregulation, it is permitted to radiate radio waves having an output of −41.3 [dBm] from 3.1 GHz to 10.6 GHz (see FIG. 10). Currently, in IEEE802.15.3 and the like, a data transmission method having a packet structure including a preamble has been devised as an access control method for ultra-wideband communication (see, for example, Non-Patent Document 2).

  On the other hand, the UWB system has a high time resolution by using ultra-fine pulses, and can perform “ranging” for radar and positioning using this property. In particular, recent UWB communication can have both high-speed data transmission exceeding 100 Mbps and the original ranging function (see, for example, Patent Document 1).

  In the future, WPAN (Wireless Personal Access Network) of near field communication represented by UWB is expected to be installed in all home appliances and CE (Consumer Electronics) devices. Therefore, apart from high-speed data transmission, it is considered that the use of position information by ranging, such as navigation and near field communication (NFC), may create added value of radio, and distance measurement together with high-speed data transmission. It is considered desirable to implement the function.

JP 2002-51001 A Sasaki Shigenobu, Ikegami Tetsufumi, and Koda Toshitoshi "International Conference on UWB System and Technology (UWBST2002)" (SST2002-19, July 2002) http: // grouper. iee. org / groups / 802/15 / pub / SG4a. html

  An object of the present invention is to provide an excellent position identification system, a receiver, a reception method, and a reception method capable of detecting a relative position change between objects by using communication of an extremely weak impulse train between the objects. And providing a receiving method.

The present invention has been made in consideration of the above problems, and is a position specifying system that detects a relative position change between objects using a radio signal,
A transmitter configured to transmit a pair of pulse signals having a predetermined pulse width composed of a combination of positive and negative pulse components;
Generate a plurality of template signals shifted by half the pulse width, correlate the received waveform of the pulse signal from the transmitter and each template signal, and the correlation result in each template signal is a specific pattern And a receiver for detecting a change in the distance between the transmitter and the receiver based on a timing adjustment amount at the time of acquiring the synchronization,
It is a position specifying system characterized by comprising.

  However, “system” here refers to a logical collection of a plurality of devices (or functional modules that realize specific functions), and each device or functional module is in a single housing. It does not matter whether or not.

  Here, the receiver generates a template signal having a length equal to or longer than the pulse width of the pulse signal sent from the transmitter.

  The receiver uses a template waveform with a width greater than or equal to the received pulse width to perform correlation processing with the received waveform, but is not specifically intended to decode the received signal, and only needs to detect the presence of a pulse. So there is no problem. Further, by setting the template waveform to be equal to or larger than the reception pulse width, the template waveform can be configured with a low clock driving circuit, and power consumption can be reduced.

  The receiver may generate a template signal having a length equal to or longer than the pulse width as a digital rectangular wave.

  In such a case, the code generation circuit for generating the template waveform can be constituted by a digital circuit. Therefore, problems such as adjustment of the differentiator as in the case where the code generation circuit is constituted by an analog circuit can be solved. In addition, by configuring the code generation circuit with a digital circuit, it is possible to benefit from process technology such as high accuracy by increasing the clock speed and circuit scale.

  In the positioning system according to the present invention, the receiver has three types of template waveforms l (t−Δ), l (t), which have a width equal to or greater than the reception pulse width and are shifted in timing by half the reception pulse width Δ. l (t + Δ) is generated, each is multiplied by the received waveform, and further time integration is performed. In such a case, the integral d (0) of multiplication of the received pulse wave and the template waveform l (t) whose timing coincides is 0, but the template waveform l (t) whose timing is earlier by half the pulse width than this. The integral d (-Δ) of multiplication with -Δ) is negative, and the integral d (Δ) of multiplication with the template waveform l (t + Δ) delayed by half the pulse width is positive. Using such characteristics, synchronization can be acquired.

  That is, a pattern of d (−Δ) <0, d (0) = 0, d (Δ)> 0 (or d (−Δ)> 0, d (0) = 0, d (Δ) <0). Thus, acquisition of synchronization can be detected. If d (−Δ) = 0, d (0)> 0, d (Δ) = 0, the timing of the template signal is delayed, d (−Δ) = 0, d (0) <0, d If (Δ) <0, the reverse timing may be advanced.

  Advantageous Effects of Invention According to the present invention, an excellent position identification system, a receiver, a reception method, and a reception method that can detect a relative position change between objects using communication of an extremely weak impulse train between objects. And a receiving method can be provided.

