Semiconductor devices and physical quantity measuring devices

Abstract

To provide a technique which can perform measurement independently of a measurement distance.SOLUTION: A semiconductor device includes: a transmission device which radiates a transmission signal generated by modulating a carrier wave with a modulation signal to a measurement object from an antenna; and a reception device which generates a demodulation signal by receiving the transmission signal through the measurement object with the antenna and demodulating it and performs processing on the demodulation signal. The transmission device is configured to start modulation in the first phase. The reception device is configured to store a physical quantity corresponding to the first phase and phase change amount in advance, estimate the modulation signal start timing at which the reception signal switches from the non-modulation period to the modulation period on the basis of the waveform of the demodulation signal, calculate the second phase which is the phase at the modulation start timing, calculate the change amount to the second phase on the basis of the stored first phase, and determine the physical quantity corresponding to the change amount on the basis of the physical quantity corresponding to the stored phase change amount.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present disclosure relates to a semiconductor device, and is applicable to, for example, a semiconductor device that detects a change in a physical quantity such as a moisture content, and a physical quantity measuring device.

Background Art

[0002] Patent Document 1 discloses a device that transmits radio waves toward an object, receives reflected waves from the object, and analyzes the received signal to measure the state or physical characteristics of the object, that is, the distance to the object, the relative speed to the object, the shape, the internal structure, etc.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Depending on the configurations of the device that transmits radio waves and the device that receives the reflected waves, correct measurement may not be possible when the distance to the measurement object varies.

[0005] Other problems and novel features will become apparent from the description of this specification and the accompanying drawings.

Means for Solving the Problems

[0006] A brief overview of some of the representative features of this disclosure is as follows: The semiconductor device comprises a transmitting device that generates a transmission signal by modulating a carrier wave with a modulation signal and radiates it from an antenna toward an object to be measured, and a receiving device that receives the transmission signal that has passed through the object to be measured with an antenna, demodulates it to generate a demodulated signal, and processes the demodulated signal. The transmitting device is configured to start modulation in a first phase. The receiving device is configured to store in advance the first phase and physical quantities corresponding to the phase change amount, estimate the modulation signal start timing at which the received signal switches from the unmodulated period to the modulated period based on the waveform of the demodulated signal, calculate the second phase which is the phase at the modulation start timing, calculate the amount of change to the second phase based on the stored first phase, and determine the physical quantity corresponding to the amount of change based on the stored physical quantity corresponding to the phase change amount. [Effects of the Invention]

[0007] The above semiconductor device enables measurement that is independent of the measurement distance. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a diagram showing the configuration of a device for detecting the state of an object to be measured in an embodiment. [Figure 2] Figure 2 is a front view showing the configuration of the object to be measured. [Figure 3] Figure 3 shows the frequency-phase characteristics. [Figure 4] Figure 4 is a block diagram showing the configuration of the semiconductor device shown in Figure 1. [Figure 5] Figure 5 is a waveform diagram showing the operation of the semiconductor device shown in Figure 4. [Figure 6] Figure 6 is a block diagram showing the configuration of a device for detecting the state of an object being measured in a comparative example. [Figure 7] Figure 7 is a waveform diagram showing the operation of the device shown in Figure 6. [Figure 8] Figure 8 is a waveform diagram showing the operation of the device shown in Figure 4. [Figure 9]Figure 9 is a block diagram showing the configuration of a semiconductor device in the fourth modified example. [Figure 10] Figure 10 is a waveform diagram showing the operation of the semiconductor device shown in Figure 9. [Figure 11] Figure 11 is a waveform diagram showing the operation of the modulation signal generation unit shown in Figure 9. [Figure 12] Figure 12 is a waveform diagram showing the operation of the demodulation unit shown in Figure 9. [Figure 13] Figure 13 is a waveform diagram showing the operation of the modulation signal generation unit in the comparative example of the fourth modified example. [Figure 14] Figure 14 is a waveform diagram showing the operation of the demodulator in the comparative example of the fourth modified example. [Modes for carrying out the invention]

[0009] Embodiments and comparative examples will be described below with reference to the drawings. However, for the sake of clarity, the following descriptions and drawings have been omitted and simplified as appropriate. Also, the same reference numerals are used for identical components, and repeated explanations may be omitted.

[0010] An overview of the embodiment will be described using Figures 1 to 3. Figure 1 is a diagram showing the configuration of a device for detecting the state of an object to be measured in the embodiment. Figure 2 is a front view showing the configuration of the object to be measured. Figure 3 is a diagram showing the frequency-phase characteristics. In Figure 3, the horizontal axis is frequency (F), and the vertical axis (P) is phase.

[0011] In this embodiment, the semiconductor device 10 measures physical quantities such as moisture content by irradiating an object to be measured, such as a battery-less (semiconductor chip-less) sensor, with radio waves or sound waves to measure the frequency-phase characteristics of the object's reflection or transmission characteristics. When radio waves are irradiated, for example, moisture detection is possible. When sound waves are irradiated, for example, acoustic characteristics can be measured.

[0012] The semiconductor device 10 includes a transmission device (TX) 110 connected to the antenna 20 and a reception device (RX) 120 connected to the antenna 30. The transmission device (TX) 110 and the reception device (RX) 120 perform, for example, ultra-wideband (UWB) wireless communication. In UWB, a very wide frequency band from several hundred MHz to several GHz is used. According to the definition of the Federal Communications Commission (FCC) of the United States, UWB is a wireless communication method that performs transmission and reception using an extremely wide bandwidth where the 10 dB ratio bandwidth is 20% or more of the center frequency, or 500 MHz or more. The semiconductor device 10 may be configured to include the transmission device 110 and the reception device 120 on one semiconductor chip, or may be configured to include them on separate semiconductor chips.

