Wireless transmission system and wireless transmission method for brain-computer interface application

Abstract

The present application relates to the technical field of data transmission, and especially relates to a wireless transmission system and a wireless transmission method for brain-computer interface application. The wireless transmission system provided by the present application comprises an on-off keying transmitter, a voltage-controlled oscillator and a wideband receiving antenna. The bandwidth of the on-off keying transmitter is modulated by the voltage-controlled oscillator, and the center frequency of the on-off keying transmitter is adjusted. A plurality of on-off keying transmitters with different center frequencies are contained in a preset frequency band range to increase the transmission rate. The wireless transmission system provided by the present application simplifies the structure of the on-off keying transmitter, saves power consumption and volume. A plurality of on-off keying transmitters with a wide range of adjustable frequencies are used to realize multiple-input multiple-output multiplexing, ultra-low power consumption and high transmission rate. The impedance is reduced and the transmission efficiency is improved by using a stacked power amplifier. The dynamic frequency tracking technology is adopted to realize low error rate and high-fidelity wireless transmission.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of data transmission, and in particular to a wireless transmission system and method for brain-computer interface applications. BACKGROUND

[0002] With the rapid development of neuroscience, microelectronics, microfabrication technology, computer science and other aspects, the current brain-computer interface technology has gradually entered a period of rapid development. In order to accurately analyze the neural network mechanism behind the neuron scale of brain function, the current brain-computer interface technology is developing towards high channel, high spatiotemporal precision. However, it also brings a series of extremely challenging technical problems. One of the most obvious and key technical challenges is the transmission and processing of a large amount of real-time data generated by the brain-computer interface with ultra-high channel and high spatiotemporal precision. Combined with the requirements of miniaturization, low power consumption and wireless implantation in brain-computer interface applications, this challenge is even more severe.

[0003] For example, for a system with 10240 channels, a sampling frequency of 30kSps, and a precision of 16b, the data stream generated will reach also 5Gbps. Even through a high compression ratio of 20:1 signal compression, we will face a constant wireless data flow of about 250Mbps.

[0004] Current wireless transmission technologies include Wi-Fi, 5G, UWB, Bluetooth, infrared, etc. Among them, only Wi-Fi, 5G and UWB can achieve this transmission rate. Wi-Fi technology is currently the main service technology for wireless local area networks. The latest 802.11ax (Wi-Fi 6) can theoretically reach a transmission rate of 2.3Gbps. The actual transmission rate is limited by the operator and is generally 100-500Mbps. The transmission distance covered by a single Wi-Fi router is about 10m or less, which basically meets the requirements of brain-computer interface data transmission rate and transmission distance. However, it uses complex and highly linear modulation and coding techniques such as OFDM, which has very high system complexity, volume, and power consumption. For example, the power consumption of an 802.11ax transmitter is about 6W, and the volume is generally greater than a few cubic centimeters. Although this technology has been used by some scholars in recent years for large-volume extracorporeal wireless brain-computer interface devices, such as in 2015, Fernandezleon et al. used improved 802.11n Wi-Fi technology to wirelessly transmit 96-channel high-precision electroencephalogram signals, with a transmission rate of 24Mbps and a transmission distance of several meters. However, the high power consumption and large volume of current Wi-Fi make it difficult to further apply to fully implanted new-generation brain-computer interfaces.

[0005] Although 5G or 4G LTE technology can basically meet the requirements of transmission rate and transmission distance, they have the same problems as Wi-Fi, such as the power consumption of a single 5G transmitter is about 5W, the power consumption of a single 4G LTE transmitter is about 4W, and the volume of each is larger than several cubic centimeters, so they are also difficult to be used in the new generation of brain-computer interface.

[0006] Although UWB has proved in theory and some prototypes that its transmission bandwidth and power consumption meet the requirements of the new generation of wireless brain-computer interface data transmission, and in recent years there have been many researches using UWB as a wireless low-power transmission method, but in actual application, it is difficult to meet the design requirements in terms of transmission stability, complexity and difficulty of the receiving end, multiplexing capability and transcutaneous loss.

[0007] Wireless infrared transmission has low power consumption, but its transmission rate after transcutaneous is generally only 20-40Mbps, the transmission distance is generally only a few centimeters, and the directivity is very strong, so the transmitter and receiver need to be aligned and used in pairs.

