CN103023522A - Ultra-low power consumption awakening receiver of wireless node of internet of things and short-distance wireless internet - Google Patents

Abstract

The invention relates to an ultra-low power consumption wake-up receiver for Internet of Things and short-distance wireless interconnected wireless nodes, comprising: a radio frequency signal matching network for realizing impedance matching between a front-end amplifier and an antenna; a front-end amplifier for amplifying signals; The network detector is used to detect the amplitude envelope of the signal and convert the signal into a differential pulse signal; the limiting amplifier is used to amplify the differential pulse signal; the first comparator is used to convert the input differential pulse signal into a single-ended pulse signal; the integral The device is used to integrate the single-ended pulse signal; the second comparator is used to compare the integrated voltage signal with the reference voltage signal; the edge trigger wakes up the node chip to enter the working mode according to the comparison result of the second comparator. The invention performs external remote control on wireless network nodes to make them conform to network scheduling, or is used to control the working status of short-distance wireless interconnection and information transmission nodes.

Description

Ultra-low power wake-up receiver for IoT and short-range wireless interconnected wireless nodes

technical field

The invention relates to the technical field of low power consumption of the wireless communication of the Internet of Things, in particular to an ultra-low power consumption wake-up receiver used for the wireless nodes of the Internet of Things and short-distance wireless interconnection.

Background technique

IoT technology will be widely used in all aspects of economic life and national security in the foreseeable future, and will increasingly affect economic development (such as in finance, logistics, commerce, etc.) and social life and national security (such as disasters) monitoring, early warning, etc.). Compared with the convenient wireless interconnection technology, the power consumption of the node circuit and the whole system will become more and more obvious constraints for its wide application. For a large number of scattered IoT nodes, using power line power supply is obviously an unrealistic and inappropriate solution. However, with battery power supply, frequent replacement of batteries will bring great inconvenience to the long-term stable operation of the system, and the cost and price are also very huge or even unbearable. In some specific applications, such as implanted nodes in the human body, frequent replacement of batteries not only causes great pain to the monitored object, but also brings great difficulties to practical applications. In battery-powered mobile devices, low power consumption and high energy efficiency technology is one of the technologies to improve system performance, and in IoT technology, extremely low power consumption and high energy efficiency technology will be the key to determine the practicality of IoT Core Technology. It is foreseeable that the power consumption and energy efficiency of node circuits will be the key factors restricting the widespread practical application of the Internet of Things. Power consumption issues and energy efficiency are bottlenecks for the widespread adoption of IoT technologies with a large number of dispersed nodes that rely on wireless interconnection technologies.

Contents of the invention

The technical problem to be solved by the present invention is to provide an ultra-low power consumption wake-up receiver for the Internet of Things and short-distance wireless interconnected wireless nodes to control the wireless network nodes so that they comply with network scheduling.

The technical solution adopted by the present invention to solve the technical problem is: to provide an ultra-low power consumption wake-up receiver for Internet of Things wireless nodes and short-distance wireless interconnection, including a cascaded radio frequency signal matching network, a front-end amplifier, and an envelope detector , a limiting amplifier, a first comparator, an integrator, a second comparator and an edge trigger; the radio frequency signal matching network is used to realize impedance matching between the front-end amplifier and the antenna; the front-end amplifier is used to amplify the signal; The envelope detector is used to detect the amplitude envelope of the signal and convert the signal into a differential pulse signal; the limiting amplifier is used to amplify the differential pulse signal; the first comparator is used to convert the input differential pulse signal It is a single-ended pulse signal; the integrator is used to integrate the single-ended pulse signal; the second comparator is used to compare the integrated voltage signal with a reference voltage signal; the edge trigger is based on the second comparator The comparison result wakes up the node chip to enter the working mode.

When the amplitude of the integrated signal voltage is greater than the reference voltage of the second comparator within the specified wake-up time, the second comparator sends a signal to the edge trigger to wake up the wireless transceiver to enter the working state.

The radio frequency signal matching network is realized by using an LC matching circuit.

The edge trigger is a rising edge trigger, which stores the output high level signal.

The integrator and edge trigger are passive circuit structures.

The power consumption of the front-end amplifier is 55uW.

The power consumption of the envelope detector is 16uW.

The power consumption of the limiting amplifier is 8.6uW.

Both the power consumption of the first comparator and the second comparator are less than 3.6uW.

The modulation mode of the ultra-low power consumption wake-up receiver adopts OOK modulation, and the carrier frequency is 780MHz.

Beneficial effect

Due to the adoption of the above-mentioned technical scheme, the present invention has the following advantages and positive effects compared with the prior art: the present invention adopts a simple and practical wake-up receiving circuit with an envelope detection structure as the core, and adopts a low-power consumption design Under certain circumstances, it can greatly reduce power consumption; adopt passive integrator (Integrator) and edge trigger (Trigger) to reduce false trigger probability; under appropriate design conditions, the receiving sensitivity of the wake-up receiver circuit can reach -70dBm, Power consumption below 100uW.