[0013] The measurement object 40 is composed of a metamaterial. A metamaterial is a structure that exhibits an electromagnetic response that does not exist in natural substances, such as a periodic structure on the order of the wavelength. A structure with a certain shape below the periodic wavelength has a phase of the reflected wave or transmitted wave that changes with frequency (the frequency-phase characteristic changes). The periodic structure is configured, for example, by periodically arranging the conductor patterns 42 on one side of a printed circuit board 41 in which conductors (metals, such as copper) are provided on both sides of an insulator (dielectric) substrate in an array. The conductor pattern 42 is formed, for example, in a non-closed loop shape as shown in FIG. 2.

[0014] As shown in FIG. 3, the frequency-phase characteristic of the measurement object 40 changes depending on the humidity (moisture content). As indicated by the arrow, when the moisture decreases, the frequency (F) at which the phase (P) changes increases. By measuring the amount of change in the phase, the moisture content can be measured. The semiconductor device 10, the antennas 20 and 30, and the measurement object 40 constitute a physical quantity measuring device.

[0015] Details of the configuration of the semiconductor device 10 in the embodiment will be described with reference to FIG. 4. FIG. 4 is a block diagram showing the configuration of the semiconductor device shown in FIG. 1.

[0016] The transmitting device 110 includes a modulation signal generation unit (MSG) 111 that outputs a frequency-modulated signal, and an RF unit 112 that supplies an RF signal to the antenna 20. The antenna 20 radiates the RF signal as a transmission signal (WT) to the object to be measured (TMO) 40.

[0017] The receiving device 120 includes an RF unit 121 that amplifies the received signal (WR) received by the antenna 30, a demodulation unit (DMD) 122 that demodulates and digitizes the signal, and an arithmetic unit (ART) 123. The antenna 30 receives the signal reflected by the object to be measured 40 as the received signal (WR).

[0018] The calculation unit 123 includes a modulation timing calculation unit (MST) 123a, a θRX calculation unit (PRX) 123b, a frequency phase characteristic calculation unit (FPC) 123c, and a physical quantity calculation unit (MC) 123d.

[0019] The memory unit 123e stores the relationship between the moisture content of the object 40 being measured and the frequency phase characteristics of the radio wave reflection or transmission characteristics of the object 40 being measured. The memory unit (MRY) 123e may be provided outside the calculation unit 123.

[0020] The frequency phase characteristics of the radio wave reflection or transmission characteristics of the object being measured 40 change depending on the amount of moisture it contains. The object being measured 40 is composed of a conductor pattern as shown in Figure 2, for example.

[0021] The operation of the semiconductor device 10 in this embodiment will be explained using Figure 5. Figure 5 is a waveform diagram showing the operation of the semiconductor device shown in Figure 4. In Figure 5, the horizontal axis represents time (t), and the vertical axis represents voltage (V).

[0022] The modulation signal generation unit 111 starts outputting an unmodulated signal at timing (T11). The modulation signal generation unit 111 starts outputting a modulated signal at timing (T12). The phase at timing (T12) is the known θTX. In Figure 5, θTX = 0 degrees.

[0023] The received signal (WR) is the signal that arrives at the receiving device 120 after the transmitted signal (WT) has been reflected or transmitted by the object being measured 40, and is a signal that is delayed by a time delay amount (D1) from the transmitted signal (WT).

[0024] The modulation timing calculation unit 123a estimates the timing (T22) at which modulation begins, which is the transition from the unmodulated period (UMP) to the modulated period (MP) of the received signal (WR).

[0025] The θRX calculation unit 123b calculates the phase (θRX) at the estimated modulation start timing (T22). In Figure 5, θRX = -90 degrees.

[0026] The frequency phase characteristic calculation unit 123c calculates the amount of change from θTX to θRX.

[0027] The physical quantity calculation unit 123d determines the amount of moisture by referring to the value obtained from the frequency phase characteristic calculation unit 123c (the amount of change from θTX to θRX) and the data stored in the storage unit 123e.

[0028] Each element shown in the diagram as a functional block that performs the various processes described above can be comprised of a CPU (Central Processing Unit), memory, or other circuits in hardware terms. Furthermore, it is implemented in software terms by programs loaded into memory. Therefore, these functional blocks can be composed of hardware alone, software alone, or a combination of both, and are not limited to any one of these configurations.

[0029] <Comparative Example> To further clarify this embodiment, the present discloser will describe, with reference to Figures 6 and 7, a technology (comparative example) that the present discloser has considered prior to this disclosure. Figure 6 is a block diagram showing the configuration of a device for detecting the state of an object to be measured in a comparative example. Figure 7 is a waveform diagram showing the operation of the device shown in Figure 6. In Figures 6 and 7, the horizontal axis represents time (t), and the vertical axis represents the electric field (E).

[0030] As shown in Figure 6, the transmitting device 110 in the comparative example includes an unmodulated signal generation unit (USG) 113 that outputs an unmodulated signal, and an RF unit 112 that supplies an RF signal to the antenna 20. The unmodulated signal generation unit 113 outputs a reference signal (RS) to the receiving device 120.