  According to the position detection system of the present invention, the transmitter side can omit the pulse generator, the filter, and the amplifier as compared with the UWB transmitter, and the configuration of the antenna can be simplified. That is, the effect of reducing the design / manufacturing cost and size of the apparatus can be obtained.

  In addition, according to the position detection system of the present invention, the receiver side can directly use a rectangular wave signal generated by a digital circuit as a template waveform for correlation processing for acquiring synchronization with a received pulse. . Thus, by adopting a receiver configuration in which the analog circuit portion that is difficult to design and control is reduced, design / manufacturing costs can be reduced, and control for specifying the position can be simplified.

  Other objects, features, and advantages of the present invention will become apparent from more detailed description based on embodiments of the present invention described later and the accompanying drawings.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  The present invention relates to a position identification system that detects a relative position change between objects, and more specifically, a relative position change between objects by wirelessly communicating a very weak impulse train between the objects. The present invention relates to a position identification system to be detected.

  FIG. 1 schematically shows a configuration example of a general UWB system transmitter. The illustrated transmitter includes a clock generator 1, a PN signal generator 2, a pulse generator 3, a filter 4, an amplifier 5, an impedance matching circuit 6, and an antenna 7. According to this transmitter configuration, it is possible to detect a relative position change between objects by performing wireless communication by placing information on an extremely weak impulse train between the objects.

  First, the clock generator 1 generates a clock signal having a predetermined frequency. The PN signal generator 2 generates a rectangular wave according to a known PN code using a clock signal having a predetermined frequency output from the clock generator 1. When there is transmission data, the PN code is modulated by the transmission data. The pulse generator 3 outputs a pulse signal representing the digital signal input from the PN signal generator 2. As a method of pulse modulation, phase modulation that expresses 0/1 of transmission data by changing the phase of the pulse, timing modulation that expresses multiple values by changing the position of the pulse, or the like is used. The filter 4 receives the pulse train output from the pulse generator 3 and extracts only a signal component having a frequency that conforms to, for example, FCC regulations (see FIG. 10). The output of the filter 4 is amplified by the amplifier 5, further subjected to matching processing by the impedance matching circuit 6, and then sent to the wireless transmission path via the antenna 7.

  In the UWB transmission system, a signal sequence constituting a certain information bit is shown by repeatedly transmitting an impulse sequence having a predetermined pulse width at a predetermined pulse period. FIG. 2 shows a waveform example of a transmission signal sent from the transmitter shown in FIG.

  Here, in order to comply with FCC UWB regulations, a high frequency signal of 3.1 GHz to 10.6 GHz must be generated. For this reason, in the configuration of the transmitter circuit shown in FIG. 1, high-frequency pulses must be generated by the pulse generator 3 and power consumption increases. In addition, there is a problem that a transmission power loss is large because a filter 4 must be passed in order to extract a signal component that conforms to FCC regulations.

  FIG. 3 schematically shows another configuration example of the UWB system transmitter. The illustrated transmitter includes a clock generator 1, a PN signal generator 2, an impedance matching circuit 6, and an antenna 7.

  First, the clock generator 1 generates a clock signal having a predetermined frequency. The PN signal generator 2 generates a rectangular wave according to a known PN code using a clock signal having a predetermined frequency output from the clock generator 1.

  The generated rectangular wave is subjected to matching processing by the impedance matching circuit 6 and then transmitted to the wireless transmission path via the antenna 7.

  Here, the antenna 7 has a general property that the transmission signal is waveform-shaped. For example, a capacitance type antenna such as a dipole antenna has a characteristic of differentially outputting an input signal.

  Therefore, if the rectangular waveform output from the PN signal generator 2 is as shown in FIG. 4, the rectangular edge portion is emphasized by differentiation by being sent out by the capacitance type antenna 7, and as shown in FIG. It becomes. That is, without using a pulse generator, a pulse can be output by waveform shaping by the antenna 7 from a PN code or a known digital signal instead of the PN code.

  It should be noted that in the transmitter configuration shown in FIG. 2, the pulse generator 3, the filter 4, and the amplifier 5 are omitted as compared to the UWB transmitter shown in FIG. The absence of the filter 4 makes it impossible to extract only signal components having a frequency that conforms to FCC regulations, but this does not violate Japanese regulations.