[0008] Although the power consumption of Bluetooth transmission is low, it also has the disadvantage of insufficient bandwidth. When many brain-computer interface devices use Bluetooth technology for data transmission, the original high-precision brain electrical signals have to be threshold processed, only the time tag information of the nerve pulse is saved and transmitted, or only the low sampling rate local field signal is transmitted, which will greatly waste the rich information contained in the high-precision brain-computer interface original data, reduce the response speed and operation accuracy of the brain-computer interface, and thus lose the advantages of high-precision brain-computer interface technology, making it difficult to meet the needs of new generation brain-computer interface applications. SUMMARY

[0009] The purpose of the present application is to overcome the defects of the prior art and provide a wireless transmission system for brain-computer interface applications, which can realize low-power and high-transmission-rate wireless transmission.

[0010] To achieve the above purpose, the following specific technical solutions are adopted in the present application:

[0011] The wireless transmission system for brain-computer interface applications provided by the present application comprises an on-off keying transmitter, a voltage-controlled oscillator and a wideband receiving antenna. The voltage-controlled oscillator is used to modulate the bandwidth of the on-off keying transmitter and adjust the center frequency of the on-off keying transmitter, so as to accommodate a plurality of on-off keying transmitters with different center frequencies in a preset frequency band range to increase the transmission rate. The wideband receiving antenna is used to receive the signal data transmitted by the on-off keying transmitter.

[0012] Preferably, the on-off keying transmitter uses a free-running voltage-controlled oscillator to directly perform on-off keying modulation, so as to simplify the structure of the on-off keying transmitter.

[0013] Preferably, the output end of the on-off keying transmitter is stacked with two power amplifiers, which are used to reduce the output impedance of the power amplifier and improve the transmission efficiency.

[0014] Preferably, the wideband receiving antenna comprises a dynamic frequency tracking module, which is used to track the frequency of the signal data transmitted by the on-off keying transmitter in real time, so as to eliminate the carrier drift of the free-running voltage-controlled oscillator and increase the sensitivity of the receiving end to realize low error rate and high-fidelity wireless transmission.

[0015] Preferably, the wideband receiving antenna further comprises an error detection module, which is used to detect errors of the received signal data in real time through the redundancy of the multiple-input multiple-output technology, and correct and restore the errors to eliminate crosstalk.

[0016] The wireless transmission method for brain-computer interface application provided by the application uses the wireless transmission system described above, and comprises the following steps:

[0017] S1, the bandwidth of the on-off keying transmitter is modulated by the voltage-controlled oscillator, and the center frequency of the on-off keying transmitter is adjusted, a plurality of on-off keying transmitters with different center frequencies are contained in a preset frequency band range, and the transmission rate is increased;

[0018] S2, the wideband receiving antenna receives the signals transmitted by the on-off keying transmitters with different center frequencies.

[0019] Preferably, the wireless transmission method for brain-computer interface application provided by the application further comprises the following steps:

[0020] S3, the dynamic frequency tracking module in the wideband receiving antenna tracks the frequency of the signal data transmitted by the on-off keying transmitter in real time;

[0021] S4, the carrier drift of the free-running voltage-controlled oscillator is eliminated according to the result of real-time tracking, the sensitivity of the receiving end is increased, and low error rate and high-fidelity wireless transmission are realized;

[0022] S5, the error detection module in the wideband receiving antenna detects errors of the received signal data in real time, and corrects and restores the errors to eliminate crosstalk.

[0023] Preferably, in step S3, the dynamic frequency tracking module in the wideband receiving antenna tracks the frequency of the signal data transmitted by the on-off keying transmitter in real time, which comprises the following steps:

[0024] S31, the signal received by the wideband receiving antenna is converted into a slow-varying voltage signal by the receiving power identification module after passing through the radio frequency mixer, and the power of the mixed intermediate frequency signal is converted into a slow-varying voltage signal;

[0025] S32, converting the voltage signal into a digital signal through an analog-digital converter and inputting the digital signal into a controller of the wideband receiving antenna;

[0026] S33, when the frequency of the signal data transmitted by the on-off keying transmitter changes, the voltage signal changes simultaneously to make the received signal strength indication signal decrease, and the controller automatically adjusts the radio frequency-local oscillator frequency to ensure that the received signal strength indication signal is maximized, so as to realize real-time tracking of the frequency of the signal data transmitted by the on-off keying transmitter.