[0031] As shown in Figure 6, the receiving device 120 in the comparative example comprises an RF unit 121, a phase detector (PD) 124, an analog-to-digital converter (ADC) 125 that converts to a digital signal, and an arithmetic unit (ART) 123. The RF unit 121 amplifies the received signal (WR) received by the antenna 30. The phase detector 124 outputs the phase difference between the received signal (WR) and the reference signal (RS). The arithmetic unit 123 calculates the amount of moisture from the phase difference detected by the phase detector 124.

[0032] In Figure 7, (a) is the output waveform of the antenna 20 of the transmitter 110. (b) is the input waveform of the object to be measured 40, and its phase is different from (a) due to a delay (A) in the path. That is, the phase is delayed due to the time delay (Dab) from the transmitter 110 to the object to be measured 40. (c) is the output waveform of the object to be measured 40, and its phase is different from (b) due to a phase change (B) at the object to be measured 40. (d) is the input waveform of the antenna 20 of the receiver 120, and its phase is different from (c) due to a delay (C) in the path. That is, the phase is delayed due to the time delay (Dcd) from the object to be measured 40 to the receiver 120.

[0033] In the comparative example, the phase difference between the reference signal (RS) supplied from the transmitter 110 to the receiver 120 and the received signal (WR) supplied from the antenna 30 of the receiver 120 is measured. As a result, as shown in Figure 7, the measurement result (MR) of the comparative example includes not only the phase change amount (PC) at the object being measured 40, but also the phase change amount due to time delay (Dab) and the phase change amount due to time delay (Dcd).

[0034] Therefore, in the comparative example, there is a problem in that accurate measurement is not possible when the distance from the semiconductor device 10 to the object to be measured 40 changes.

[0035] Next, the operation of the physical quantity measuring device in the embodiment will be explained using Figure 8. Figure 8 is a waveform diagram showing the operation of the device shown in Figure 4.

[0036] In Figure 8, (a) is the output waveform of the antenna 20 of the transmitter 110. (b) is the input waveform of the object under measurement 40, and its phase is different from (a) due to a delay (A) in the path. That is, the phase is delayed due to the time delay (Dab) from the transmitter 110 to the object under measurement 40. (c) is the output waveform of the object under measurement 40, and its phase is different from (b) due to a phase change (B) at the object under measurement 40. (d) is the input waveform of the antenna 20 of the receiver 120, and its phase is different from (c) due to a delay (C) in the path. That is, the phase is delayed due to the time delay (Dcd) from the object under measurement 40 to the receiver 120.

[0037] In this embodiment, the phase is measured at the timing (T22) when modulation begins, which is the transition from the unmodulated period to the modulated period. Therefore, the measurement result (MR) includes only the phase change amount (PC) at the object being measured 40, and does not include the phase change amount due to time delay (Dab) or the phase change amount due to time delay (Dcd). Even if the distance from the semiconductor device 10 to the object being measured 40 changes, the phase change amount at the object being measured 40 can be measured accurately.

[0038] In other words, the receiving device 120 calculates the frequency phase characteristics from the received signal rather than comparing it with the transmitted signal. Therefore, even if the distance from the transmitting device 110 to the receiving device 120 via the object to be measured 40 changes, it is possible to accurately measure the frequency characteristics of the object to be measured 40.

[0039] Furthermore, since the receiving device 120 does not use the transmission signal sent from the transmitting device 110, a physical connection between the transmitting device 110 and the receiving device 120 is unnecessary.

[0040] Since the sensor, which is the object to be measured in this embodiment, is composed of a conductive pattern, it does not require a power source such as a battery. Furthermore, the sensor in this embodiment is inexpensive. In addition, it is easy to ensure water resistance in the sensor in this embodiment.

[0041] <Variation> The following are some representative examples of modifications of the embodiments. In the following descriptions of modifications, the same reference numerals as in the embodiments described above may be used for parts having the same configuration and function as those described in the embodiments described above. Furthermore, the descriptions of such parts may be appropriately referenced from the embodiments described above, to the extent that they do not contradict the technical standards. In addition, some of the embodiments described above, and all or some of the modifications, may be applied in combination as appropriate, to the extent that they do not contradict the technical standards.

[0042] (First torture) In the embodiment, the semiconductor device 10 calculates the phase change amount using the phase of the modulation start timing when switching from the unmodulated period (UMP) to the modulated period (MP). On the other hand, in the first modified example, the semiconductor device 10 calculates the phase change amount using the phase of the modulation end timing when switching from the modulated period (MP) to the unmodulated period (UMP).

[0043] The modulation signal generation unit 111 of the transmitting device 110 terminates modulation at a first timing (first phase).

[0044] The storage unit 123e of the receiving device 110 stores in advance the amount of moisture corresponding to the first phase and the amount of phase change. The modulation timing calculation unit 123a estimates the modulation termination timing at which the received signal (WR) switches from the modulation period (MP) to the unmodulated period (UMP) based on the waveform of the demodulated signal. The θRX calculation unit 123b calculates the second phase, which is the phase at the modulation termination timing (second timing). The frequency phase characteristic calculation unit 123c calculates the amount of change to the second phase based on the first phase stored in the storage unit 123e. The physical quantity calculation unit 123d determines the amount of moisture corresponding to the change based on the amount of moisture corresponding to the amount of phase change stored in the storage unit 123e.

[0045] (Second variation) In the embodiment, the semiconductor device 10 calculates the phase change amount using the phase of the modulation start timing when it switches from the unmodulated period (UMP) to the modulated period (MP). On the other hand, in the second modified example, the semiconductor device 10 calculates the phase change amount using the phase of a predetermined time-shifted timing from the modulation start timing when it switches from the unmodulated period (UMP) to the modulated period (MP).

