CN117134801A - Radio frequency read-write equipment, gain adjusting method, device and storage medium - Google Patents
Radio frequency read-write equipment, gain adjusting method, device and storage medium Download PDFInfo
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- CN117134801A CN117134801A CN202210542895.6A CN202210542895A CN117134801A CN 117134801 A CN117134801 A CN 117134801A CN 202210542895 A CN202210542895 A CN 202210542895A CN 117134801 A CN117134801 A CN 117134801A
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/38—Transceivers, i.e. devices in which transmitter and receiver form a structural unit and in which at least one part is used for functions of transmitting and receiving
- H04B1/40—Circuits
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
- G06K7/00—Methods or arrangements for sensing record carriers, e.g. for reading patterns
- G06K7/0008—General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
- Y02D30/00—Reducing energy consumption in communication networks
- Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks
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Abstract
The application provides a radio frequency read-write equipment, a gain adjusting method, a device and a storage medium, wherein the radio frequency read-write equipment comprises: a radio frequency transceiver; the radio frequency amplifying unit is used for amplifying and outputting radio frequency signals transmitted by the radio frequency transceiver; the antenna end of the coupler is electrically connected with the antenna, the input end of the coupler is electrically connected with the radio frequency amplifying unit, and the coupling end and the isolation degree end of the coupler are electrically connected with the radio frequency transceiver; the attenuation unit is arranged between the isolation degree end of the coupler and the receiving end of the radio frequency transceiver; the control unit is used for detecting the output power of the radio frequency amplifying unit through the coupling end of the coupler, detecting the reflected power of the antenna end through the isolation end of the coupler, calculating the return loss of the antenna according to the output power and the reflected power, determining a target attenuation value according to the return loss of the antenna, and controlling the attenuation unit to adjust the link attenuation according to the target attenuation value. The application can improve the sensitivity of the radio frequency read-write equipment.
Description
Technical Field
The present application relates to the field of radio frequency technologies, and in particular, to a radio frequency read-write device, a gain adjustment method, a gain adjustment device, and a storage medium.
Background
Along with the development of RFID technology, the application of passive radio frequency identification technology is more and more extensive, and in ultrahigh frequency and microwave frequency bands, the passive radio frequency identification technology mainly realizes reading and writing based on the electromagnetic wave backscattering principle. However, when the read-write device transmits a carrier signal, a part of the carrier may generate reflection leakage due to interference factors such as antenna standing waves, working channels, environmental reflection, etc., which interfere with a useful signal, resulting in deterioration of sensitivity.
Disclosure of Invention
The application provides radio frequency read-write equipment, a gain adjusting method, a gain adjusting device and a storage medium, which can improve sensitivity.
The application provides a radio frequency read-write equipment, comprising:
a radio frequency transceiver;
the radio frequency amplifying unit is used for amplifying and outputting radio frequency signals transmitted by the radio frequency transceiver;
the antenna end of the coupler is electrically connected with the antenna, the input end of the coupler is electrically connected with the radio frequency amplifying unit, the coupling end and the isolation end of the coupler are electrically connected with the radio frequency transceiver, and the coupler is used for transmitting the radio frequency signal output after being amplified by the radio frequency amplifying unit through the antenna and coupling the radio frequency signal to the radio frequency transceiver through the coupling end for carrier cancellation; the antenna is also used for outputting the radio frequency reflected signals received by the antenna to the radio frequency transceiver through the isolation degree end;
the attenuation unit is arranged between the isolation degree end of the coupler and the receiving end of the radio frequency transceiver and is used for providing link attenuation for the radio frequency reflection signal;
the control unit is used for detecting the output power of the radio frequency amplifying unit through the coupling end of the coupler, detecting the reflected power of the antenna end through the isolation end of the coupler, calculating the antenna return loss according to the output power and the reflected power, determining a target attenuation value according to the antenna return loss, the coupling degree of the coupler, the maximum transmitting power of the radio frequency transceiver and the maximum carrier leakage, and controlling the attenuation unit to adjust the link attenuation according to the target attenuation value.
In one embodiment, the target attenuation value is inversely related to the antenna return loss.
In one embodiment, the control unit comprises:
the detection circuit is respectively and electrically connected with the coupling end and the isolation degree end of the coupler and is used for collecting the output signal of the radio frequency amplifying unit and the receiving signal of the antenna end;
the controller is electrically connected with the detection circuit, and is used for determining the output power according to the output signal of the radio frequency amplifying unit acquired by the detection circuit, determining the reflected power according to the receiving signal of the antenna end acquired by the detection circuit, calculating the antenna return loss according to the output power and the reflected power, determining a target attenuation value according to the antenna return loss, the coupling degree of the coupler, the maximum transmitting power of the radio frequency transceiver and the maximum carrier leakage, and controlling the attenuation unit to adjust the link attenuation according to the target attenuation value.