[0027] Preferably, in step S4, eliminating the carrier frequency drift of the free-running voltage-controlled oscillator according to the result of the real-time tracking comprises the following steps:

[0028] S41, setting the radio frequency-local oscillator frequency of the wideband receiving antenna to be lower than the carrier frequency of the on-off keying signal, and when the carrier frequency drifts to low frequency or high frequency, the received signal strength indication signal will decrease;

[0029] S42, reducing the radio frequency-local oscillator frequency through the controller and detecting the received signal strength indication signal, if the received signal strength indication signal increases, the on-off keying carrier frequency drifts to low frequency, and the radio frequency-local oscillator frequency continues to be reduced, if the received signal strength indication signal decreases, the on-off keying carrier frequency drifts to high frequency, and the radio frequency-local oscillator frequency is increased, so as to ensure that the received signal strength indication signal received in real time is maximized, and then the carrier frequency drift of the free-running voltage-controlled oscillator is eliminated.

[0030] Preferably, in step S5, the real-time error detection of the received signal data through the error detection module in the wideband receiving antenna, and the error correction and restoration to eliminate the crosstalk comprise the following steps:

[0031] S51, receiving signals through a plurality of wideband receiving antennas respectively and performing cross comparison, when the signals received by N wideband receiving antennas are completely same in the compared data segment, it is considered that the signals received by the N wideband receiving antennas are real data, otherwise it is considered that there is transmission error code in the received signals, 2≤N≤the rated number of receiving antennas;

[0032] S52, using an error correction code to encode the received signals, detecting and correcting errors, reducing the error rate of the transmission technology, and improving the fidelity of the transmission.

[0033] Preferably, in step S52, the error correction code is a low-density parity-check code.

[0034] The present application can achieve the following technical effects:

[0035] The application simplifies the structure of the on-off keying transmitter, saves power consumption and volume; multiple on-off keying transmitters with a wide range of adjustable frequencies are used to realize multiple-input multiple-output multiplexing to achieve ultra-low power consumption and high transmission rate; a stacked power amplifier is used to reduce impedance and improve signal data transmission efficiency; dynamic frequency tracking technology is used to increase the sensitivity of the receiving end to achieve low error rate and high-fidelity wireless transmission. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 is a schematic diagram of the overall structure of a wireless transmission system for brain-computer interface applications according to an embodiment of the application.

[0037] Figure 2 is a schematic diagram of the structure of a multi-band multiple-input multiple-output multiplexing of multiple on-off keying transmitters with different center frequencies to achieve high transmission rate according to an embodiment of the application.

[0038] Figure 3 is a schematic diagram of the structure of a low-power wideband on-off keying transmitter and a stacked power amplifier according to an embodiment of the application.

[0039] Figure 4 is a schematic diagram of the flow of a wireless transmission method for brain-computer interface applications according to an embodiment of the application. DETAILED DESCRIPTION

[0040] In the following, embodiments of the application will be described with reference to the accompanying drawings. In the following description, the same modules are denoted by the same reference numerals. In the case of the same reference numerals, their names and functions are also the same. Therefore, their detailed descriptions will not be repeated.

[0041] In order to make the objectives, technical solutions and advantages of the application clearer, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the application and do not constitute a limitation on the application.

[0042] Figure 1 shows the overall structure of a wireless transmission system for brain-computer interface applications provided by an embodiment of the application, as shown in Figure 1 The wireless transmission system includes an on-off keying (OOK) transmitter, a voltage-controlled oscillator (VCO) and a wideband receiving antenna. The VCO is used to modulate the OOK transmitter and adjust the center frequency of the OOK transmitter, thereby accommodating multiple OOK transmitters with different center frequencies in the frequency band range to increase the transmission rate. The wideband receiving antenna is used to receive the signal data transmitted by the OOK transmitter.

[0043] OOK is a kind of simplest ASK signal modulation method using on-off keying, when transmitting "0", no carrier signal output, when transmitting "1", output constant frequency and amplitude carrier, compared with other transmission methods, greatly reduce the system complexity and power consumption of the transmission end.