[0046] The modulation signal generation unit 111 of the transmitting device 110 modulates the signal so that it reaches a first phase at a timing that is first time-shifted from the modulation start timing.

[0047] The storage unit 123e of the receiving device 110 stores in advance the amount of moisture corresponding to the first time, the first phase, and the amount of phase change. The modulation timing calculation unit 123a estimates a timing that is one time shifted from the modulation start timing, when the received signal (WR) switches from the unmodulated period (UMP) to the modulated period (MP), based on the waveform of the demodulated signal. The θRX calculation unit 123b calculates the second phase, which is the phase at the timing that is one time shifted from the modulation start timing. The frequency phase characteristic calculation unit 123c calculates the amount of change to the second phase based on the first phase stored in the storage unit 123e. The physical quantity calculation unit 123d determines the amount of moisture corresponding to the change based on the amount of moisture corresponding to the amount of phase change stored in the storage unit 123e.

[0048] (Third variation) In the embodiment, the semiconductor device 10 calculates the phase change amount using the phase of the modulation start timing when it switches from the unmodulated period (UMP) to the modulated period (MP). On the other hand, in the third modified example, the semiconductor device 10 calculates the phase change amount using the phase of a predetermined time-shifted timing from the modulation end timing when it switches from the modulated period (MP) to the unmodulated period (UMP).

[0049] The modulation signal generation unit 111 of the transmitting device 110 modulates the signal so that it reaches a first phase at a timing that is first time-shifted from the modulation end timing.

[0050] The storage unit 123e of the receiving device 110 stores in advance the amount of moisture corresponding to the first time, the first phase, and the amount of phase change. The modulation timing calculation unit 123a estimates a timing that is shifted by one time from the modulation end timing, when the received signal (WR) switches from the modulation period (MP) to the unmodulated period (UMP), based on the waveform of the demodulated signal. The θRX calculation unit 123b calculates the second phase, which is the phase at the timing that is shifted by one time from the modulation end timing. The frequency phase characteristic calculation unit 123c calculates the amount of change to the second phase based on the first phase stored in the storage unit 123e. The physical quantity calculation unit 123d determines the amount of moisture corresponding to the change based on the amount of moisture corresponding to the amount of phase change stored in the storage unit 123e.

[0051] (Fourth variation) The configuration and operation of the semiconductor device 10 in the fourth modified example will be explained using Figures 9 and 10. Figure 9 is a block diagram showing the configuration of the semiconductor device in the fourth modified example. Figure 10 is a waveform diagram showing the operation of the semiconductor device shown in Figure 9. In Figure 10, the horizontal axis represents time (t), and the vertical axis represents voltage (V).

[0052] The semiconductor device in the fourth modified example has the same configuration as the semiconductor device 10 shown in Figure 4. However, the modulation signal generation unit 111 in the fourth modified example modulates and transmits multiple carrier waves. The modulation method and modulation signal may differ for each carrier wave.

[0053] As shown in Figure 9, the Modulation Signal Generator (MSG) 111 comprises a DSP (DSP) 1111 for generating digital signals, a DAC (digital-to-analog converter) 1112, a local oscillator (LO) 1113 for generating frequency conversion signals, and a frequency converter (FC) 1114 for performing frequency conversion.

[0054] The modulation signal generation unit 111 includes a frequency conversion unit 1114 for generating high-frequency signals. The frequency conversion unit 1114 generates a transmission signal (WT) from the intermediate frequency signal (WTIF) output by the digital-to-analog converter (DAC) 1112 and the frequency conversion signal (WTLO) output by the local oscillator (LO) 1113.

[0055] As shown in Figure 9, the demodulation unit (DMD) 122 includes a local oscillator (LO) 1223 that generates a frequency conversion signal, a frequency conversion unit (FC) 1224 that performs frequency conversion, an analog-to-digital converter (ADC) 1222, and a processing unit (DSP) 1221 that demodulates the output signal of the ADC. The frequency conversion unit (FC) 1224 generates an intermediate frequency signal (WRIF) from the received signal (WR) and the frequency conversion signal (WTLO) output by the local oscillator (LO) 1123.

[0056] As shown in Figure 10, the modulation signal generation unit 111 starts outputting an unmodulated signal at timing (T11), for example. The modulation signal generation unit 111 starts outputting a modulated signal at timing (T12). The phase at timing (T12) is a known θTX1. In the example shown in Figure 10, θTX1 = 0 degrees. The transmitted signal (WT1) has a carrier frequency of f1, where f1 is the frequency of one of the multiple carrier waves.

[0057] Furthermore, the modulation signal generation unit 111 starts outputting an unmodulated signal at timing (T31). The modulation signal generation unit 111 starts outputting a modulated signal at timing (T32). The phase at timing (T32) is the known θTX2. In the example shown in Figure 10, θTX2 = 0 degrees. The transmitted signal (WT2) has f2 as its carrier frequency, where f2 is the frequency of one of the other carrier waves among the multiple carrier waves. The difference (D3) between timing (T12) and timing (T32) is a known value. The difference between θTX1 and θTX2 (θTX1 - θTX2) is a known value.

[0058] The received signal (WR1) is the signal that arrives at the receiving device 120 after the transmitted signal (WT1) has been reflected or transmitted by the object being measured 40, and is a signal that is delayed by a time delay amount (D1) from the transmitted signal (WT1). The received signal (WR2) is the signal that arrives at the receiving device 120 after the transmitted signal (WT2) has been reflected or transmitted by the object being measured 40, and is a signal that is delayed by a time delay amount (D2) from the transmitted signal (WT2).