In one embodiment, the detection circuit includes: the first detector, the second detector, the first sampling resistor and the second sampling resistor;
the input end of the first detector is electrically connected with the first end of the first sampling resistor, and the output end of the first detector is electrically connected with the controller;
the second end of the first sampling resistor is electrically connected with the coupling end of the coupler;
the input end of the second detector is electrically connected with the first end of the second sampling resistor, and the output end of the second detector is electrically connected with the controller;
and the second end of the second sampling resistor is electrically connected with the isolation degree end of the coupler.
In one embodiment, the attenuation unit includes:
the first end of the adjustable attenuator is electrically connected with the isolation degree end of the coupler, the second end of the adjustable attenuator is electrically connected with the radio frequency transceiver, and the control end of the adjustable attenuator is electrically connected with the control unit.
In one embodiment, the attenuation unit comprises a first selection switch, a second selection switch and a plurality of fixed resistance attenuators;
the first end of the first selection switch is electrically connected with the isolation degree end of the coupler, the second ends of the first selection switch are respectively electrically connected with the first ends of the fixed resistance attenuators, and the control end of the first selection switch is electrically connected with the control unit;
the first ends of the second selection switches are respectively and electrically connected with the second ends of the fixed resistor attenuators, the second ends of the second selection switches are electrically connected with the radio-frequency transceiver, and the control ends of the second selection switches are electrically connected with the control unit;
the control unit is used for controlling the first selection switch and the second selection switch to select and conduct a passage where one fixed resistance attenuator is located according to the target attenuation value.
The application also provides a gain adjusting method applied to the control unit in the radio frequency read-write equipment according to any embodiment, and the method comprises the following steps:
obtaining output power of a radio frequency amplifying unit and reflected power of an antenna end of a coupler;
calculating the return loss of the antenna according to the output power and the reflected power;
determining a target attenuation value according to the antenna return loss, the coupling degree of the coupler, the maximum transmitting power of the radio frequency transceiver and the maximum carrier leakage;
and controlling an attenuation unit to adjust the link attenuation of the receiving link according to the target attenuation value.
In one embodiment, the target attenuation value is inversely related to the antenna return loss.
In one embodiment, before the step of obtaining the output power of the rf amplifying unit and the reflected power of the antenna end of the coupler, the method further includes:
and responding to the inventory command sent by the upper computer, and controlling the radio frequency transceiver to emit a radio frequency signal until inventory is completed.
In one embodiment, after the step of calculating the return loss of the antenna according to the output power and the reflected power, the method further includes:
and if the return loss of the antenna is smaller than a preset threshold value, stopping inventory and giving an alarm.
The application also provides a gain adjusting device applied to the control unit in the radio frequency read-write equipment according to any embodiment, which comprises:
the power acquisition module is used for acquiring the output power of the radio frequency amplification unit and the reflected power of the antenna end of the coupler;
the antenna return loss calculation module is used for calculating the antenna return loss according to the output power and the reflected power;
the attenuation value determining module is used for determining a target attenuation value according to the antenna return loss, the coupling degree of the coupler, the maximum transmitting power of the radio frequency transceiver and the maximum carrier leakage;
and the attenuation adjusting module is used for controlling the attenuation unit to adjust the link attenuation of the receiving link according to the target attenuation value.
A storage medium, characterized by: the storage medium has stored therein computer readable instructions which, when executed by one or more processors, cause the one or more processors to perform the steps of the gain adjustment method as described in any of the embodiments above.
From the above technical solutions, the embodiment of the present application has the following advantages:
according to the radio frequency read-write equipment, the gain adjusting method, the device and the storage medium, the control unit is electrically connected with the coupling end and the isolation end of the coupler, the output power of the radio frequency amplifying unit and the reflected power of the antenna end are detected, the antenna return loss of the radio frequency read-write equipment is calculated, the target attenuation value is determined according to the antenna return loss, the coupling degree of the coupler, the maximum transmitting power of the radio frequency transceiver and the maximum carrier leakage, the attenuation of the receiving link is dynamically adjusted according to the target attenuation value, and as the size of the antenna return loss and the antenna standing wave form a negative correlation, the size of the antenna standing wave depends on the output power and the reflected power, the reflected power can be dynamically changed based on environmental interference.