[0044] The OOK transmitter of the embodiment uses wideband OOK technology. Traditional low-bandwidth OOK needs to use high-power circuits such as phase-locked loop (PLL) and frequency synthesizer (Synthesizer) with stable carrier frequency. According to the transmission theory, the stability requirement of carrier frequency is greatly reduced when transmitting in wideband, and the single OOK transmission bandwidth of the wideband OOK technology used in the embodiment reaches more than 50MHz, which is much larger than the change of VCO carrier frequency caused by pushing or load dragging, so a free-run VCO can be used for direct OOK modulation, without the need of PLL circuit to stabilize the carrier frequency, thereby greatly simplifying the structure of the OOK transmitter and saving a lot of power consumption and volume. The power consumption of each OOK is about 5mW, while the transmission rate reaches >50Mbps, which is about 1 / 10 of Bluetooth and about 1 / 1000 of Wi-Fi or 5G. And the transmission rate is more than 10 times of Bluetooth and comparable to Wi-Fi or 5G transmission rate.

[0045] Figure 2 The structure of the multi-band multi-input multi-output (MIMO) multiplexing of the OOK transmitter with multiple different center frequencies provided by the embodiment of the application is shown in FIG. 1, which shows that the OOK transmitter with multiple different center frequencies provided by the embodiment of the application can realize high transmission rate multi-band MIMO multiplexing. Figure 2 As shown in FIG. 2, the embodiment uses VCO as the carrier generator, so that the center frequency of the OOK transmitter can be adjusted in a large range, for example, the center frequency is adjusted in a large range >1GHz, and then the multi-band MIMO multiplexing of multiple wideband OOK can be realized, so as to realize high transmission rate >250Mbps.

[0046] Figure 3 The structure of the low-power wideband OOK transmitter and the stacked power amplifier (PA) provided by the embodiment of the application is shown in FIG. 3, which shows that the low-power wideband OOK transmitter provided by the embodiment of the application can realize low-power wideband OOK transmission. Figure 3As shown, two PA are stacked at the output end of the OOK transmitter and their outputs are connected in parallel, thereby reducing the total output impedance. For the ultra-low power PA, since its bias current is small, the output resistance is large, and the impedance of a general antenna is generally 50Ω or 75Ω, reducing the resistance at the PA end is beneficial to the impedance matching of the ultra-low power wireless transmission PA and the antenna, and it is very important to improve the transmission efficiency of the PA. The stacked PA technology provided in the embodiment can reduce the PA impedance by 2 times under the same power consumption, thereby improving the PA efficiency. Because each PA has an equivalent output resistance Ro, when one PA is connected on each side of the output interface, the output resistance changes from the original output resistance Ro of one PA to the parallel connection of two output resistances, that is, Ro / / Ro=1 / 2Ro, which is equivalent to reducing the equivalent output resistance to 1 / 2 of the original.

[0047] Figure 4 The flow of the wireless transmission method for brain-computer interface application provided by the embodiment of the application is shown in the figure. Figure 4 As shown, the wireless transmission method comprises the following steps:

[0048] S1, the bandwidth of the on / off key transmitter is modulated by the voltage-controlled oscillator, and the center frequency of the on / off key transmitter is adjusted, a plurality of on / off key transmitters with different center frequencies are included in the preset frequency band range, so as to increase the transmission rate.

[0049] S2, the signals transmitted by the on / off key transmitters with different center frequencies are received by the wideband receiving antenna.

[0050] The preferred embodiment of the application further comprises the following steps:

[0051] S3, the frequency of the signal data transmitted by the on / off key transmitter is tracked in real time by the dynamic frequency tracking module in the wideband receiving antenna.

[0052] The embodiment adopts a dynamic frequency tracking method at the receiving end, and tracks the carrier frequency of the OOK signal in real time through a frequency tracking module to eliminate the carrier drift of the free-run VCO at the transmitting end, lock a more accurate local oscillator (LO) frequency in real time, and thus increase the sensitivity of the receiving end and realize low error rate and high-fidelity wireless transmission. For the application of the wireless brain-computer interface technology, the power consumption is not as strict as the transmitting end at the receiving end, and the frequency tracking module is added at the receiving end to track the frequency. The specific implementation method is as follows: a received signal strength indicator module (RSSI) is connected in the signal path after the RF mixer at the receiving end, the power of the mixed IF signal is converted into a slowly changing voltage signal, and then the signal is converted into a digital signal by an analog-digital converter and input to the controller of the receiver. Since the RF-LO frequency at the receiving end is a stable frequency, when the carrier frequency of the free-run OOK drifts, the intensity of the IF signal converted from the received RF signal after the RF-Mixer will change, and this change is reflected by the change of the voltage signal output by the received signal strength indicator (RSSI). After the receiving end controller detects that the RSSI signal becomes smaller, the RF-LO frequency control is automatically adjusted to automatically track the carrier frequency of the OOK, so as to maximize the RSSI signal and realize real-time tracking of the drifting OOK carrier frequency.