Description of drawings

Fig. 1 is a schematic diagram of a wireless node of the Internet of Things with a wireless wake-up function;

FIG. 2 is a system architecture diagram of an ultra-low power consumption wireless wake-up receiver proposed by the present invention;

Fig. 3 is a schematic diagram of the PCB circuit connection of the present invention.

Detailed ways

Below in conjunction with specific embodiment, further illustrate the present invention. It should be understood that these examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the teachings of the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of the present application.

The schematic diagram of the Internet of Things, short-distance wireless interconnection and information transmission wireless nodes with wireless wake-up function is shown in Figure 1. The wake-up receiver is always in the monitoring state, and the receiving link and the transmitting link of the main chip of the node are both in a dormant state. When there is a communication demand for the designated wireless node, send a communication demand command to it, wake up the receiver to detect and receive the signal, and generate a wake-up signal through data processing, which is used to wake up the main chip and make it enter the working mode (receive or send) to communicate with other nodes. After the communication is over, due to the interruption of the wake-up signal, the main chip returns to the sleep mode, and the wake-up receiver continues to be in the monitoring state, waiting for the next communication demand.

The ultra-low power consumption wake-up receiver system architecture proposed by the present invention, which can be used for the Internet of Things, short-distance wireless interconnection and information transmission wireless nodes, is shown in Figure 2, including cascaded RF signal matching networks, front-end amplifiers, and envelope detectors , a limiting amplifier, a first comparator, an integrator, a second comparator and an edge trigger; the radio frequency signal matching network is used to realize impedance matching between the front-end amplifier and the antenna; the front-end amplifier is used to amplify the signal; The envelope detector is used to detect the amplitude envelope of the signal and convert the signal into a differential pulse signal; the limiting amplifier is used to amplify the differential pulse signal; the first comparator is used to convert the input differential pulse signal It is a single-ended pulse signal; the integrator is used to integrate the single-ended pulse signal; the second comparator is used to compare the integrated voltage signal with a reference voltage signal; the edge trigger is based on the second comparator The comparison result wakes up the node chip to enter the working mode. Fig. 3 is a PCB circuit connection diagram of the present invention.

The invention makes the node platform greatly reduce the power consumption of the node circuit, greatly prolongs the working time of the node circuit, thereby greatly reducing the cost of updating the node circuit power supply. Greatly improve the technical advantages and application scope of the Internet of Things, and reduce the cost of using the Internet of Things. From the perspective of the development of the entire wireless interconnection technology, low-power circuits will increasingly occupy an important position, so the node platform featuring low power consumption and high integration will occupy more and more applications in the wireless node circuit application of the Internet of Things status. Low-power wireless wake-up technology is a management strategy and implementation technology based on improving energy efficiency.

On the premise of low power consumption and high energy efficiency, the receiver controls wireless network nodes to make them conform to network scheduling. Each circuit module is described as follows:

The RF matching network (Matching) completes the impedance matching between the front-end amplifier (FEA) and the antenna.

The front-end amplifier (FEA) is designed for ultra-low power consumption and high voltage gain to improve receiver sensitivity.

The envelope detector (ED) is used to detect the voltage amplitude envelope of the signal and realize down-conversion, so that the frequency after frequency conversion is equal to the data rate of the OOK signal, and it is also designed for ultra-low power consumption.

The limiting amplifier is designed for ultra-low power consumption and is used to amplify the differential signal output by the detector so that it can drive the first comparator (Comparator1) behind.

The first comparator (Comparator1) is used as a pulse amplifier to amplify the differential signal output by the limiting amplifier and convert it into a single-ended signal, and it is also designed for ultra-low power consumption.

The integrator (Integrator) can be designed as a passive structure to integrate the output signal of the first comparator.

The second comparator (Comparator2) is designed for ultra-low power consumption and high precision. It determines whether to generate a wake-up signal by comparing the previous integral signal with the reference voltage signal.

The edge trigger (Trigger) is active on the rising edge, and is used to keep the wake-up signal output by the front comparator, so that it has enough time to activate the main chip.

In the present invention, the wake-up receiver is always in the monitoring state, and the energy consumed by itself must be very low (far lower than the power consumption of the transceiver link of the node chip), so as to meet the requirements of ultra-low power consumption design. The modulation method of the wake-up receiver adopts OOK modulation, the carrier frequency is 780MHz, and the data rate is less than 500kbps. The receiver of the detection structure is used to control the network nodes so that their working status conforms to the network scheduling. When the node does not need to communicate, it is in a dormant state, and when it needs to communicate, it is awakened, thereby greatly extending the service life of the node battery and improving energy utilization.

