KR100967304B1 - Method and Apparatus for Point-to-Point Wireless Transceiver Using a Adaptive Frequency Control in FM Broadcast Band - Google Patents

Abstract

The present invention is used as a frequency or broadcast frequency not used as a broadcast frequency in any region of the FM radio broadcast frequency, but the radio transmission and reception using the frequency adaptation technology and the frequency adaptation technology to find a frequency that the broadcast output power is low to listen to the FM radio broadcast The present invention relates to a device which, more specifically, does not interfere with other radio devices that want to listen to FM radio broadcast in the FM radio broadcast frequency band, and avoids interference between radio transceivers that comply with short-range, low-power, and unlicensed radio laws. The present invention relates to a wireless transmission and reception method and apparatus for finding a frequency that can be used as a frequency of a device for one-to-one wireless transmission and reception.

In the wireless transmission / reception method using the frequency adaptation technology according to the present invention, one radio transceiver A1 and the other radio transceiver A2 perform one-to-one wireless communication, but perform communication for low power and local area in compliance with unauthorized radio regulations. A method of wireless transmission and reception using a frequency adaptation technique, the method comprising: (a) an arbitrary measurement at an arbitrary frequency shift interval (A) from a preset start frequency (S) in one radio transceiver (A1) for performing radio transmission and reception; Measuring a received electric field strength of a received frequency signal while moving by a desired frequency C; (b) setting a minimum value of the measured received electric field strength to a noise level (B); (c) measuring the received electric field strength of the received frequency signal by resetting the reception frequency to the start frequency S and then moving from the start frequency S to the frequency shift interval A; (d) When the received electric field strength measured at each frequency is smaller than the reference electric field strength which is the sum of the noise level (B) and the predetermined arbitrary electric field strength (D), the frequency having the received electric field strength is converted into a wireless transmit / receive frequency. Determining; characterized in that it comprises a.

Frequency Awareness Technology, Frequency Adaptation Technology, Radio Transceiver, Unlicensed Radio Law

Description

{Method and Apparatus for Point-to-Point Wireless Transceiver Using a Adaptive Frequency Control in FM Broadcast Band}

The present invention relates to a method and apparatus for wireless transmission and reception using a frequency adaptation technique. More particularly, the present invention relates to a frequency or broadcast frequency that is not used as a broadcast frequency among FM radio broadcast frequency bands in any region, but has low broadcast output power. The present invention relates to a wireless transmission / reception method and apparatus using a frequency adaptation technique that finds a frequency where radio broadcasting cannot be heard and uses digital information as a frequency of a device that transmits and receives digital information one-to-one.

Next Generation Network (xG Network) for efficient use of limited frequency resources is existing wireless network such as Code Division Multiple Access (CDMA), Global System for Mobile Communication (GSM), Wireless Local Area Network (WLAN), etc. Using frequency bands, frequency recognition can be used to improve the quality of wireless services by complying with existing wireless network standards such as modulation scheme, frequency used, and wireless output power, or to improve frequency utilization by performing new wireless network services. A lot of research is being done on various concepts such as Cognitive Radio or Dynamic Spectrum Access, and the only IEEE 802.22 frequency-aware technology that has been standardized by the Institute of Electrical and Electronics Engineers (IEEE). Point-to multipoint Wi with Cyclo-Stationary signals It is to implement a reless Regional Area Networks service. In addition to the next generation wireless network using the frequency recognition concept, in order to efficiently use various existing wireless networks, CORVUS (Cognitive Radio Approach for usage of Virtual Unlicensed Spectrum) and DIMSUMnet (Dynamic Intelligent Management of Spectrum for Ubiquitous) Mobile Network, etc. There are many, and unlike IEEE 802.22, all these next generation wireless networks are under standardization research.

Next-generation wireless networks using existing frequency-aware technologies that can improve frequency utilization efficiency are optimized wireless communication such as modulation scheme, frequency, and wireless output power even when the mobile terminal is moved or fixed mobile terminal. In order to select an environment, unilateral transmission or exchange of optimal wireless communication environment information and / or location information between one or both sides between the wireless terminal and the base station should be performed periodically or in any particular situation. In addition, the mobile wireless terminal and the base station must perform frequency recognition processes such as spectrum sensing, spectrum analysis, and decision of a wireless network to be used.