[0059] The modulation timing calculation unit 123a estimates the timing (T22) at which modulation begins, switching from the unmodulated period (UMP) to the modulated period (MP) of the received signal (WR1). The modulation timing calculation unit 123a estimates the timing (T42) at which modulation begins, switching from the unmodulated period (UMP) to the modulated period (MP) of the received signal (WR2). The difference (D4) between timing (T22) and timing (T42) is estimated.

[0060] The θRX calculation unit 123b calculates the phase (θRX1) of the transmitted signal (WT1) at the estimated modulation start timing (T22). In the example shown in Figure 10, θRX1 = -90 degrees. The θRX calculation unit 123b also calculates the phase (θRX2) of the transmitted signal (WT2) at the estimated modulation start timing (T42). In the example shown in Figure 10, θRX2 = -90 degrees.

[0061] The frequency phase characteristic calculation unit 123c calculates the amount of change from D3, D4, and the difference between θTX1 and θTX2 (0 degrees in the example shown in Figure 10) to the difference between θRX1 and θRX2 (0 degrees in the example shown in Figure 10).

[0062] The physical quantity calculation unit 123d determines the amount of moisture by referring to the value obtained from the frequency phase characteristic calculation unit 123c (the change from the difference between θTX1 and θTX2 to the difference between θRX1 and θRX2) and the data stored in the storage unit 123e.

[0063] The operation of the modulation signal generation unit 111 will be explained using Figure 11. Figure 11 is a waveform diagram showing the operation of the modulation signal generation unit shown in Figure 9.

[0064] The intermediate frequency signal (WTIF1) is one of the modulated signals included in the intermediate frequency signal (WTIF), and is a signal obtained by modulating a sine wave signal with the intermediate frequency (fIF1). The intermediate frequency signal (WTIF2) is one of the modulated signals included in the intermediate frequency signal (WTIF), and is a signal obtained by modulating a sine wave signal with the intermediate frequency (fIF2). The frequency conversion signal (WTLO) is a signal output by the local oscillator (LO) 1123.

[0065] The transmitted signal (WT1) is one of the modulated signals included in the transmitted signal (WT), and is a frequency-converted signal obtained by frequency conversion of the intermediate frequency signal (WTIF1) by the frequency conversion unit (FC) 1114. The transmitted signal (WT2) is one of the modulated signals included in the transmitted signal (WT), and is a frequency-converted signal obtained by frequency conversion of the intermediate frequency signal (WTIF2) by the frequency conversion unit (FC) 1114.

[0066] The modulation signal generation unit 111 starts outputting an unmodulated signal of the transmission signal (WT1) at timing (T11). The modulation signal generation unit 111 starts outputting a modulated signal of the transmission signal (WT1) at timing (T12). The phase of the intermediate frequency signal (WTIF1) at timing (T12) is θTIF1.

[0067] The modulation signal generation unit 111 starts outputting an unmodulated signal of the transmission signal (WT2) at timing (T31). The modulation signal generation unit 111 starts outputting a modulated signal of the transmission signal (WT2) at timing (T32). The phase of the intermediate frequency signal (WTIF2) at timing (T32) is θTIF2. Here, the time difference between timing (T12) and timing (T32) is D3.

[0068] The phase of the frequency conversion signal (WTLO) at timing (T12) is θTLO1. The phase of the frequency conversion signal (WTLO) at timing (T32) is θTLO2. The phase of the transmit signal (WT1) at timing (T12) is θTX1. The phase of the transmit signal (WT2) at timing (T32) is θTX2.

[0069] The transmitter 110 generates a transmission signal (WT1) and a transmission signal (WT2) such that the difference between θTX1 and θTX2 (θTX1-θTX2) is a predetermined value.

[0070] The phase (θTX1) of the transmitted signal (WT1) at timing (T12) is determined by the phase (θTIF1) of the intermediate frequency signal (WTIF1) and the phase (θTLO1) of the frequency conversion signal (WTLO). Then, the phase (θTX2) of the transmitted signal (WT2) at timing (T32) is determined by the phase (θTIF2) of the intermediate frequency signal (WTIF2) and the phase (θTLO2) of the frequency conversion signal (WTLO).

[0071] If the frequency conversion performed by the frequency conversion unit (FC) 1224 is, for example, frequency upconversion, then θTX1 is determined by the sum of θTIF1 and θTLO1, and θTX2 is determined by the sum of θTIF2 and θTLO2.

[0072] The difference between θTLO1 and θTLO2 (θTLO1-θTLO2) can be estimated from D3 and the frequency of the frequency conversion signal (WTLO). D3 can be adjusted during the process of generating the digital signal with the DSP1111. From the above, adjustment of (θTX1-θTX2) can be achieved.

[0073] According to this modified version, timing adjustment between the frequency conversion signal (WTLO), which is a high-frequency analog signal, and the transmission signal (WT) becomes unnecessary, which reduces design difficulty and lowers costs.

[0074] The operation of the demodulation unit 122 will be explained using Figure 12. Figure 12 is a waveform diagram showing the operation of the demodulation unit shown in Figure 9.

[0075] The received signal (WR1) is the signal obtained when one of the modulated signals included in the transmitted signal (WT) reaches the receiving device 120 via the object being measured 40. The received signal (WR2) is the signal obtained when one of the modulated signals included in the transmitted signal (WT) reaches the receiving device 120 via the object being measured 40.