Drawings
In order to more clearly illustrate the embodiments of the application or the technical solutions of the prior art, the drawings which are used in the description of the embodiments or the prior art will be briefly described, it being obvious that the drawings in the description below are only some embodiments of the application, and that other drawings can be obtained from these drawings without inventive faculty for a person skilled in the art.
FIG. 1 is a block diagram of a RF read/write device in one embodiment;
FIG. 2 is a block diagram of a radio frequency read/write device according to another embodiment;
FIG. 3 is a block diagram of a radio frequency read/write device according to yet another embodiment;
FIG. 4 is a schematic circuit diagram of an attenuation unit according to an embodiment;
FIG. 5 is a flow chart of a gain adjustment method according to one embodiment;
fig. 6 is a schematic flow chart of a gain adjusting device in one embodiment.
Detailed Description
The following description of the embodiments of the present application will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.
The embodiment of the application provides a radio frequency read-write device 100, as shown in fig. 1, which comprises a radio frequency transceiver 110, a radio frequency amplifying unit 120, a coupler 130, an attenuation unit 140 and a control unit 150. Wherein the rf transceiver 110 is configured to transmit rf signals and also to receive reflected signals via the antenna 200. In one embodiment, the RF transceiver 110 is the main chip of the RF read/write device 100.
The rf amplifying unit 120 is disposed in a transmitting path of the rf read/write device 100, and is configured to amplify the rf signal transmitted by the rf transceiver 110 and output the amplified rf signal to the coupler 130. In one embodiment, the rf amplifying unit 120 includes an rf power amplifier; in some embodiments, the rf read/write device 100 is configured with a plurality of different channels, and can work in different frequency bands, and the rf amplifying unit 120 further includes a filter and an rf switch, where the rf switch selectively turns on a path where the different filters are located, so as to output an rf signal in a desired frequency band.
The coupler 130 is configured with an antenna terminal OUT for electrically connecting with the antenna 200, an input terminal IN electrically connected with the rf amplifying unit 120, a coupling terminal CP electrically connected with a carrier cancellation input terminal of the rf transceiver 110, and an isolation terminal ISO electrically connected with a receiving terminal of the rf transceiver 110. The coupler CP is configured to transmit the radio frequency signal output after the amplification of the radio frequency amplifying unit 120 through the antenna 200, and couple the radio frequency signal to the radio frequency transceiver 110 through the coupling end CP to perform carrier cancellation; and is further configured to output the radio frequency reflected signal received by the antenna 200 to the radio frequency transceiver 110 via the isolation terminal ISO. In one embodiment, coupler 130 is a directional coupler or circulator.
The attenuation unit 140 is disposed between the isolation end ISO of the coupler 130 and the receiving end of the radio frequency transceiver 110, and is configured to provide link attenuation for the radio frequency reflected signal, adjust the gain of the receiving link, so as to improve the noise figure of the radio frequency read/write device 100, and optimize the sensitivity.
The control unit 150 is electrically connected to the rf transceiver 110, the attenuation unit 140, and the coupler 130, and is configured to detect the output power of the rf amplifying unit 120 through the coupling end CP of the coupler 130, detect the reflected power of the antenna end OUT through the isolation end ISO of the coupler 130, calculate the antenna return loss according to the output power and the reflected power, determine a target attenuation value according to the antenna return loss, the coupling degree of the coupler 130, the maximum transmitting power of the rf transceiver 110, and the maximum carrier leakage, and control the attenuation unit 140 to adjust the link attenuation according to the target attenuation value.
After the radio frequency transceiver 110 transmits the radio frequency signal, the radio frequency signal is amplified by the radio frequency amplifying unit 120 and then is input to the input end IN of the coupler 130, one path of signal is coupled by the coupler 130 from the input signals, and is output to the radio frequency transceiver 110 through the coupling end CP of the coupler 130, so as to provide a reference signal for carrier cancellation, the remaining main signal is output to the antenna 200 through the antenna end OUT of the coupler 130, radiated outwards through the antenna 200, backscattered by the RFID tag, the reflected signal is received by the antenna 200 and transmitted to the coupler 130, the received reflected signal is output through the isolation end ISO by the coupler 130, and transmitted to the radio frequency transceiver 110 through the attenuation unit 140. The control unit 150 determines the output power of the radio frequency signal by collecting the signal output by the coupling end CP, and determines the reflected power of the reflected signal by collecting the signal output by the isolation end ISO, and calculates the antenna return loss of the radio frequency read-write device 100 according to the output power and the reflected power, that is, the magnitude of the antenna return loss and the antenna standing wave form a negative correlation, and the magnitude of the antenna standing wave depends on the magnitude of the output power and the reflected power, and the reflected power is subject to environmental interference and is possibly changed.