However, in the next generation wireless network using the frequency recognition concept, an FM radio broadcasting frequency band in which a device that does not require a network configuration by one-to-one wireless communication, for example, a computer mouse, a keyboard, a printer, etc., does not continuously change in an arbitrary region. When using a frequency that does not cause radio interference when receiving an FM radio broadcast by another person, the process of recognizing and analyzing the radio wave environment such as modulation method and wireless output power may not be required or simplified among existing frequency recognition technologies. will be.

In order to improve the efficiency of using the frequency, the service of the existing wireless network is performed through the process of recognizing, analyzing, and determining the wireless network's physical standards such as modulation scheme, frequency, and wireless output power of the existing wireless network using frequency recognition technology. Unlike next-generation wireless networks to improve quality or create new services, the present invention complies with low-power, near-field, and unlicensed radio laws, and propagates to radio-transmission services for primary users licensed for frequency use. It has been proposed for the development of a frequency adaptation method and apparatus capable of performing one-to-one wireless transmission and reception without interference, and without interference between secondary users using frequencies adapted to the surrounding radio environment.

An object of the present invention is to replace the existing process of recognition, analysis, and wireless network determination by using a radio frequency band such as FM radio band that does not change for a long time in any region. By simply measuring the received electric field strength of each frequency in the broadcasting frequency band, the frequency or broadcasting that is not used as the broadcasting frequency by distinguishing the broadcasting frequency from the surrounding area (Spectrum Hole) However, the present invention provides a frequency adaptive one-to-one wireless transmission / reception method and apparatus that comply with short-range, low-power and unlicensed radio laws by using unused frequencies with very low reception field strength.

According to the first aspect of the present invention to achieve the above object, the frequency adaptive radio transceiver of the present invention to measure the received electric field strength of individual frequencies of the FM radio frequency band at one side of the frequency adaptive radio transceiver Determine, transmit a frequency synchronization signal using the determined frequency, search for a frequency synchronization signal of the FM radio frequency band in another side of the frequency adaptive radio transceiver, and finally use it on both sides of the frequency adaptive radio transceiver It provides a method of determining the frequency to.

According to a second aspect of the present invention for achieving the above object, when one side of the frequency adaptive radio transceiver determines a frequency that can be used to find the spectrum-hole, frequency adaptive radio transmission and reception without searching the entire FM radio frequency band The present invention provides a method of minimizing the frequency determination time of a frequency adaptive radio transceiver by finding an initial spectrum-hole for wireless transmission and reception of a device, and immediately determining the found spectrum-hole as a use frequency of the radio transceiver.

In the wireless transmission / reception method using the frequency adaptation technique for achieving the above object, a frequency for allowing one radio transceiver and the other radio transceiver to perform a one-to-one wireless communication, but for a low-power short-range for compliance with unauthorized radio laws A wireless transmission / reception method using an adaptive technique, wherein a wireless transceiver for performing wireless transmission / reception moves a received electric field strength of an individual frequency signal received by moving the number of frequencies to be measured at a predetermined frequency shift interval from a preset starting frequency. Measuring; Setting a minimum value of the measured received electric field strength to a noise level; Resetting the reception frequency to a preset start frequency, and then measuring the received electric field strength of the received frequency signal by moving from the start frequency to a preset frequency shift interval; And determining a frequency at which the measured received electric field strength is smaller than a reference electric field strength, which is the sum of the noise level and a predetermined electric field strength, as a wireless transmit / receive frequency.

When the wireless transceiver determines the radio transmission frequency and transmits a synchronization signal using the determined transmission and reception frequency, the other radio transceiver receives the synchronization signal by searching the entire FM radio frequency band at a preset frequency movement interval In addition, the frequency determination notification signal is transmitted to one radio transceiver at a frequency of the received synchronization signal, thereby performing frequency synchronization between the radio transceiver of one side and the radio transceiver of the other side.

On the other hand, the one-to-one wireless transceiver using the frequency adaptation technology to achieve the above object is a low-power short-range wireless transceiver for complying with the unlicensed radio law, the signal to be transmitted to the outside as a frequency shift keying (FSK) signal A transmitter for modulating and transmitting the antenna through an antenna; A receiver which demodulates an FSK signal received through the antenna; The received electric field strength received through the receiver is measured according to a preset frequency shift interval and frequency shift frequency from a preset start frequency among FM radio broadcasting frequencies, and the minimum value is set to a noise level, and then the preset frequency is preset from the preset start frequency. If the received field strength of the received frequency signal is sequentially re-received by the FM radio broadcast signal at a frequency shift interval, and is smaller than the reference field strength, which is the sum of the noise level and a predetermined predetermined field strength, the radio having the received field strength is radio frequency. Control unit for determining the transmission and reception frequency.