[0076] Timing (T21) is the timing at which the output of the unmodulated signal of the received signal (WR1) begins. Timing (T22) is the timing at which the output of the modulated signal of the received signal (WR1) begins. The phase of the received signal (WR1) at timing (T22) is θRX1.

[0077] Timing (T41) is the timing at which the output of the unmodulated signal of the received signal (WR2) begins. Timing (T42) is the timing at which the output of the modulated signal of the received signal (WR2) begins. The phase of the received signal (WR2) at timing (T42) is θRX2. Here, the time difference between timing (T22) and timing (T42) is D4.

[0078] The frequency conversion signal (WRLO) is the signal output by the local oscillator (LO) 1223. The phase of the frequency conversion signal (WRLO) at timing (T22) is θRLO1. The phase of the frequency conversion signal (WRLO) at timing (T42) is θRLO2.

[0079] The intermediate frequency signal (WRIF1) is one of the modulated signals included in the intermediate frequency signal (WRIF), and is the frequency-converted signal obtained by frequency conversion of the received signal (WR1) by the frequency conversion unit (FC) 1224. The phase of the intermediate frequency signal (WRIF1) at timing (T22) is θRIF1.

[0080] The intermediate frequency signal (WRIF2) is one of the modulated signals included in the intermediate frequency signal (WRIF), and is the converted frequency signal obtained by frequency conversion of the received signal (WR2) by the frequency conversion unit (FC) 1224. The phase of the intermediate frequency signal (WRIF2) at timing (T42) is θRIF2.

[0081] The receiving device 120 estimates the frequency characteristics of the object to be measured 40 from the difference between θRX1 and θRX2 (θRX1-θRX2).

[0082] The phase (θRIF1) of the intermediate frequency signal (WRIF1) at timing (T22) is determined by the phase (θRX1) of the received signal (WR1) and the phase (θRLO1) of the frequency conversion signal (WRLO). Then, the phase (θRIF2) of the intermediate frequency signal (WRIF2) at timing (T42) is determined by the phase (θRX2) of the received signal (WR2) and the phase (θRLO2) of the frequency conversion signal (WRLO).

[0083] If the frequency conversion performed by the frequency conversion unit (FC) 1224 is, for example, a frequency down-conversion, then θRIF1 is determined by the difference between θRX1 and θRLO1, and θRIF2 is determined by the difference between θRX2 and θRLO2.

[0084] The difference between θRLO1 and θRLO (θRLO1-θRLO) can be estimated from D4 and the frequency of the frequency conversion signal (WRLO). D4 can be estimated based on the digital signal using the DSP1221. By following the above procedure, it is possible to estimate (θRX1-θRX2) without adjusting the timing of the high-frequency analog signal.

[0085] This makes it possible to measure a physical quantity by measuring the difference in frequency phase characteristics between two different frequencies, using a predetermined (θTX1-θTX2) and (θRX1-θRX2) estimated by the receiving device 120.

[0086] The effects of the fourth modified example will be explained. Since the electrical or acoustic frequency characteristics change depending on the object being measured, high frequencies such as those used in the UWB band may be suitable. The case in which the modulation signal generation unit 111 modulates and transmits a single carrier wave (comparative example) will be explained using Figures 13 and 14. Figure 13 is a waveform diagram showing the operation of the modulation signal generation unit in the comparative example of the fourth modified example. Figure 14 is a waveform diagram showing the operation of the demodulation unit in the comparative example of the fourth modified example.

[0087] As shown in Figure 13, the phase (θTX) of the transmitted signal (WT) at the modulation start timing (T12) is determined by the phase (θTIF) of the intermediate frequency signal (WTIF) and the phase (θTLO) of the frequency conversion signal (WTLO) at timing (T12).

[0088] When the frequency conversion performed by the frequency conversion unit (FC) 1114 is frequency upconversion, it is determined by the sum of θTIF and θTLO. Therefore, in order to improve the accuracy of θTX, it is necessary to adjust the timing between the intermediate frequency signal (WTIF) and the frequency conversion signal (WTLO).

[0089] For example, if the frequency conversion signal (WTLO) is an 8GHz sine wave used in the UWB band, then a time precision of 0.347 ps (= 1 / (8GHz) / 360) is required to align the phase with a degree of accuracy. Achieving this requires a highly precise design, which can increase costs.

[0090] As shown in Figure 14, the phase (θRIF) of the intermediate frequency signal (WRIF) at the modulation start timing (T22) is determined by the phase (θRX) of the transmitted signal (WR) and the phase (θRLO) of the frequency conversion signal (WRLO) at timing (T22).

[0091] To accurately measure the difference between θRX and θRLO, the precision of θRLO is crucial. However, similar to transmitters, high-precision phase adjustment requires a time-accurate design, which can increase costs.

[0092] As described above, in the fourth modification, timing adjustment between the intermediate frequency signal (WTIF) and the frequency conversion signal (WTLO) is unnecessary.

[0093] In the fourth modified example, the semiconductor device 10 calculates the phase change using the phase of the modulation start timing when switching from the unmodulated period (UMP) to the modulated period (MP). Similar to the first modified example, the phase change may be calculated using the phase of the modulation end timing when switching from the modulated period (MP) to the unmodulated period (UMP). Also, similar to the second modified example, the phase change may be calculated using the phase of a predetermined time-shifted timing from the modulation start timing when switching from the unmodulated period (UMP) to the modulated period (MP). Also, similar to the third modified example, the phase change may be calculated using the phase of a predetermined time-shifted timing from the modulation end timing when switching from the modulated period (MP) to the unmodulated period (UMP).

