Multi-mode processing circuit and multi-mode control method thereof

Abstract

The present invention provides a multi-mode processing circuit and a multi-mode control method thereof. The multi-mode processing circuit includes but is not limited to a control circuit and a mixer. The control circuit is used to receive an input signal and output one of a control signal and another control signal according to the input signal. The mixer is coupled to the control circuit and is used to mix the control signal output by the control circuit with another input signal, or another control signal with the other input signal, to output an output signal. In this way, the mixer and the buffer can be integrated into a single unit, and fast mode switching can be achieved.

Description

Technical Field

[0001] The present invention relates to a multi-mode integration technology, and more particularly to a multi-mode processing circuit and a multi-mode control method thereof. Background Art

[0002] Mixers and buffers are common electronic components in communication transmitters, receivers or transceivers. It is worth noting that both mixers and buffers can receive local oscillation signals provided by local oscillators (LO). In the prior art, circuit designs use switch circuits for individual mixers and buffers to switch the use of local oscillation signals. However, the aforementioned existing circuit designs require a larger layout area, and the system as a whole consumes more power. In addition, frequent switching between mixing and buffering modes may also cause insertion loss. It can be seen that the existing circuit design integrating mixers and buffers still needs to be improved. Summary of the invention

[0003] The invention provides a multi-mode processing circuit and a multi-mode control method thereof.

[0004] The multi-mode processing circuit of the embodiment of the present invention includes but is not limited to a control circuit and a mixer. The control circuit is used to receive an input signal and output one of a control signal and another control signal according to the input signal. The mixer is coupled to the control circuit and is used to mix the control signal output by the control circuit with another input signal, or another control signal with the other input signal, to output an output signal.

[0005] On the other hand, the present invention provides a multi-mode control method, which includes but is not limited to the following steps: providing the aforementioned multi-mode processing circuit; operating in one mode according to a control signal; and operating in another different mode according to another control signal.

[0006] In order to make the above features and advantages of the present invention more clearly understood, embodiments are given below with reference to the accompanying drawings for detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 is a component module diagram of a multi-mode processing circuit according to an embodiment of the present invention.

[0008] Figure 2A is a component module diagram of a control circuit according to an embodiment of the present invention.

[0009] Figure 2B is a component module diagram of a control circuit according to another embodiment of the present invention.

[0010] Figure 3A is a component module diagram of a mixer according to an embodiment of the present invention.

[0011] Figure 3B is a component module diagram of a mixer according to another embodiment of the present invention.

[0012] Figure 4 is a component module diagram of a multi-mode processing circuit according to another embodiment of the present invention.

[0013] Figure 5 is a component module diagram of a control circuit according to an embodiment of the present invention.

[0014] Figure 6 is a component module diagram of a mixer according to another embodiment of the present invention.

[0015] Figure 7 is a flow chart of a multi-mode control method according to an embodiment of the present invention.

[0016] Figure 8 is a waveform diagram of a short pulse signal according to an embodiment of the present invention.

[0017] Fig.9A It is a waveform diagram of 2-Continuous Wave (CW) application according to an embodiment of the present invention.

[0018] Fig. 9B FIG. 4 is a diagram showing phase versus time (distance) for a 2-CW application according to an embodiment of the present invention.

[0019]

Explanation of symbols

[0020] 100, 100': Multi-mode processing circuit

[0021] 110, 110-1, 110-2, 110', 110'-1: Control circuit

[0022] 111, 117: Control switch

[0023] 113: Digital to Analog Converter

[0024] 115: Low pass filter

[0025] 130, 130-1, 130-2, 150, 150-1: Mixer

[0026] 131~135, 151~155: Switching circuit

[0027] 170: Mode determination circuit

[0028] CS1, CS2, CS3: control signals

[0029] IS1~IS5、IS1-:Input signal

[0030] OS1, OS2: Output signal

[0031] SC1, SC3: Current source

[0032] T11, T12, T21, T22: Input terminal

[0033] T13, T23: output terminal

[0034] T1~T6: Transistor

[0035] CH: Choke

[0036] VDD: power supply voltage

[0037] S710~S730: Steps

[0038] TD: Time interval

[0039] Δφ: Phase difference

[0040] φf1, φf2, φIF, -φIF: Phase DETAILED DESCRIPTION

[0041] Figure 1 is a block diagram of a multi-mode processing circuit 100 according to an embodiment of the present invention. Figure 1 The multi-mode processing circuit 100 includes but is not limited to a control circuit 110 and a mixer 130. The multi-mode processing circuit 100 can be applied to various types of communication transmitters or transceivers. For example, the multi-mode processing circuit 100 can be disposed in a radar device or a distance measuring device.