  As can be seen from FIG. 10, unlike the UWB regulations in FCC, there is no limitation on the radiation frequency in Japan, so that no transmitter filter is required and the antenna configuration can be simplified. A weak pulse signal can be transmitted by radiating the rectangular wave output of the PN signal generator from the antenna as it is. That is, the effect of reducing the cost and size of the system can be obtained. Further, since the transmitter shown in FIG. 3 does not use a carrier wave, it differs from conventional CDMA.

  On the other hand, on the receiver side, a weak pulse signal output from the transmitter shown in FIG. 1 or FIG. 2 is received and subjected to demodulation / decoding processing to detect a relative position change with respect to the transmitter. be able to.

  FIG. 6 schematically shows a configuration example on the receiver side of the position specifying system. As shown, the receiver includes an antenna 11, a filter 12, a low noise amplifier 13, a correlator 14, an amplifier 15, a template waveform generator 16, an integrator 17, a clock generator 18, and a PN. And a code generator 19.

  The signal received by the antenna 11 passes through the filter 12 to remove frequency components other than the transmission pulse signal component. The signal that has passed through the filter 12 is further amplified by the low noise amplifier 13 and input to the first terminal of the correlator 14.

  On the other hand, the clock generator 18 outputs a clock signal having a predetermined frequency, and the PN code generator 19 outputs a PN code common to the transmitter side or a known digital signal replacing the PN code. The template waveform generator 16 is composed of an analog circuit, and generates an analog template waveform for correlating with the received waveform based on the clock signal and a digital rectangular signal such as a PN code. The clock generator 18 is assumed to be a variable frequency type clock generator such as a VCTCXO (current controlled oscillator).

  The correlator 14 multiplies the received waveform input from the first terminal by the template waveform input from the second terminal, and outputs the result to the amplifier 15. The amplifier 15 amplifies this output signal, and the integrator 17 further integrates this with time to output an integrated value, which is fed back to the clock generator 18.

  Since the correlation between the received waveform and the template waveform corresponds to the amount of timing deviation between the received waveform and the template waveform, the clock generator 18 causes the correlation value to become zero according to the integrated output from the integrator 17. Adjust the clock generation timing.

  FIG. 7A shows a waveform of a signal received by the receiver. FIG. 7B shows an example of a template waveform generated in order to perform correlation processing with the received waveform in the receiver. FIG. 7C shows the correlation output between the received waveform and the template waveform output from the correlator 14.

  Here, when the received waveform is expressed as a function r (t) of time, the template waveform l (t) is expressed as l (t) = r (t−Δ) −r (t + Δ). Here, δ is a timing shift amount between the received waveform and the template waveform. The correlation between the received waveform and the template waveform corresponds to the amount of timing deviation between the received waveform and the template waveform, and the output d (Δ) of the correlator 14 is expressed by the following equation.

  As shown in FIG. 7C, if the timing of the template waveform of the received pulse waveform matches (synchronizes), the output waveform of the correlator 14 becomes zero. Therefore, an operation of tracking the zero-cross point of the output of the integrator 17 and advancing the timing of the clock generator 18 when the output of the integrator 17 shows a positive value and delaying the timing when showing a negative value. By doing so, synchronization can be obtained.

  Such a control loop is called a delay locked loop. When a correlation is obtained between the template waveform and the received waveform, and synchronization of the pulse position and phase is acquired, synchronization is maintained in the delay lock loop.

  On the other hand, when the distance between the transmitter and the receiver changes, a timing shift occurs again between the template waveform and the received waveform. That is, the amount of timing deviation corresponds to the amount of change in the relative position between the transceivers. The amount of adjustment of this clock generation timing can be taken out and the change in the distance between the transmitter and the receiver can be measured. For example, after calibrating the synchronization timing between the transmitter and the receiver at a certain time, the position shift of the transmitter with respect to the receiver is detected or tracked by continuously measuring the timing deviation. be able to. This is the mechanism of the location system using UWB communication.

  Here, in the receiver shown in FIG. 6, the template waveform generator 16 is composed of an analog circuit, and is analog for correlating with a received waveform based on a digital rectangular signal such as a clock signal and a PN code. A template waveform is generated (refer to, for example, US Pat. No. 5,365,240 for the point of generating an analog pulse waveform). However, the analog circuit is difficult to design, and in this case, control such as adjustment of the differentiator becomes difficult, and there is a problem that the cost of equipment design and production increases on the receiver side. Incidentally, in the transmitter shown in FIG. 3, since the antenna substantially plays the role of a differentiator, an analog circuit portion for transmitting the differentiated pulse waveform is reduced.