[0094] The disclosure made by the Discloser has been described in detail based on embodiments, but it goes without saying that the disclosure is not limited to the above embodiments and can be modified in various ways.

[0095] For example, if the frequency phase characteristics of the reflection or transmission characteristics of sound waves change due to changes in the moisture content of the object being measured, the moisture content may be measured non-contact using sound waves. In this case, the transmitting antenna of the embodiment is replaced with a speaker, and the receiving antenna is replaced with a microphone.

[0096] Furthermore, if the frequency-phase characteristics of the reflected radio waves or the frequency-phase characteristics of the reflection or transmission characteristics of sound waves change due to changes in physical quantities other than the moisture content of the object being measured, those physical quantities may also be measured. [Explanation of Symbols]

[0097] 10. Semiconductor equipment 20... Antenna 30... Antenna 40.. Object to be measured 110...Transmitter 120... Receiving device

Claims

1. A transmitting device that modulates a carrier wave with a modulation signal and radiates a transmission signal generated from an antenna towards an object to be measured, A receiving device that receives the received signal, which has passed through the object to be measured, via an antenna and demodulates it to generate a demodulated signal, and processes the demodulated signal, Equipped with, The transmitting device is configured to start modulation at a first phase, The receiving device is, The physical quantities corresponding to the first phase and phase change amount are stored in advance. Based on the waveform of the demodulated signal, the modulation start timing at which the received signal switches from the unmodulated period to the modulated period is estimated. The second phase, which is the phase at the modulation start timing, is calculated. Based on the stored first phase, the amount of change to the second phase is calculated. A semiconductor device configured to determine a physical quantity corresponding to a phase change based on a physical quantity corresponding to the phase change stored in memory.

2. In the semiconductor device according to claim 1, The object to be measured is a semiconductor device composed of metamaterials.

3. In the semiconductor device according to claim 2, The object to be measured is a semiconductor device formed by periodically arranging conductive patterns on one side of a printed circuit board in an array-like manner.

4. In the semiconductor device according to claim 1, The aforementioned physical quantity is the amount of water in a semiconductor device.

5. The semiconductor device according to claim 1, A first antenna connected to the aforementioned transmitting device, The object to be measured from which the transmission signal is radiated from the first antenna, A second antenna connected to the aforementioned receiving device, A physical quantity measuring device equipped with the following features.

6. A transmitting device that modulates a carrier wave with a modulation signal and radiates a transmission signal generated from an antenna towards an object to be measured, A receiving device that receives the received signal, which has passed through the object to be measured, via an antenna and demodulates it to generate a demodulated signal, and processes the demodulated signal, Equipped with, The transmitting device is configured to terminate modulation at the first phase, The receiving device is, The physical quantities corresponding to the first phase and phase change amount are stored in advance. Based on the waveform of the demodulated signal, the modulation termination timing at which the received signal switches from the modulated period to the unmodulated period is estimated. A second phase, which is the phase at the modulation termination timing, is calculated. Based on the stored first phase, the amount of change to the second phase is calculated. A semiconductor device configured to determine a physical quantity corresponding to a phase change based on a physical quantity corresponding to the phase change stored in memory.

7. A transmitting device that modulates a carrier wave with a modulation signal and radiates a transmission signal generated from an antenna towards an object to be measured, A receiving device that receives the received signal, which has passed through the object to be measured, via an antenna and demodulates it to generate a demodulated signal, and processes the demodulated signal, Equipped with, The transmitting device is configured to modulate so that it reaches a first phase at a timing that is a first time delay from the start of modulation. The receiving device is, The first time and the physical quantities corresponding to the first phase and phase change are stored in advance. Based on the waveform of the demodulated signal, the first time-shifted timing from the modulation start timing at which the received signal switches from the unmodulated period to the modulated period is estimated. The second phase, which is the phase at the first time shift from the modulation start timing, is calculated. Based on the stored first phase, the amount of change to the second phase is calculated. A semiconductor device configured to determine a physical quantity corresponding to a phase change based on a physical quantity corresponding to the phase change stored in memory.

8. A transmitting device that modulates a carrier wave with a modulation signal and radiates a transmission signal generated from an antenna towards an object to be measured, A receiving device that receives the received signal, which has passed through the object to be measured, via an antenna and demodulates it to generate a demodulated signal, and processes the demodulated signal, Equipped with, The transmitting device is configured to modulate so that it reaches a first phase at a timing that is first time-shifted from the end of modulation. The receiving device is, The first time and the physical quantities corresponding to the first phase and phase change are stored in advance. Based on the waveform of the demodulated signal, the first time-shifted timing is estimated from the modulation end timing at which the received signal switches from the modulation period to the unmodulated period. The second phase, which is the phase at the first time shifted from the modulation termination timing, is calculated. Based on the stored first phase, the amount of change to the second phase is calculated. A semiconductor device configured to determine a physical quantity corresponding to a phase change based on a physical quantity corresponding to the phase change stored in memory.