[0042] The control circuit 110 is used to receive an input signal IS1. The input signal IS1 may be an AC signal of any waveform (e.g., a sine wave, a triangle wave, or a square wave, etc.), or a DC signal of any waveform or fixed amplitude. In one embodiment, the input signal IS1 is an intermediate frequency (IF) signal to be mixed. In another embodiment, the input signal IS1 is a DC bias voltage. In another embodiment, the input signal IS1 is an encoded digital signal.

[0043] In addition, the control circuit 110 can selectively output one of the control signal CS1 and the control signal CS2 according to the input signal IS1. In one embodiment, the control circuit 110 can select to output the control signal CS1 or the control signal CS2 according to the mode selection operation. This mode selection operation may be based on a preset trigger condition (for example, a detection result related to ranging or object detection, time, etc.), or it may be based on an input operation of a user on an input device (for example, a switch, a keyboard, a touch panel, etc.). In addition, in one embodiment, the control signal CS1 is a DC signal, and the control signal CS2 is an AC signal. It is worth noting that the selection of a DC or AC signal is related to the selection of a mode, and will be described in detail in subsequent embodiments.

[0044] There are many variations of the control circuit 110 . Figure 2A is a block diagram of a control circuit 110-1 according to an embodiment of the present invention. Figure 2A The control circuit 110-1 includes a control switch 111. The input terminal T11 of the control switch 111 is used to receive the input signal IS1, the input terminal T12 thereof is used to receive the input signal IS3, and the output terminal T13 thereof is coupled to the mixer 130 and is used to selectively output one of the control signal CS1 and the control signal CS2.

[0045] In one embodiment, the input signal IS1 is an intermediate frequency signal, and the input signal IS3 is a DC bias (e.g., a power supply voltage (VDD) or other fixed voltage). The control circuit 110-1 may be further connected to a control terminal (not shown), which receives a corresponding control signal (related to the selection of the input signal IS1 or the input signal IS3) in response to the aforementioned mode selection operation, thereby selecting the input signal IS1 as the control signal CS2 output (i.e., the control signal CS2 is an intermediate frequency signal), or selecting the input signal IS3 as the control signal CS1 output (i.e., the control signal CS1 is a DC bias).

[0046] Figure 2B is a block diagram of a control circuit 110-2 according to another embodiment of the present invention. Figure 2B, the control circuit 110-2 includes a digital-to-analog converter (DAC) 113 and a low pass filter (LPF) 115. The digital-to-analog converter 113 can be implemented by an N-order (N is a positive integer greater than zero) oversampling modulator or an N-bit (N-bit) Nyquist frequency sampler. In this embodiment, the input signal IS1 is an encoded digital signal, and the digital-to-analog converter 113 outputs one of the control signal CS1 and the control signal CS2 according to the encoding content of the input signal IS1. For example, Table (1) is a comparison table of the encoding content and the output voltage of the digital-to-analog converter 113:

[0047] Table (1)

[0048] Encoded content Output 1 (Volts) Output 2 (Volts) model 00 0 1.2 buffer 01 0.33 1.0 Mix 10 0.67 0.67 No output 11 1.0 0.33 Mix

[0049] If the coding content is "00", the output signal is a DC bias of 0 or 1.2 volts (i.e., a DC control signal CS1); if the coding content is "01", the output signal is an AC signal between 0.33 and 1 volt (i.e., a control signal CS2); if the coding content is "10", the output signal is a DC bias of 0.67 volts (i.e., a DC control signal CS1); if the coding content is "11", the output signal is an AC signal between 1 and 0.33 volts (i.e., a control signal CS2). The mode items will be described in detail in the subsequent embodiments.

[0050] It should be noted that the items, their values ​​and the number of items in Table (1) may vary according to actual needs, and the embodiment of the present invention is not limited thereto. In addition, Table (1) records two output terminals, one of which can be coupled to the mixer 130 .

[0051] On the other hand, the low-pass filter 115 is coupled to the digital-to-analog converter 113 and performs a low-pass filtering process on the control signal CS1 or the control signal CS2 outputted by the digital-to-analog converter 113 to filter out noise.

[0052] In other embodiments, the control circuit 110 may also be other chips or digital circuits, and is configured to select to output only the control signal CS1 or only the control signal CS2 according to the mode selection operation.