The wireless transmission and reception method and apparatus using the frequency adaptation technology according to the present invention is a frequency or broadcast that is not used as a broadcast in any region of the FM radio broadcast frequency, but the reception field strength is weak, so that the FM radio broadcast listening is not possible, The efficiency of using limited frequency resources can be improved by allowing reuse and observing small power, short-range, and unauthorized radio laws.

In addition, the wireless transmission and reception method and apparatus using the frequency adaptation technology according to the present invention uses the information of one or both sides between the mobile wireless terminal and the base station by performing the recognition, analysis, determination of the optimal wireless network to use, etc. Unlike conventional frequency-aware technology, it can be applied to products such as computers, mice, keyboards, and printers that do not require a separate network configuration to perform one-to-one wireless communication, thereby simplifying the entire system and individual hardware while improving frequency utilization efficiency. It has an effect.

In addition, the wireless transmission and reception method and apparatus using the frequency adaptation technology according to the present invention by applying the frequency adaptation technology to remove the radio interference between the wireless transmission and reception device that complies with the small power, short-range, unlicensed radio laws, small power, short-range, unauthorized radio law There is an effect that can extend the use of the wireless transceiver that complies with.

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

1 shows a spectrum of an FM radio broadcast frequency measured in an arbitrary region. In general, an FM radio broadcast frequency band includes an FM radio station in an arbitrary region unless a position of the FM radio station is changed or a new FM radio broadcast frequency does not occur. There is no change in the radio broadcast frequency spectrum.

As shown in FIG. 1, using FM radio broadcast frequencies 101, 102, 103, 104, 107, 108, 109, 110, 112 that are sufficiently larger than any reference field strength 113 of FM radio broadcast frequencies. Radio broadcasts are normally listened to by the listener. However, FM radio using frequencies 106 and 111 that are not sufficiently greater than any reference field strength 113 of the FM radio broadcast frequencies, or frequencies 105 having an electric field strength less than any reference field strength 113. The broadcast has a large noise level, and the listener avoids listening.

Accordingly, frequencies 105, 106, and 111 that have a field strength not greater than or less than this reference field strength 113 and frequencies not used as an FM radio broadcast frequency can be used for purposes other than FM radio broadcast. If so, the utilization efficiency of the frequency can be improved. In the present invention, it is intended to find these frequencies and use them for applications other than FM broadcasting, i.e., frequencies of one-to-one short-range small output radio transceivers.

In an exemplary embodiment of the present invention, a one-to-one low power short-range wireless transceiver for efficiently using an FM radio broadcast frequency band may be configured to search for a frequency without an FM radio broadcast in a frequency range of a part of the first FM radio broadcast frequency band. The frequency shifts from the starting frequency to the preset frequency interval and the frequency of the frequency to be measured and samples the received field strength of each frequency.The minimum value of the measured received field strength is set as the noise level. To determine the received field strength value by FM radio broadcast frequency or spectrum-hole, an arbitrary field strength value, which is an experimental value, is set to set the reference field strength value for comparison with the received field strength to be equal to or greater than a preset noise level value. Will be set. Among the FM radio broadcasting frequencies, a frequency for which FM radio broadcasting is smoothly listened and a frequency including noise or a frequency without FM radio broadcasting are divided into a reference electric field sum based on a sum of a received electric field strength minimum value and an experimental electric field strength value. By setting, a frequency having an electric field strength of more than the reference electric field strength is determined by the existence of an FM radio broadcasting frequency in which the FM radio broadcasting listening is smooth, and a frequency below the electric field strength of the electric field is no FM radio broadcasting frequency or due to noise. The listener makes a judgment on the frequency of avoiding listening.