When the RF signal passes through the matching network and enters the ultra-low power front-end amplifier (FEA) with high voltage gain, the signal is amplified; the envelope detector (ED) with low power consumption and high sensitivity detects the amplitude envelope of the signal and converts it into Differential signal, realizing down-conversion (after frequency conversion, the signal becomes a pulse signal with a frequency equal to the data rate); the limiting amplifier (Limiter) amplifies the pulse signal so that it can drive the comparator circuit behind; the first comparator (Comparator1) is used as a pulse amplifier in the link, which converts the differential input signal into a single-ended pulse signal from 0V to 1.2V, and enters the integrator (Integrator); the integrated signal gradually increases with time and finally tends to saturation. When the integrated signal voltage amplitude is greater than the reference voltage of the second comparator (Comparator2) within the specified wake-up time (<500us), the second comparator (Comparator2) outputs a high level (the change process generates a rising edge); and then use the rising edge An effective edge trigger (Trigger), which stores the output high-level signal, is used to wake up the node chip to enter the working mode.

In this design, the power supply voltage is 1.2V; the power consumption of the front-end amplifier (FEA) is 55uW, and the voltage gain is greater than 30dB; the power consumption of the envelope detector (ED) and the limiting amplifier (Limiter) are 16uW and 8.6uW respectively; The power consumption of the comparator (Comparator1, Comparator2) is less than 3.6uW; the integrator (Integrator) and the edge trigger (Trigger) are passive circuit structures and do not consume energy; the total power consumption of the bias circuit of all modules is less than 12uW. The test results show that the power consumption of the wake-up receiver itself is <100uW, and the sensitivity is -70dBm when the signal-to-noise ratio is 12dB, which can correctly realize the wireless wake-up function of ultra-low power consumption.

Claims (10)

1. An ultra-low power wake-up receiver for the Internet of Things and short-distance wireless interconnected wireless nodes, characterized in that it includes a cascaded RF signal matching network, a front-end amplifier, an envelope detector, a limiting amplifier, and a first comparison device, integrator, second comparator and edge trigger; the RF signal matching network is used to realize the impedance matching between the front-end amplifier and the antenna; the front-end amplifier is used to amplify the signal; the envelope detector is used to detect Output the amplitude envelope of the signal, and convert the signal into a differential pulse signal; the limiting amplifier is used to amplify the differential pulse signal; the first comparator is used to convert the input differential pulse signal into a single-ended pulse signal; the The integrator is used to integrate the single-ended pulse signal; the second comparator is used to compare the integrated voltage signal with the reference voltage signal; the edge trigger wakes up the node chip according to the comparison result of the second comparator to enter the working mode . 2. The ultra-low power consumption wake-up receiver of the Internet of Things and short-distance wireless interconnected wireless nodes according to claim 1, wherein the integrated signal voltage amplitude is greater than the reference voltage of the second comparator within the prescribed wake-up time , the second comparator sends a signal to the edge trigger to wake up the wireless transceiver to enter the working state. 3. The ultra-low power consumption wake-up receiver for Internet of Things and short-distance wireless interconnection wireless nodes according to claim 1, characterized in that, the radio frequency signal matching network is implemented by an LC matching circuit. 4. The ultra-low power consumption wake-up receiver of the Internet of Things and short-distance wireless interconnected wireless nodes according to claim 1, wherein the edge trigger is a rising edge trigger and will detect the output of the second comparator leading edge, and store the output high-level signal. 5. The ultra-low power consumption wake-up receiver for Internet of Things and short-distance wireless interconnection wireless nodes according to claim 1, characterized in that, the integrator and the edge trigger are passive circuit structures. 6. The ultra-low power consumption wake-up receiver for Internet of Things and short-distance wireless interconnected wireless nodes according to claim 1, wherein the power consumption of the front-end amplifier is 55uW. 7. The ultra-low power consumption wake-up receiver for Internet of Things and short-distance wireless interconnected wireless nodes according to claim 1, wherein the power consumption of the envelope detector is 16uW. 8. The ultra-low power consumption wake-up receiver for Internet of Things and short-distance wireless interconnected wireless nodes according to claim 1, wherein the power consumption of the limiting amplifier is 8.6uW. 9. The ultra-low power consumption wake-up receiver for Internet of Things and short-distance wireless interconnected wireless nodes according to claim 1, wherein the power consumption of the first comparator and the second comparator are both less than 3.6uW. 10. The ultra-low power consumption wake-up receiver of the Internet of Things and short-distance wireless interconnected wireless nodes according to claim 1, wherein the modulation mode of the ultra-low power consumption wake-up receiver adopts OOK modulation, and the carrier frequency is 780MHz .

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