[0053] Please refer to Figure 1 The mixer 130 is coupled to the control circuit 110, receives the control signal CS1 or the control signal CS2 output by the control circuit 110, and is used to mix the control signal CS1 with the input signal IS2, or the control signal CS2 with the input signal IS2, to output the output signal OS1.

[0054] In one embodiment, the input signal IS2 is a frequency signal or a local oscillation signal provided by an oscillator (not shown) or other signal generator. The mixer 130 can mix (up-convert) the control signal CS1 or the control signal CS2 based on the frequency signal or the local oscillation signal to form a radio frequency signal (i.e., the output signal OS1).

[0055] There are many variations of mixer 130 . Figure 3A is a block diagram of a mixer 130-1 according to an embodiment of the present invention. Figure 3A The mixer 130 - 1 includes switch circuits 131 and 133 , thereby forming an unbalanced mixer.

[0056] The switch circuit 131 includes a transistor T1. The control terminal (e.g., gate) of the transistor T1 is coupled to the output terminal of the control circuit 110 and is used to receive the control signal CS1 or the control signal CS2. The first terminal (e.g., source) of the transistor T1 is coupled to the current source SC1 (the other terminal of which is used to couple a reference voltage terminal, such as ground), and the second terminal (e.g., drain) of the transistor T1 serves as the output terminal of the switch circuit 131. The switch circuit 131 is controlled by one of the control signal CS1 and the control signal CS2 to change the conduction degree, for example, it can be turned on or off, so that one of the control signal CS1 and the control signal CS2 is output or cut off.

[0057] For example, when the control signal CS1 is at a high voltage level, the switch circuit 131 is turned on, so that the switch circuit 131 outputs the control signal CS1 to the switch circuit 133. For another example, the control signal CS2 in the form of an AC is input to the switch circuit 131, so that the conduction degree of the switch circuit 131 can be dynamically controlled, such as being turned on or off. For another example, when the control signal CS1 is at a low voltage level (i.e., the potential of the reference voltage, such as the ground potential), the switch circuit 131 is turned off, so that the switch circuit 131 has no output.

[0058] The switch circuit 133 includes a transistor T2. The control terminal (e.g., gate) of the transistor T2 is used to receive the input signal IS2, the first terminal (e.g., source) of the transistor T2 is coupled to the output terminal of the switch circuit 131, and the second terminal (e.g., drain) of the transistor T2 is used as the output terminal of the switch circuit 133. The switch circuit 133 is controlled by the input signal IS2 to change the degree of conduction, for example, it can be turned on or off, so that one of the control signal CS1 and the control signal CS2 passes or is cut off, thereby achieving a mixing effect. The switch circuit 133 can mix the control signal CS1 and the input signal IS2 output by the switch circuit 131, or the control signal CS2 and the input signal IS2 (e.g., operate in a mixing mode) to form an output signal OS1.

[0059] If the switch circuit 133 receives the control signal CS1, the carrier frequency of the output signal OS1 may be the sum of the carrier frequencies of the control signal CS1 and the input signal IS2. In one embodiment, the control signal CS1 is a DC signal, the carrier frequency of the output signal OS1 is equal to the carrier frequency of the input signal IS2, and the mixer 130 may be used as a buffer (e.g., operated in a buffer mode).

[0060] On the other hand, if the switch circuit 133 receives the control signal CS2, the carrier frequency of the output signal OS1 can be the sum of the carrier frequencies of the control signal CS2 and the input signal IS2. In one embodiment, the control signal CS2 is an AC signal with a specific periodic characteristic (e.g., a sine wave intermediate frequency signal or a signal of other waveform), and the output signal OS1 forms a radio frequency signal.

[0061] In one embodiment, the multi-mode processing circuit 100 further includes a choke CH. One end of the choke CH is coupled to the output end of the mixer 130-1 (eg, the output end of the switch circuit 133), and the other end thereof receives the power supply voltage VDD or other fixed voltage. The choke CH can be used to reduce or filter out noise interference.

[0062] Figure 3B is a block diagram of a mixer 130-2 according to another embodiment of the present invention. Figure 3B , which is different from the embodiment of the mixer 130 - 1 , is that the mixer 130 - 2 further includes a switch circuit 135 , thereby forming a single balanced mixer.