In the FM radio broadcasting frequency band, any frequency field strength measurement method measures a plurality of times the center frequency of the FM radio broadcasting frequency in which the maximum field energy exists in the FM radio broadcasting frequency for a predetermined time, and calculates the average value of the field strength values measured in a large number. It is set to the electric field strength value of the received frequency. Figure 2 shows an example of the energy distribution according to the frequency of the FM radio broadcasting frequency measured at the center frequency of 99.9 MHz complying with the FM radio broadcasting propagation method of the center frequency ± 100 kHz according to this embodiment of the present invention.

3 is a block diagram of a wireless transceiver according to an embodiment of the present invention.

As shown in FIG. 3, the wireless transceiver according to the present invention includes a transmitter 302 for modulating a signal to be transmitted to a radio transmission frequency, an antenna 301 for radio transmission of a frequency signal converted by the transmitter, A receiver 311 for demodulating a radio reception frequency received from the antenna 301, a first switch 312 connecting the antenna 301 to a transmitter 302 or a receiver 311, and a radio transceiver And a control unit 306 for determining the wireless transmission / reception frequency to be used, digital data input / output with an external device, and the components.

The transmitter 302 is an FSK modulator 304 for directly converting digital information to be transmitted to a frequency shift keying (FSK) signal under the control of the controller 306, and FSK-modulated wireless transmission. And a power amplifier 303 for amplifying the signal and wirelessly transmitting it through the antenna 301.

The receiving unit 311 is a low noise amplifier 310 for amplifying the FM or FSK signal received from the antenna 301, and FSK for directly converting (demodulating) the FSK signal amplified through the low noise amplifier 310 (Direct Down Conversion). A demodulator 305, a detector 308 for detecting a DC voltage of the FM signal amplified by the low noise amplifier 310 for measuring the received electric field strength, and the low noise amplifier 310 FSK demodulator 305 Or a second switch 309 connecting to the detector 308.

The control unit 306 controls the first switch 312 and the second switch 309, and measures the received electric field strength of the FM signal detected through the detector 308 of the receiver 311 in the wireless transceiver The frequency to be used is determined, and the digital data input / output of the external device 307 is controlled. The external device 307 connected to the controller 306 is a device for performing input / output of short-range short-range wireless digital data, and may be, for example, a keyboard, a mouse, a printer, or the like of a personal computer.

Hereinafter, a process of performing a short range wireless transmission / reception through the wireless transmission / reception apparatus according to the present invention having the above configuration will be described.

4 is a flowchart illustrating a process of determining a frequency to be used as a wireless transmit / receive frequency at one side of a wireless transmit / receive apparatus that performs communication according to an embodiment of the present invention.

Step S101: In order to determine a wireless transmission / reception frequency to be used between the first wireless transmission / reception apparatuses, an environment of the measurement frequency is set. The measurement frequency configuration includes setting a start frequency (S), setting a frequency shift interval (A), setting a number of measurement frequencies (C), and setting an arbitrary field strength (D).

In the embodiment of the present invention, the start frequency (S) is a frequency to start the first measurement of the FM radio broadcasting frequency (88MHz ~ 108MHz), the frequency shift interval (A) is to move the frequency and measure the received electric field strength In one embodiment, the moving frequency may be +100 Hz, +200 Hz, or the like, and the number C of measurement frequencies indicates the number of sample measurement frequencies for measuring the noise level of the radio transceiver.

In addition, the arbitrary electric field strength (D) is a value for setting a reference electric field strength for finding a spectral hole in the FM radio frequency band, and the reference electric field strength is a sum of the measured noise level and the electric field strength (D). do.

Step S102: The control unit 306 switches the first switch 312 in the direction of the receiving unit 311 and measures the second switch 309 in order to measure the received electric field strength of individual frequencies in the FM radio broadcasting frequency band. Direction).

Step S103: The control unit 306 moves the reception frequency by the number of measurement frequencies C from the start frequency S set in the measurement frequency configuration to the preset frequency shift interval A and is output through the detector 308. Measure the received field strength of individual frequencies in the FM radio broadcast frequency band.

Step S104: The control unit 306 compares the received field strengths of the individual frequencies to be measured, respectively, and sets the minimum value having the smallest received field strength to the noise level B. FIG. The measured noise level B will be the field strength of the noise without the FM radio broadcast signal in the current propagation environment or the noise level of the radio transceiver.

Step S105: Once the noise level B is determined, reset the reception frequency to the start frequency S.

Step S106: After the reception frequency is reset to the starting frequency S, it moves from the starting frequency S to the frequency shift interval A and re-measures the received field strength.