9. A transmitting device that radiates a first transmission signal, generated by modulating a carrier wave with a first frequency using a first modulation signal, and a second transmission signal, generated by modulating a carrier wave with a second frequency using a second modulation signal, from an antenna towards an object to be measured. A receiving device that generates a first demodulated signal by receiving and demodulating a first received signal that has passed through the object to be measured with an antenna, and generates a second demodulated signal by receiving and demodulating a second received signal that has passed through the object to be measured with an antenna, and performs processing on the first demodulated signal and the second demodulated signal. Equipped with, The transmitting device is configured to begin modulation at a first phase of a carrier wave whose carrier frequency is the first frequency, and to begin modulation at a second phase of a carrier wave whose carrier frequency is the second frequency. The receiving device is, The difference between the first phase and the second phase, and the physical quantity corresponding to the phase change amount are stored in advance. Based on the waveform of the demodulated signal, a first modulation start timing is estimated at which the first received signal switches from an unmodulated period to a modulated period, and a second modulation start timing is estimated at which the second received signal switches from an unmodulated period to a modulated period. The third phase, which is the phase at the first modulation start timing, is calculated. The fourth phase, which is the phase at the second modulation start timing, is calculated. Based on the stored difference between the first phase and the second phase, the amount of change in the difference between the third phase and the fourth phase is calculated. A semiconductor device configured to determine a physical quantity corresponding to a phase change based on a physical quantity corresponding to the phase change stored in memory.

10. A transmitting device that radiates a first transmission signal, generated by modulating a carrier wave with a first frequency using a first modulation signal, and a second transmission signal, generated by modulating a carrier wave with a second frequency using a second modulation signal, from an antenna towards an object to be measured. A receiving device that generates a first demodulated signal by receiving and demodulating a first received signal that has passed through the object to be measured with an antenna, and generates a second demodulated signal by receiving and demodulating a second received signal that has passed through the object to be measured with an antenna, and performs processing on the first demodulated signal and the second demodulated signal. Equipped with, The transmitting device is configured to terminate modulation at the first phase of a carrier wave whose carrier frequency is the first frequency, and to terminate modulation at the second phase of a carrier wave whose carrier frequency is the second frequency. The receiving device is, The difference between the first phase and the second phase, and the physical quantity corresponding to the phase change amount are stored in advance. Based on the waveform of the demodulated signal, a first modulation termination timing is estimated at which the first received signal switches from the modulated period to the unmodulated period, and a second modulation termination timing is estimated at which the second received signal switches from the modulated period to the unmodulated period. The third phase, which is the phase at the first modulation termination timing, is calculated. The fourth phase, which is the phase at the second modulation termination timing, is calculated. Based on the stored difference between the first phase and the second phase, the amount of change in the difference between the third phase and the fourth phase is calculated. A semiconductor device configured to determine a physical quantity corresponding to a phase change based on a physical quantity corresponding to the phase change stored in memory.

11. A transmitting device that radiates a first transmission signal, generated by modulating a carrier wave with a first frequency using a first modulation signal, and a second transmission signal, generated by modulating a carrier wave with a second frequency using a second modulation signal, from an antenna towards an object to be measured. A receiving device that generates a first demodulated signal by receiving and demodulating a first received signal that has passed through the object to be measured with an antenna, and generates a second demodulated signal by receiving and demodulating a second received signal that has passed through the object to be measured with an antenna, and performs processing on the first demodulated signal and the second demodulated signal. Equipped with, The transmitting device is configured to modulate a carrier wave with the first frequency as the carrier frequency so that it has a first phase at a timing that is first time-shifted from the start of modulation, and to modulate a carrier wave with the second frequency as the carrier frequency so that it has a second phase at a timing that is second time-shifted from the start of modulation. The receiving device is, The first time, the second time, the difference between the first phase and the second phase, and the physical quantity corresponding to the phase change are stored in advance. Based on the waveform of the demodulated signal, the first time-shifted timing from the first modulation start timing, in which the first received signal switches from the unmodulated period to the modulated period, and the second time-shifted timing from the second modulation start timing, in which the second received signal switches from the unmodulated period to the modulated period, are estimated. A third phase is calculated, which is the phase at a timing that is first time-shifted from the first modulation start timing. A fourth phase is calculated, which is the phase at a timing that is two times shifted from the second modulation start timing. Based on the stored difference between the first phase and the second phase, the amount of change in the difference between the third phase and the fourth phase is calculated. A semiconductor device configured to determine a physical quantity corresponding to a phase change based on a physical quantity corresponding to the phase change stored in memory.

12. A transmitting device that radiates a first transmission signal, generated by modulating a carrier wave with a first frequency using a first modulation signal, and a second transmission signal, generated by modulating a carrier wave with a second frequency using a second modulation signal, from an antenna towards an object to be measured. A receiving device that generates a first demodulated signal by receiving and demodulating a first received signal that has passed through the object to be measured with an antenna, and generates a second demodulated signal by receiving and demodulating a second received signal that has passed through the object to be measured with an antenna, and performs processing on the first demodulated signal and the second demodulated signal. Equipped with, The transmitting device is configured to modulate a carrier wave with the first frequency as the carrier frequency such that it reaches a first phase at a timing that is first time-shifted from the end of modulation, and to modulate a carrier wave with the second frequency as the carrier frequency such that it reaches a second phase at a timing that is second time-shifted from the end of modulation. The receiving device is, The first time, the second time, the difference between the first phase and the second phase, and the physical quantity corresponding to the phase change are stored in advance. Based on the waveform of the demodulated signal, the first time-shifted timing from the first modulation end timing when the first received signal switches from the modulation period to the unmodulated period, and the second time-shifted timing from the second modulation end timing when the second received signal switches from the modulation period to the unmodulated period are estimated. A third phase is calculated, which is the phase at a timing that is first time-shifted from the first modulation termination timing. A fourth phase is calculated, which is the phase at a timing that is two times later than the second modulation termination timing. Based on the stored difference between the first phase and the second phase, the amount of change in the difference between the third phase and the fourth phase is calculated. A semiconductor device configured to determine a physical quantity corresponding to a phase change based on a physical quantity corresponding to the phase change stored in memory.

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