[0063] The switch circuit 135 includes a transistor T3. The control end (e.g., gate) of the transistor T3 is used to receive the input signal IS4, the first end (e.g., source) of the transistor T3 is coupled to the output end of the switch circuit 131, and the second end (e.g., drain) of the transistor T3 is used as the output end of the switch circuit 135 (which can be selectively coupled to the choke CH). The input signal IS4 can be a frequency signal or a local oscillation signal. The switch circuit 135 is controlled by the input signal IS4 to change the degree of conduction, for example, it can be turned on or off, so that one of the control signal CS1 and the control signal CS2 passes or is cut off, thereby achieving a mixing effect. The switch circuit 135 can mix the control signal CS1 and the input signal IS4, or the control signal CS2 and the input signal IS4 output by the switch circuit 131 (e.g., operate in a mixing mode) to form an output signal OS2 different from the output signal OS1.

[0064] In one embodiment, the input signal IS4 is an inverted signal of the input signal IS2. If the switch circuit 133 receives the control signal CS2 (e.g., an AC signal with a specific periodic characteristic), the carrier frequency of the output signal OS2 is the difference between the control signal CS2 and the carrier frequency of the input signal IS2. In other embodiments, the input signal IS4 may also have a different frequency from the input signal IS2.

[0065] In another embodiment, if the switch circuit 131 receives the control signal CS1 in a DC form, the mixer 130-2 can be used as a differential amplifier, that is, it can have a buffer function (eg, operate in a buffer mode), and the output signals OS1 and OS2 are related to the voltage difference between the input signals IS2 and IS4.

[0066] The above embodiments are related to a single mixer, but there are other variations of the multi-mode processing circuit 100 .

[0067] Figure 4 is a block diagram of a multi-mode processing circuit 100' according to another embodiment of the present invention. Figure 4 , which is different from the embodiment of the multi-mode processing circuit 100, is that the multi-mode processing circuit 100′ further includes another mixer 150 (coupled to the control circuit 110′), and the control circuit 110′ provides two output terminals to output one of the control signal CS1 and the control signal CS2 to the mixer 130 and the mixer 150 respectively.

[0068] There are many variations of the control circuit 110 ′. Figure 5 is a block diagram of a control circuit 110'-1 according to an embodiment of the present invention. Figure 5 , which is different from the embodiment of the control circuit 110-1, is that the control circuit 110'-1 further includes a control switch 117. The input terminal T21 of the control switch 117 is used to receive the inverted input signal IS1 (represented by the input signal IS1-), the input terminal T22 thereof is grounded, and the output terminal T23 thereof is coupled to the mixer 150 and is used to output the control signal CS1 or the control signal CS2. That is, the control circuit 110'-1 includes two output terminals T13 and T23.

[0069] Similarly, the control circuit 110'-1 may be further connected to a control terminal (not shown), which receives a corresponding control signal (related to the selection of input signals IS1 and IS1-, or input signal IS3 and the potential of a reference potential terminal, such as ground) in response to the aforementioned mode selection operation, thereby selecting input signal IS1 as the output of mixer 130 and selecting input signal IS1- as the output of mixer 150 (i.e., output control signal CS2), or selecting input signal IS3 as the output of mixer 130 and selecting mixer 150 to have no output or 0 potential (i.e., output control signal CS1).

[0070] For example, Table (2) is a comparison table of the output voltage and mode of the control circuit 110'-1:

[0071] Table (2)

[0072]

[0073] If the output terminal T23 is grounded and the output terminal T13 outputs the power supply voltage VDD (i.e., the input signal IS3, and may also be other fixed voltages), the output signal is the power supply voltage VDD (i.e., the DC control signal CS1); if the output terminal T23 outputs the input signal IS1- and the output terminal T13 outputs the input signal IS1, the output signal is the control signal CS2 (the amplitude in the AC form may be positive or negative); if the output terminals T13 and T23 output signals of the same potential, the DC control signal CS1 is output.

[0074] In another embodiment, the control circuit 110' may be as follows Figure 2B The control circuit 110 - 2 of the embodiment. Taking the comparison table in Table (1) as an example, the output terminal 1 can be coupled to the mixer 150 , and the output terminal 2 can be coupled to the mixer 130 .

[0075] on the other hand, Figure 6 FIG. 1 is a block diagram of components of mixers 130 and 150 according to another embodiment of the present invention. Figure 6 , the mixer 130 is Figure 3B The mixer 130-2 in the embodiment is taken as an example, but in other embodiments, it may be Figure 3A The mixer 130-1 or other mixers are described in detail. The other mixer 150-1 includes switch circuits 151, 153 and 155, and together with the mixer 130-2 forms a double-balanced mixer (eg, a Gilbert cell).