Step S107: The received field strength measured at each frequency is compared with the sum of the noise level (B) and any field strength (D) that is an experimental value, so that the measured received field strength is equal to the noise level (B) and any electric field. The frequency below the sum of the intensities D is determined. The reason for setting an arbitrary field strength (D) is that the noise level of the wireless receiver can change due to changes in the propagation environment, such as ambient temperature and power supply voltage, over time, so do not directly compare the received field strength and noise level at each frequency. In order to buffer a change in the noise level without a noise, it is to have a reference electric field strength having a value greater than an arbitrary value than the noise level. FIG. 5 is an example of a spectrum of an FM radio broadcast frequency indicating such an arbitrary field strength. The setting of an arbitrary field strength (D) is an experimental value, and includes a received field strength that is larger than the noise level (B) but incapable of listening to a radio broadcast. It is set to a possible value. The sum of the noise level B and the arbitrary field strength D becomes the reference field strength value.

Step S108: When a frequency is first detected in which the measured received electric field strength is less than the sum of the noise level B and the arbitrary electric field strength D, the frequency is determined as the frequency used by the radio transceiver.

Steps S109 and S110: When the radio transmission / reception frequency is determined, the second switch 309 is turned toward the FSK demodulator 305 (S109), and the first switch 312 is appropriately switched according to the transmission / reception state of the radio transceiver. By performing the frequency synchronization process with the other wireless transceiver to perform the communication (S110).

6 is a flowchart illustrating a process of performing frequency synchronization between radio transceivers performing radio communication according to an embodiment of the present invention. In FIG. 6, the first switch 312 and the second switch 309 of the radio transceiver are switched by the control unit 306 according to a communication mode, that is, a transmission mode and a reception mode. The description will be omitted.

Step S201: The radio transceiver A1 of one side having determined the transmission / reception frequency through the process of FIG. 4 is a transmission mode capable of transmitting a synchronization signal and a reception capable of receiving a frequency determination notification signal from the other radio transceiver A2. The mode will change periodically.

Step S202: One side wireless transceiver A1 transmits a synchronization signal using the transmission and reception frequency determined in FIG. 4, wherein the synchronization signal includes the same unique number of both sides of the wireless transmission and reception apparatus for transmitting and receiving the synchronization signal. That is, the synchronization signal includes a unique number of a device configured to be the same in one radio transceiver (A1) and the other radio transceiver (B1) that performs wireless communication, and wireless transmission and reception through the unique number included in the synchronization signal The device can identify that it is a synchronization signal coming to it. In addition to the unique number of the radio transceiver, the synchronization signal may include a preamble, an error check code, an end code, and the like used for normal communication data. Since the structure of the communication data follows the conventional radio communication data structure, Description thereof will be omitted.

Step S203: The other radio transceiver A2 simultaneously searches for a frequency synchronization signal by moving the entire FM radio frequency band at a predetermined frequency interval A at the same time of applying power for the operation of the transceiver.

Step S204, S205: when the other side wireless transceiver A2 is detected, the communication mode is changed from the reception mode to the transmission mode to transmit the frequency determination notification signal for a predetermined time using the frequency from which the synchronization signal is received. Subsequently (S204), the corresponding frequency for transmitting the frequency determination notification signal is set to the communication frequency to switch the transmission / reception mode state to the normal state according to the preset communication method (S205).

Step S206: Meanwhile, the one side wireless transceiver A1 which has received the frequency determination notification signal from the other side wireless transceiver A2 sets the communication frequency to the frequency at which the frequency determination notification signal has been received and sets the transmission / reception mode to the preset communication scheme. Therefore, it returns to the normal state.

Step S207: One wireless transceiver A1 and the other wireless transceiver A2 perform communication for transmitting and receiving wireless data using a frequency determined according to a preset communication scheme.

The frequency occupancy priority between the frequency adaptive radio transceiver and another frequency adaptive radio transceiver according to the present invention is in the first-occupied apparatus when one frequency of the frequency-adaptive radio transceiver preempts, and then another frequency. The adaptive radio transceiver is regarded as a primary user who has the authority to use the frequency for the preempted frequency.

In the above-described embodiment of the present invention, the FSK demodulator 305 and the detector 308 are provided in the receiver 311, and the second signal 309 is alternatively connected to the low noise amplifier 310. Since the received electric field strength may use the magnitude of the signal demodulated by the FSK demodulator 305, the second switch 309 and the detector 308 may be omitted from the receiver 311.