  FIG. 8 schematically shows another configuration example of the receiver of the position specifying system. As shown, the receiver includes an antenna 21, a filter 22, a low noise amplifier (LNA) 23, a multiplier 24, an amplifier 25, an integrator 26, a clock generator 27, and a code generator 28. Composed. The receiver shown in the figure is greatly different from the receiver shown in FIG. 6 in that an analog circuit portion for generating a template waveform is saved. The receiver shown in FIG. 8 is mainly configured to detect a change in position relative to the transmitter, and is particularly considered to restore the data by demodulating and decoding the received signal. Absent. In addition, as shown in FIG. 2 or 5, the transmitter transmits a pair of pulse signals having positive and negative components as a unit.

  The signal received by the antenna 21 passes through the filter 22, and frequency components other than the transmission pulse signal component are removed. The signal that has passed through the filter 22 is amplified by the low noise amplifier 23 and input to the first terminal of the multiplier 4.

  On the other hand, a clock signal having a predetermined frequency is output from the clock generator 26 and input to the code generator 28. The clock generator 26 is assumed to be a variable frequency type clock generator such as a VCTCXO (current controlled oscillator). The code generator 28 is composed of a digital circuit, and three types of digital rectangles having a width equal to or greater than the reception pulse width, the timing of which is shifted by half of the pulse width of a pair of pulse signals having positive and negative components transmitted from the transmitter. Generate a template signal consisting of waves. The output of the code generator 28 is input to the second terminal of the multiplier 24.

  The multiplier 24 multiplies the received waveform input from the first terminal by the three types of template waveforms shifted in timing input from the second terminal, and outputs the result from the third terminal. The output of the multiplier 24 is amplified by an amplifier 25, and further integrated by time by an integrator 26, which is fed back to the clock generator 27.

  The clock generator 27 adjusts the clock generation timing according to the output of the integrator 6. The distance of the transmission / reception period is measured by this timing adjustment amount. A mechanism for adjusting the clock generation timing will be described with reference to an operation timing chart in the receiver shown in FIG.

  9 shows the received signal r from the transmitter. As described above, the transmitter transmits a pair of pulse signals having positive and negative components as a unit. The pair of pulse signals may be configured in the order of positive and negative as shown in the drawing, or may be configured in the order of negative and positive.

  On the other hand, on the receiver side, the code generator 28 has three types of template signals l (t−Δ) whose timings are shifted by a time Δ corresponding to half the pulse width of the pulse signal transmitted from the transmitter. , L (t), l (t + Δ). Each of these template signals is composed of a digital rectangular wave as shown in the second to fourth stages of FIG. 8, and has a width equal to or greater than the reception pulse width.

  In the multiplier 24, the received waveform of the pulse signal sent from the transmitter and three types of template waveforms l (t−Δ), l (t), l (t + Δ) whose timing is shifted by half Δ of the received pulse width. ) Respectively. The output of the multiplier 24 is amplified by the amplifier 25, time integrated by the integrator 26, and three types of integration results as shown below are output.

  Here, since the template waveform generated by the code generator 28 has a width equal to or larger than the reception pulse width, the integration of multiplication of the received pulse wave and the template waveform l (t) having the same timing is 0. The integration of multiplication with the template waveform l (t−Δ) whose timing is earlier by half the pulse width is negative, and the integration of multiplication with the template waveform l (t + Δ) whose timing is later by half the pulse width becomes positive.

  The zero cross point of the output of the integrator 27 is tracked to obtain the synchronization timing with the received signal. At this time, three types of integration results obtained by multiplying the received waveform by three types of template waveforms l (t−Δ), l (t), and l (t + Δ) whose timings are shifted by half Δ of the received pulse width are expressed by the above equations. , D (−Δ) <0, d (0) = 0, d (Δ)> 0 (or d (−Δ)> 0, d (0) = 0, d (Δ) <0 ), The acquisition of synchronization can be detected.

  If d (−Δ) = 0, d (0)> 0, d (Δ) = 0, the timing of the template signal of the clock generator 27 is delayed, and d (−Δ) = 0, d ( If 0) <0 and d (Δ) <0, the timing of the clock generator 27 is reversed.