[0076] The switch circuit 151 includes a transistor T4. The control terminal (eg, gate) of the transistor T4 is coupled to the output terminal (eg, Figure 5The output terminal T23 of the switch circuit 151 or the output terminal 1 of Table (1) is used to receive the control signal CS1 or the control signal CS2, the first terminal (e.g., the source) of the transistor T4 is coupled to the current source SC3 (the other terminal of which is grounded), and the second terminal (e.g., the drain) of the transistor T4 serves as the output terminal of the switch circuit 151. The switch circuit 151 is controlled by one of the control signal CS1 and the control signal CS2 to be turned on or off, so that one of the control signal CS1 and the control signal CS2 is output or cut off.

[0077] The switch circuit 153 includes a transistor T5. The control end (e.g., gate) of the transistor T5 is used to receive the input signal IS5, the first end (e.g., source) of the transistor T5 is coupled to the output end of the switch circuit 151, and the second end (e.g., drain) of the transistor T5 is used as the output end of the switch circuit 153 (which can be selectively coupled to the choke CH). The switch circuit 153 is controlled by the input signal IS5 to be turned on or off, so that one of the control signal CS1 and the control signal CS2 is passed or cut off, thereby achieving a mixing effect. The switch circuit 153 can mix the control signal CS1 and the input signal IS5, or the control signal CS2 and the input signal IS5 output by the switch circuit 151 (e.g., operate in a mixing mode) to form an output signal OS2.

[0078] In one embodiment, the carrier frequency of the input signal IS5 is the same as the input signal IS2. For example, the input signal IS5 is the input signal IS2. If the switch circuit 153 receives the inverted control signal CS2 (for example, an AC signal with a specific periodic characteristic), the carrier frequency of the output signal OS2 is the difference between the carrier frequencies of the control signal CS2 and the input signal IS2 (that is, the sum of the carrier frequencies of the inverted control signal CS2 and the input signal IS5).

[0079] The switch circuit 155 includes a transistor T6. The control terminal (e.g., gate) of the transistor T6 is used to receive the input signal IS4, the first terminal (e.g., source) of the transistor T6 is coupled to the output terminal of the switch circuit 151, and the second terminal (e.g., drain) of the transistor T6 is used as the output terminal of the switch circuit 155 (which can be selectively coupled to the choke CH). The input signal IS4 can be a frequency signal or a local oscillation signal. The switch circuit 155 is controlled by the input signal IS4 to change the degree of conduction, for example, it can be turned on or off, so that one of the control signal CS1 and the control signal CS2 passes or is cut off, thereby achieving a mixing effect. The switch circuit 155 can mix the control signal CS1 and the input signal IS4, or the control signal CS2 and the input signal IS4 output by the switch circuit 151 (e.g., operate in a mixing mode) to form an output signal OS1 (assuming that the input signal IS4 is an inverted signal of the input signal IS2).

[0080] In one embodiment, if the switch circuit 151 receives the control signal CS1 in a DC form, the mixer 150 - 1 can be used as a differential amplifier, that is, it can have a buffer function (eg, operate in a buffer mode), and the output signals OS1 and OS2 are related to the voltage difference between the input signals IS4 and IS5 .

[0081] It should be noted that, in another embodiment, the mixer 150 may not include the switch circuit 155 (ie, the mixer 150 only includes the switch circuits 151 and 153), and the related description may refer to FIG. Figure 3A The description of the mixer 130 - 1 is not repeated here.

[0082] In addition, please refer to Figure 4 In one embodiment, the multi-mode processing circuit 100' further includes a mode determination circuit 170. The mode determination circuit 170 is coupled to the control circuit 110' (e.g., the control terminal of the control circuit 110'). The mode determination circuit 170 outputs a control signal CS3, and the control circuit 110' can select to output one of the control signal CS1 and the control signal CS2 based on the control signal CS3.

[0083] In one embodiment, the control signal CS3 determines whether the control circuit 110' provides one of the control signals CS1 and CS2 based on the detection result, and the detection result is detected based on the output signal OS1. Specifically, the output end of the mixer 130 can be connected to the RF front-end circuit (not shown, for example, a power amplifier (PA) and an antenna) to transmit the output signal OS1 and / or the output signal OS2. The receiver can receive the reflected signal of the output signal OS1 and / or the output signal OS2, and determine the analysis result of whether there is a moving object based on the reference distance. The mode determination circuit 170 can provide the control signal CS3 based on the analysis result. For example, a high potential of the control signal CS3 indicates that there is a moving object, and a low potential indicates that there is no moving object.