[0053] S4, according to the result of real-time tracking, eliminate the carrier drift of the free-run voltage-controlled oscillator, increase the sensitivity of the receiving end to realize low error rate and high-fidelity wireless transmission;

[0054] OOK carrier frequency offset to low or high frequency can cause signal strength to be smaller. To control the RF-LO frequency to change in the opposite direction to offset this drift, it is necessary to determine where the carrier is drifting. Generally, the frequency of the receiver RF-LO is set on one side of the OOK carrier frequency, such as the left side (i.e. lower than the OOK carrier frequency). However, when the carrier frequency drifts to low or high frequency, the RSSI signal will be smaller. Here we control the controller to first reduce the RF-LO frequency, while monitoring the RSSI signal. If this control causes the RSSI signal to become larger, it means that the direction of changing the frequency is correct, that is, the OOK carrier frequency has indeed drifted to low frequency, and the controller continues to lower the RF-LO frequency. If the simultaneously detected RSSI signal becomes lower, it means that the direction of adjusting the RF-LO frequency is wrong, and the OOK carrier is actually drifting to high frequency, so the next step of the controller should increase the RF-LO frequency. Finally, ensure that the real-time received RSSI signal output is maximum, that is, the maximum received signal strength. In this way, real-time tracking of the carrier frequency can be achieved, a more accurate LO frequency can be locked, the transmission error rate caused by carrier drift can be reduced, and high-fidelity transmission can be achieved.

[0055] S5, real-time error detection of the received signal data is performed by an error detection module in the wideband receiving antenna, and error correction and restoration are performed to eliminate crosstalk;

[0056] Using MIMO technology, while multiplying the bandwidth, multiple receiving antennas are used to simultaneously receive the transmission data of the transmission end, each receiving antenna will generate a received signal, and through its redundancy, real-time cross comparison of the received signal is performed. When the signals of N receiving antennas (2≤N≤maximum number of receiving antennas, which can be determined by the user) are completely the same in the comparison data segment (such as 1024 bits), it is determined that the data received by the N antennas is real data, which can be uploaded to subsequent data transmission; otherwise, it is considered that there is transmission error in this segment of data. We will realize data error detection and error correction by encoding the data. Whether to have error detection or error correction capability will be determined by the encoding method we use. For example, we use simple 8b / 10b encoding, we will only have error detection capability, but when we use encoding with error correction capability, such as low-density parity-check code (LDPC code), we can correct the detected errors to restore the original real data. Finally, the error rate of our transmission technology is greatly reduced, and the fidelity of transmission is improved.

[0057] In the description of the specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, different embodiments or examples described in the specification and the features of different embodiments or examples can be combined and combined by those skilled in the art without contradiction.

[0058] Although the embodiments of the present application have been shown and described above, it is understood that the above-described embodiments are exemplary and are not to be construed as limiting the present application, and those skilled in the art can make changes, modifications, replacements and variations to the above-described embodiments within the scope of the present application.

[0059] The above specific embodiments of the present application do not constitute a limitation on the scope of protection of the present application. Any various other corresponding changes and modifications made in accordance with the technical concept of the present application shall be included in the scope of protection of the claims of the present application.

Claims

1. A wireless transmission system for brain-machine interface applications, characterized by, The system comprises an on-off keying transmitter, a voltage-controlled oscillator for modulating the bandwidth of the on-off keying transmitter and adjusting the center frequency of the on-off keying transmitter, thereby accommodating a plurality of on-off keying transmitters with different center frequencies within a preset frequency band range to increase the transmission rate, and a wideband receiving antenna for receiving signal data transmitted by the on-off keying transmitters.

2. The wireless transmission system for brain-machine interface application according to claim 1, wherein, The on-off keying transmitter directly performs on-off keying modulation using a free-running voltage-controlled oscillator to simplify the structure of the on-off keying transmitter.

3. The wireless transmission system for brain-machine interface application according to claim 1, wherein, Two power amplifiers are stacked at the output end of the on-off keying transmitter to reduce the output impedance of the power amplifiers and improve the transmission efficiency.