  As described above, when the correlation is obtained between the template waveform and the received waveform by the delay lock loop and the synchronization of the pulse position and the phase is acquired, the delay lock loop holds the synchronization.

  On the other hand, when the distance between the transmitter and the receiver changes, a timing shift occurs again between the template waveform and the received waveform. That is, the amount of timing deviation corresponds to the amount of change in the relative position between the transceivers. The amount of adjustment of this clock generation timing can be taken out and the change in the distance between the transmitter and the receiver can be measured. For example, after calibrating the synchronization timing between the transmitter and the receiver at a certain time, the position shift of the transmitter with respect to the receiver is detected or tracked by continuously measuring the timing deviation. be able to.

  As described above, the receiver shown in FIG. 8 has three types of template waveforms l (t−Δ) and l (t) having a width equal to or larger than the reception pulse width and shifted in timing by half Δ of the reception pulse width. , L (t + Δ) is multiplied by the received waveform, and the integration of multiplication of the received pulse wave and the template waveform l (t) whose timing is the same is 0, and the template waveform l whose timing is earlier by half the pulse width than this. Synchronous acquisition is performed by utilizing the characteristic that the integral of multiplication with (t−Δ) is negative and the integral of multiplication with template waveform l (t + Δ) whose timing is delayed by half the pulse width is positive.

  Here, since the template waveform used for the correlation process is a digital rectangular wave, the code generation circuit 28 that generates the template waveform can be configured by a digital circuit. Therefore, as shown in FIG. 6, when the code generation circuit is composed of an analog circuit, it becomes difficult to control the differential, such as adjustment of the differentiator, and the problem that the cost of equipment design and production increases on the receiver side is solved. can do. By configuring the code generation circuit 28 with a digital circuit, it is possible to receive the benefits of process technology such as high accuracy by increasing the clock speed and circuit scale.

  Further, in the receiver shown in FIG. 8, correlation processing with a received waveform is performed using a template waveform having a width equal to or larger than the received pulse width, but the received signal is demodulated and decoded to restore data itself. This is not a problem because only the presence of a pulse is detected. Further, by setting the template waveform to be equal to or larger than the reception pulse width, the code generator 28 can be configured by a low clock drive circuit, and power consumption can be reduced.

  By combining the transmitter as shown in FIG. 3 and the receiver as shown in FIG. 8, a position specifying system having a simple circuit configuration can be constructed. Therefore, the position specifying system can be mounted not only on the information communication device but also on various home appliances and CE devices.

  The present invention has been described in detail above with reference to specific embodiments. However, it is obvious that those skilled in the art can make modifications and substitutions of the embodiment without departing from the gist of the present invention. That is, the present invention has been disclosed in the form of exemplification, and the contents described in the present specification should not be interpreted in a limited manner. In order to determine the gist of the present invention, the claims section described at the beginning should be considered.

FIG. 1 is a diagram schematically showing a configuration example (conventional example) of a UWB system transmitter. FIG. 2 is a diagram illustrating a waveform example of a transmission signal transmitted from the transmitter illustrated in FIG. FIG. 3 is a diagram schematically illustrating another configuration example of the transmitter for the UWB system. FIG. 4 is a diagram showing an example of a rectangular waveform output from the PN signal generator 2. FIG. 5 is a diagram showing an example of a waveform of an antenna output signal by the transmitter shown in FIG. FIG. 6 is a diagram schematically illustrating a configuration example on the receiver side of the position specifying system. FIG. 7 is a diagram illustrating an example of a reception waveform, a template waveform, and a correlation output thereof in the receiver illustrated in FIG. FIG. 8 is a diagram schematically illustrating another configuration example of the receiver of the position specifying system. FIG. 9 is a diagram showing an operation timing chart in the receiver shown in FIG. FIG. 10 is a diagram showing a comparison between the regulation value for weak radio in Japan and the UWB regulation value for the radiation level in FCC.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Clock generator 2 ... PN signal generator 3 ... Pulse generator 4 ... Filter 5 ... Amplifier 6 ... Impedance matching circuit 7 ... Antenna 11 ... Antenna 12 ... Filter 13 ... Low noise amplifier 14 ... Correlator 15 ... Amplifier 16 ... Template waveform generator 17 ... Integrator 18 ... Clock generator 19 ... PN code generator 21 ... Antenna 22 ... Filter 23 ... Low noise amplifier 24 ... Multiplier 25 ... Amplifier 26 ... Integrator 27 ... Clock generator 28 ... Waveform Generator