[0084] In another embodiment, the control signal CS3 may also be generated based on user input operations, time adjustment or other analysis results.

[0085] As can be seen from the above description, the mixers 130 and 150 of the present invention integrate the buffer to form a single unit, and can form a mixer and a buffer by inputting different control signals CS1 and CS2. The operation will be described in detail below. Figure 4 and Figure 6 The embodiments are mainly described in detail, but other embodiments may also be implemented.

[0086] Figure 7is a flow chart of a multi-mode control method according to an embodiment of the present invention. Figure 7 , the multi-mode processing circuit 100' operates in a mode according to the control signal CS1 (step S710). In one embodiment, the control signal CS1 is a DC signal. Figure 5 Taking the control circuit 110'-1 as an example, the output terminal T13 of the control switch 111 is connected to the input terminal T12, the output terminal T23 of the control switch 117 is connected to the input terminal T22, and this mode is the buffer mode. Alternatively, taking Table (1) and Figure 2B Taking the control circuit 110 - 2 as an example, the encoding content is “00”, and it is assumed that the power supply voltage VDD is 1.2V.

[0087] It is worth noting that please refer to Figure 6 , the voltage of the switch circuit 131 of the mixer 130-2 is the power supply voltage VDD, and the voltage of the output terminal of the switch circuit 133 is the power supply voltage VDD, so that the mixer 130-2 has no output. On the other hand, the voltage of the switch circuit 151 of the mixer 150-1 is the potential of the reference potential terminal, such as 0 volts, and the voltage of the output terminal of the switch circuit 153 is the power supply voltage VDD, so that the mixer 150-1 acts as a differential amplifier, that is, has a buffering function. In the buffering mode, the multi-mode processing circuit 100' can provide a 1-continuous wave (Continuous Wave, CW) signal (for example, the output signals OS1 and OS2 are used as radar signals), and can be used for object motion detection.

[0088] In another embodiment, if the mixer 130-2 and the mixer 150-1 receive signals with the same potential (e.g., the code content in Table (1) is "10", or the same potential in Table (2)), the differential pair formed by the switch circuits 131 and 151 subtracts the two potentials to obtain a 0 potential, and the mixer 130-2 and the mixer 150-1 both have no output (hereinafter referred to as the no-output mode).

[0089] In one embodiment, the buffer mode combined with the no-output mode can be implemented in ultra-wideband (UWB) applications. Specifically, Figure 8 is a waveform diagram of a short pulse signal according to an embodiment of the present invention. Figure 8 , the multi-mode processing circuit 100' switches to the buffer mode in the time interval TD, and switches to the non-output mode after the time interval TD ends. Assuming that the value of the time interval TD is less than a specific threshold (for example, less than or about 2 nanoseconds (ns)), the output signal OS1 and / or OS2 will form a flat spread spectrum signal on the spectrum, and can be used as a UWB application to determine the distance and position.

[0090] Please refer to Figure 7 , the multi-mode processing circuit 100' operates in another mode according to the control signal CS2 (step S730). In one embodiment, the control signal CS2 is an AC signal. Figure 5 Taking the control circuit 110'-1 as an example, the output terminal T13 of the control switch 111 is connected to the input terminal T11, and the output terminal T23 of the control switch 117 is connected to the input terminal T21, and this mode is the mixing mode. Alternatively, taking Table (1) and Figure 2B Taking the control circuit 110-2 as an example, the encoding content is "01" or "11". It is worth noting that please refer to Figure 6 The AC input signals IS1 and IS1- will dynamically change the conduction degree of the switch circuits 131 and 151, such as turning on or off the switch circuits 131 and 151, and combined with the input of the frequency signal or the local oscillation signal, the mixing function can be achieved.

[0091] In the mixing mode, the multi-mode processing circuit 100' can provide a 2-CW signal (for example, output signals OS1 and OS2 as radar signals), and can be used for distance detection of moving objects (for example, short-range narrowband distance estimation). Figure 6 For example, it is assumed that the control signal CS2 received by the mixer 130 - 2 is an intermediate frequency signal, and the control signal received by the mixer 150 - 1 is an inverted intermediate frequency signal. Fig.9A is a waveform diagram of a 2-CW application according to an embodiment of the present invention. Fig.9A , assuming that the waveforms of the output signals OS1 and OS2 are as shown in the figure. The frequency f1 of the output signal OS1 is the local oscillation signal f LO With the intermediate frequency signal f IF The sum of the carrier frequencies (i.e., f1 = f LO +f IF ), and the frequency f2 of the output signal OS2 is the local oscillation signal f LO With the inverted intermediate frequency signal f- IF The sum of the carrier frequencies (i.e., f2 = f LO -f IF ).