4. The wireless transmission system for brain-machine interface application according to claim 2, wherein, The wideband receiving antenna comprises a dynamic frequency tracking module for tracking the frequency of the signal data transmitted by the on-off keying transmitter in real time to eliminate the carrier drift of the free-running voltage-controlled oscillator, increase the sensitivity of the receiving end, and achieve low error rate and high-fidelity wireless transmission.

5. The wireless transmission system for brain-machine interface application according to claim 1, wherein, The wideband receiving antenna further comprises an error detection module for performing real-time error detection on the received signal data based on the redundancy of the multiple-input multiple-output technology, and performing error correction and restoration to eliminate crosstalk.

6. A wireless transmission method for brain-machine interface applications, characterized in that, The wireless transmission system according to any one of claims 1-5 comprises the following steps: S1, modulating the bandwidth of the on-off keying transmitter and adjusting the center frequency of the on-off keying transmitter by the voltage-controlled oscillator to accommodate a plurality of on-off keying transmitters with different center frequencies within a preset frequency band range to increase the transmission rate; S2, receiving the signals transmitted by the on-off keying transmitters with different center frequencies by the wideband receiving antenna.

7. The wireless transmission method for brain-machine interface application according to claim 6, wherein, The system further comprises the following steps: S3, tracking the frequency of the signal data transmitted by the on-off keying transmitter in real time by the dynamic frequency tracking module in the wideband receiving antenna; S4, eliminating the carrier drift of the free-running voltage-controlled oscillator based on the tracking result to increase the sensitivity of the receiving end and achieve low error rate and high-fidelity wireless transmission; S5, performing real-time error detection on the received signal data by the error detection module in the wideband receiving antenna, and performing error correction and restoration to eliminate crosstalk.

8. The wireless transmission method for brain-computer interface application according to claim 7, wherein, In the step S3, tracking the frequency of the signal data transmitted by the on-off keying transmitter in real time by the dynamic frequency tracking module in the wideband receiving antenna comprises the following steps: S31, the signal received by the wideband receiving antenna passes through a radio frequency mixer and then passes through a received power identification module, and the power of the mixed intermediate frequency signal is converted into a slowly varying voltage signal; S32, the voltage signal is converted into a digital signal by an analog-to-digital converter and input to the controller of the wideband receiving antenna; S33, when the frequency of the signal data transmitted by the on-off keying transmitter changes, the voltage signal also changes to reduce the received signal strength indication signal, and the controller automatically adjusts the radio frequency-local oscillator frequency to maximize the received signal strength indication signal to achieve real-time tracking of the frequency of the signal data transmitted by the on-off keying transmitter.

9. The wireless transmission method for brain-computer interface application according to claim 7, wherein, The step S4, according to the result of real-time tracking, eliminating the carrier drift of the free-running voltage-controlled oscillator includes the following steps: S41, set the radio frequency-local oscillator frequency of the wideband receiving antenna to be lower than the carrier frequency of the on / off keying signal, when the carrier frequency drifts to low frequency or high frequency, the received signal strength indication signal will decrease; S42, through the controller, reduce the radio frequency-local oscillator frequency and detect the received signal strength indication signal, if the received signal strength indication signal increases, the on / off keying carrier frequency drifts to low frequency, continue to reduce the radio frequency-local oscillator frequency; if the received signal strength indication signal decreases, the on / off keying carrier frequency drifts to high frequency, increase the radio frequency-local oscillator frequency, to ensure that the real-time received received signal strength indication signal is maximum, and then eliminate the carrier drift of the free-running voltage-controlled oscillator.

10. The wireless transmission method for brain-machine interface application according to claim 7, wherein, The step S5, through the error detection module in the wideband receiving antenna, real-time error detection is carried out on the received signal data, and error correction and restoration are carried out to eliminate crosstalk, including the following steps: S51, through a plurality of wideband receiving antennas, respectively receive signals and cross compare, when N wideband receiving antennas receive signals that are completely same in the compared data segment, it is considered that the N wideband receiving antennas receive the real data, otherwise it is considered that there is transmission error code in the received signal, 2≤N≤rated receiving antenna number; S52, using the encoding with error correction capability to encode the received signal, detecting and correcting errors, reducing the error rate of transmission technology and improving the fidelity of transmission.

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