As described above, the method and apparatus for wireless transmission and reception using the frequency adaptation technology according to the present invention are not limited to the above-described embodiments, and are provided by those skilled in the art to which the present invention pertains. Of course, various modifications and variations can be made within the equivalent scope of the claims to be described.

1 is a spectrum of FM radio broadcast frequencies measured in an arbitrary region,

2 is an example of an FM radio broadcast frequency measured at a center frequency 99.9 MHz complying with the FM radio broadcast radio wave method of a center frequency ± 100 Hz;

3 is a block diagram of a wireless transceiver according to the present invention;

4 is a flowchart illustrating a process of determining a frequency to be used as a wireless transmit / receive frequency at one side of a wireless transceiver that performs communication according to the present invention;

5 is an example of a spectrum of an FM radio broadcast frequency showing an arbitrary field strength in accordance with the present invention;

6 is a flowchart illustrating a process of performing frequency synchronization between wireless transceivers performing wireless communication according to the present invention.

[Description of Drawings]

301: antenna 302: transmitter

303: power amplifier 304: FSK modulator

305: FSK demodulation unit 306: control unit

307: external device 308: detector

309: second switch 310: low noise amplifier

311: receiver 312: first switch

Claims (5)

delete A wireless transmitting / receiving method using a frequency adaptation technology for allowing one side wireless transceiver A1 and another side wireless transceiver A2 to perform one-to-one wireless communication, but to perform communication for low power and short-range for complying with an unlicensed radio law. (a) Receiving electric field strength of a received frequency signal while moving by the number of measurement frequencies (C) from a preset start frequency (S) to a frequency shift interval (A) in one radio transceiver (A1) for performing radio transmission and reception. Measuring; (b) setting a minimum value of the measured received electric field strength to a noise level (B); (c) measuring a received electric field strength of the received frequency signal while resetting the reception frequency to the preset start frequency (S) and moving from the reset start frequency (S) to a frequency shift interval (A); (d) determining a frequency having the received field strength as a wireless transmit / receive frequency when the measured received field strength is less than a reference field strength, which is a sum of the noise level (B) and a predetermined predetermined field strength (D); (e) transmitting a synchronization signal including a unique number of the device to the other radio transceiver A2 using the transmission / reception frequency determined by the radio transceiver A1; (f) The other side wireless transceiver A2 searches for a synchronization signal in the entire FM radio broadcasting frequency band, and then transmits a frequency determination notification signal to one side wireless transceiver A1 using the found frequency of the synchronization signal. A step of performing frequency synchronization between the radio transceiver A1 and the other radio transceiver A2; wireless transmission and reception method using a frequency adaptation technology comprising a. delete A radio transceiver that uses one-to-one radio communication, but complies with small power, near-unlicensed radio laws and uses frequency adaptation technology. A transmitter 302 for modulating a digital signal to be transmitted to an FSK signal and transmitting the same through an antenna 301; A receiver 311 for demodulating the FSK signal received through the antenna 301; After measuring the received electric field strength of the FM signal received through the receiver 311 in a preset frequency band and setting the minimum value to the noise level (B), the FM signal is sequentially received in the preset frequency band and received. The control unit 306 for determining a frequency having the received electric field strength as a wireless transmit / receive frequency when the received electric field strength of the frequency signal is smaller than the reference electric field strength which is the sum of the noise level B and the predetermined electric field strength D. Including; The antenna 301 is a wireless transmission and reception device using a frequency adaptation technology, characterized in that the first connection 312 controlled by the control unit 306 and alternatively connected to the transmitter 302 or the receiver 311 . The method of claim 4, wherein The receiver 311 includes a low noise amplifier 310 for low noise amplifying the FSK signal received from the antenna 301, an FSK demodulator 305 for demodulating the low noise amplified FSK signal through the low noise amplifier 310, and A detector 308 for detecting the DC voltage of the low noise amplified FM signal through the low noise amplifier 310, and one side is connected to the low noise amplifier 310, the other side of the FSK demodulator 305 or the detector 308 Wireless transmission and reception apparatus using a frequency adaptation technology, characterized in that it comprises a second switch (309) which is alternatively connected to one side.

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