[0092] It is worth noting that based on Doppler frequency shift, the signal propagation distance is related to the change in phase. Assuming that the output signals OS1 and OS2 are transmitted through the RF front-end circuit, the two transmitted signals with different carrier frequencies are reflected by the moving object and received by the receiver. The phase difference between the two signals is Will be related to the relative distance of the moving object.

[0093] Fig. 9Bis a diagram showing the phase and time (distance) correspondence of a 2-CW application according to an embodiment of the present invention. Fig. 9B , Phase Corresponding to the phase of the output signal OS1 (eg, the phase of the local oscillation signal Phase with IF signal The sum of ), and the phase Corresponding to the phase of the output signal OS2 (eg, the phase of the local oscillation signal Phase with IF signal The difference, that is ). Phase difference Two-phase and The difference (i.e., ). It is worth noting that since the mixers 130 and 150 can synchronously input the local oscillation signal, an initial reference phase for synchronization between the output signal OS1 and the output signal OS2 can be provided. Since the initial reference phase can be synchronized, the phase difference The corresponding distance estimation result can also be more accurate.

[0094] In one embodiment, if the detection result (i.e., the aforementioned analysis result) of the mode based on the control signal CS1 (i.e., using 1-CW motion detection) is the presence of a moving object, the mode determination circuit 170 may generate a control signal CS3 that drives the control circuit 110 to provide the control signal CS2, and thus switch to the mode based on the control signal CS2 (i.e., using 2-CW distance detection for moving objects). On the other hand, if the detection result of the mode based on the control signal CS1 is that no moving object appears, the multi-mode processing circuit 100' maintains the current mode. Since 1-CW motion detection is more power-efficient than 2-CW distance detection, the aforementioned switching mechanism allows the multi-mode processing circuit 100' to switch to the 2-CW distance detection mode when there is a need for distance detection (e.g., the presence of a moving object), and there is no need to maintain the 2-CW distance detection at all times, thereby saving energy.

[0095] On the other hand, the mixers 130 and 150 of the embodiment of the present invention are current driven (eg Figure 3A , Figure 3B and Figure 6 ), and by changing the voltage levels of the input signals IS1 and IS1- or by changing the digital code content, a fast switching mode can be achieved.

[0096] In summary, the multi-mode processing circuit and multi-mode control method of the embodiments of the present invention integrate the buffer and the mixer. For example, the mixer and the buffer can be integrated into a single unit, thereby saving wiring area and power consumption. In addition, by inputting different control signals, mode switching can be achieved and insertion loss can be reduced. In radar applications, the embodiments of the present invention can provide detection or estimation of 1-CW, 2-CW and short pulse modes. In the case of current-driven switching, the embodiments of the present invention can achieve fast mode switching. In addition, for 2-CW distance detection, a synchronized initial reference phase can be provided, thereby improving the accuracy of distance estimation.

[0097] Although the present invention has been disclosed as above by way of embodiments, it is not intended to limit the present invention. Any person having ordinary knowledge in the technical field may make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be determined by the scope of the claims.

Claims

1. A multi-mode processing circuit, characterized in that: include: a control circuit for receiving a first input signal and outputting one of a first control signal and a second control signal according to the first input signal, wherein the first control signal is a DC signal and the second control signal is an AC signal; and a mixer, coupled to the control circuit and outputting a first output signal; in, The mixer is used to mix the second control signal output by the control circuit with a second input signal to output the first output signal; or, The mixer is used for receiving the first control signal output by the control circuit and operating in a buffer mode to output the first output signal.

2. The multi-mode processing circuit according to claim 1, characterized in that: The control circuit includes: a first control switch, including: a first input terminal, for receiving the first input signal; a second input terminal for receiving a third input signal; and an output terminal coupled to the mixer and used to output the first control signal or the second control signal, wherein The first control switch selects the first input signal to be output as the first control signal, or selects the third input signal to be output as the second control signal.

3. The multi-mode processing circuit according to claim 1, characterized in that: The control circuit comprises: A digital-to-analog converter outputs one of the first control signal and the second control signal according to the encoding content of the first input signal.

4. The multi-mode processing circuit according to claim 1, wherein: The mixer includes: a first switch circuit coupled to the control circuit and controlled by one of the first control signal and the second control signal to output or cut off one of the first control signal and the second control signal; and a second switch circuit, coupled to the first switch circuit, controlled by the second input signal, and The second switch circuit mixes the second control signal output by the first switch circuit with the second input signal to form the first output signal, or, The second switch circuit receives the first control signal output by the first switch circuit and operates in the buffer mode to form the first output signal.