Claims (9)

A location system that detects relative position changes between objects using wireless signals,
A transmitter configured to transmit a pair of pulse signals having a predetermined pulse width composed of a combination of positive and negative pulse components;
By generating a plurality of template signals shifted by half the pulse width, correlating the received waveform of the pulse signal from the transmitter with each template signal, and the correlation result in each template signal becomes a specific pattern A receiver that acquires synchronization and detects a change in distance between the transmitter and receiver based on a timing adjustment amount at the time of acquiring synchronization;
Equipped with,
Since d (−Δ) <0, d (0) = 0, and d (Δ)> 0, acquisition of synchronization is detected, and d (−Δ) = 0, d (0)> 0, d ( If Δ) = 0, the synchronization timing of the template signal is delayed, and if d (−Δ) = 0, d (0) <0, d (Δ) <0, the synchronization timing is advanced.
A location system characterized by that. The receiver generates a template signal having a length equal to or longer than the pulse width;
The position specifying system according to claim 1. The receiver generates a template signal composed of a digital rectangular wave.
The position specifying system according to claim 1. A receiver for detecting a relative change in position with a transmitter,
Receiving means for receiving a pair of pulse signals having a predetermined pulse width composed of a combination of positive and negative pulse components transmitted from a transmitter;
Template signal generating means for generating a plurality of template signals shifted by half of the pulse width;
Correlation processing means for correlating the received waveform of the pulse signal from the transmitter and each template signal;
Synchronization acquisition means for acquiring synchronization when the correlation result in each template signal becomes a specific pattern;
Ranging means for detecting a change in distance between the transmitter and the receiver based on a timing adjustment amount at the time of obtaining synchronization by the synchronization obtaining means;
Comprising
The template signal generation means generates three types of template waveforms l (t−Δ), l (t), and l (t + Δ) having a width equal to or greater than the reception pulse width and shifted in timing by half Δ of the reception pulse width. And
The correlation processing means time-integrates multiplication results of the three types of template waveforms l (t−Δ), l (t), l (t + Δ) and the received waveform,
The synchronization acquisition means detects acquisition of synchronization when d (−Δ) <0, d (0) = 0, d (Δ)> 0, and d (−Δ) = 0, d (0 )> 0, d (Δ) = 0, delay the synchronization timing of the template signal, and d (−Δ) = 0, d (0) <0, d (Δ) <0, advance the synchronization timing. ,
A receiver characterized by that. The template signal generating means generates a template signal having a length equal to or longer than the pulse width;
The receiver according to claim 4. The template signal generating means generates a template signal composed of a digital rectangular wave;
The receiver according to claim 4 . A receiving method for detecting a relative position change with a transmitter, comprising:
A receiving step for receiving a pair of pulse signals having a predetermined pulse width and consisting of a combination of positive and negative pulse components transmitted from a transmitter;
A template signal generating step for generating a plurality of template signals shifted by half of the pulse width;
A correlation processing step for correlating the received waveform of the pulse signal from the transmitter with each template signal;
A synchronization acquisition step of acquiring synchronization by the correlation result in each template signal becoming a specific pattern;
A ranging step for detecting a change in distance between the transmitter and the receiver based on a timing adjustment amount when acquiring synchronization in the synchronization acquisition step;
Have
In the template signal generation step, three types of template waveforms l (t−Δ), l (t), and l (t + Δ) having a width equal to or greater than the reception pulse width and shifted by half Δ of the reception pulse width are generated. And
In the correlation processing step, the multiplication results of the three types of template waveforms l (t−Δ), l (t), l (t + Δ) and the received waveform are respectively integrated,
In the synchronization acquisition step, when d (−Δ) <0, d (0) = 0, d (Δ)> 0, acquisition of synchronization is detected, and d (−Δ) = 0, d (0 )> 0, d (Δ) = 0, delay the synchronization timing of the template signal, and d (−Δ) = 0, d (0) <0, d (Δ) <0, advance the synchronization timing. ,
And a receiving method. In the template signal generation step, a template signal having a length equal to or longer than the pulse width is generated.
The receiving method according to claim 7. In the template signal generation step, a template signal composed of a digital rectangular wave is generated.
The receiving method according to claim 7.

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