5. The multi-mode processing circuit according to claim 4, characterized in that: in In response to the second switch circuit receiving the first control signal, the carrier frequency of the first output signal output by the second switch circuit is equal to the carrier frequency of the second input signal; and In response to the second switch circuit receiving the second control signal, the carrier frequency of the first output signal output by the second switch circuit is the sum of the carrier frequencies of the second control signal and the second input signal.

6. The multi-mode processing circuit according to claim 4, characterized in that: The mixer further comprises: A third switch circuit is coupled to the first switch circuit, receives a fourth input signal, is controlled by the fourth input signal, and mixes the fourth input signal according to the first control signal output by the first switch circuit, or mixes the fourth input signal according to the second control signal, to form a second output signal different from the first output signal.

7. The multi-mode processing circuit according to claim 1, characterized in that: Also includes: A second mixer is coupled to the control circuit and is used to mix the first control signal output by the control circuit with a fifth input signal, or to mix the second control signal output by the control circuit with the fifth input signal, so as to output a third output signal different from the first output signal.

8. The multi-mode processing circuit according to claim 7, characterized in that: The mixer is coupled to a first output terminal of the control circuit, the second mixer is coupled to a second output terminal of the control circuit, and the first output terminal and the second output terminal jointly output one of the first control signal and the second control signal.

9. The multi-mode processing circuit according to claim 7, characterized in that: The control circuit includes: a second control switch including: a third input terminal, for receiving the inverted first input signal; a fourth input terminal, for coupling to a reference voltage terminal; and a second output terminal coupled to the second mixer and used to output the first control signal or the second control signal, wherein The second control switch selects not to output, or selects the inverted first input signal to output as the second control signal.

10. The multi-mode processing circuit according to claim 8, characterized in that: in In response to the second mixer receiving the second control signal, The carrier frequency of the third output signal output by the second mixer is the sum of the carrier frequencies of the second control signal and the fifth input signal in an inverted form.

11. The multi-mode processing circuit according to claim 8, characterized in that: The carrier frequency of the fifth input signal is equal to the second input signal.

12. The multi-mode processing circuit according to claim 7, wherein: The second mixer comprises: a fourth switch circuit coupled to the control circuit and controlled by one of the first control signal and the second control signal to output or cut off one of the first control signal and the second control signal; a fifth switch circuit, coupled to the fourth switch circuit, controlled by the fifth input signal, and mixing the fifth input signal with the first control signal output by the fourth switch circuit, or mixing the fifth input signal with the second control signal output by the fourth switch circuit, to form the third output signal; and A sixth switch circuit is coupled to the fourth switch circuit, receives a sixth input signal, is controlled by the sixth input signal, and mixes the sixth input signal according to the first control signal output by the fourth switch circuit, or mixes the sixth input signal according to the second control signal output by the fourth switch circuit, to form a fourth output signal different from the third output signal.

13. The multi-mode processing circuit according to claim 1, wherein: Also includes: a choke coil, one end of which is coupled to the mixer output terminal, and the other end of which receives a sixth input signal; and A current source has one end coupled to the mixer and the other end coupled to a reference voltage end.

14. The multi-mode processing circuit according to claim 1, wherein: Also includes: A mode determination circuit is coupled to the control circuit and determines the control circuit to provide one of the first control signal and the second control signal according to a detection result, wherein the detection result is detected based on the first output signal.

15. A multi-mode control method, characterized in that: include: The multi-mode processing circuit as claimed in claim 1; operating in a first mode according to the first control signal; as well as The device operates in a second mode according to the second control signal, wherein the second mode is different from the first mode.

16. The multi-mode control method according to claim 15, characterized in that: The first mode is used for object motion detection.

17. The multi-mode control method according to claim 15, characterized in that: The second mode is used for distance detection of a moving object.

18. The multi-mode control method according to claim 16, characterized in that: These include: If the detection result in the first mode is that a moving object appears, the mode is switched to the second mode, wherein the second mode is used for distance detection of the moving object.

19. The multi-mode control method according to claim 15, characterized in that: The step of operating in the second mode according to the second control signal includes: Providing the third switching circuit according to claim 6 or the second mixer according to claim 7; and An initial reference phase for synchronization is provided between the first output signal and the second output signal or between the first output signal and the third output signal.

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