In the prior art, in order to optimize the noise coefficient of a radio frequency channel, an attenuator is arranged on a transmitting channel or a receiving channel to provide link attenuation, the noise coefficient of the radio frequency channel is regulated, the noise coefficient can influence the sensitivity of a radio frequency device, and a fixed attenuator is usually arranged, but for RFID radio frequency read-write equipment, due to factors such as antenna return loss, working signals, environment reflection and the like, a part of radio frequency signals can reflect and leak to an antenna end (namely carrier leakage), interfere with useful signals and cause sensitivity deterioration, and the part of interference can be changed continuously, if the fixed attenuator is adopted to provide attenuation, although the carrier leakage processed by a final radio frequency transceiver can be ensured to be within the maximum carrier leakage, the link attenuation can have certain deterioration influence on the sensitivity when the carrier leakage is small.
In one embodiment, the target attenuation value is inversely related to the antenna return loss.
The higher the antenna return loss, the smaller the carrier leakage, and the target attenuation value can be properly reduced; when the return loss of the antenna is low, the carrier leakage is high, and the target attenuation value needs to be improved at the moment, so that the link attenuation is improved, and the carrier leakage is inhibited.
In one embodiment, the target attenuation value is calculated according to the following formula:
A＝P 1ma -S11-L-J max
wherein A is the target attenuation value, P 1ma For the maximum transmitting power of the radio frequency transceiver, S11 is the antenna return loss, the antenna return loss s11= -20 log10[ (vswr+1)/(VSWR-1), VSWR is the antenna standing wave, L is the coupling degree of the coupler, J max And if the calculation result of the target attenuation value is smaller than 0, determining the target attenuation value as 0 for the maximum carrier leakage which can be processed by the radio frequency transceiver.
In some embodiments, a negative correlation curve of the target attenuation value and the antenna return loss may be pre-tested, and the target attenuation value corresponding to the antenna return loss lookup curve may be found.
In one embodiment, as shown in fig. 2, the control unit 150 includes a detection circuit 151 and a controller 152. The detection circuit 151 is electrically connected to the coupling end CP, the isolation end ISO, and the controller 152 of the coupler 130, where the detection circuit 151 is configured to collect an output signal of the radio frequency amplifying unit 129 and a received signal of the antenna end OUT; the controller 152 is configured to determine an output power according to an output signal of the rf amplifying unit 120 collected by the detection circuit 151, determine a reflected power according to a received signal of the antenna end OUT collected by the detection circuit 151, calculate an antenna return loss according to the output power and the reflected power, determine a target attenuation value according to the antenna return loss, the coupling degree of the coupler 130, the maximum transmitting power of the rf transceiver 110, and the maximum carrier leakage, and control the attenuation unit 140 to adjust the link attenuation according to the target attenuation value.
The output signal of the radio frequency amplifying unit 120 is coupled to a coupling end CP through a coupler 130, the detection circuit 151 performs acquisition feedback to the controller 152 through the coupling end CP, and the controller 152 determines the output power of the output signal according to the acquisition data fed back by the detection circuit 151; the antenna 200 receives the reflected signal and outputs the received signal to the antenna terminal OUT, the coupler 130 couples the received signal of the antenna terminal OUT to the isolation terminal ISO, the detection circuit 151 collects the received signal through the isolation terminal ISO and feeds back the collected signal to the controller 152, and the controller 152 determines the reflected power according to the collected data fed back by the detection circuit 151. The controller 152 may calculate an antenna return loss based on the determined output power and reflected power, and further determine a target attenuation value according to the antenna return loss, the coupling degree of the coupler 130, the maximum transmit power of the radio frequency transceiver 110, and the maximum carrier leakage, and control the attenuation unit 140 to provide link attenuation corresponding to the target attenuation value according to the target attenuation value, so as to implement dynamic gain adjustment of the receiving link.
In one embodiment, as shown in fig. 3, the detection circuit 151 includes: a first detector 1511, a second detector 1512, a first sampling resistor R1, and a second sampling resistor R2. The input end of the first detector 1511 is electrically connected to the first end of the first sampling resistor R1, and the output end of the first detector 1511 is electrically connected to the controller 152; the second end of the first sampling resistor R1 is electrically connected to the coupling end CP of the coupler 130; an input terminal of the second detector 1512 is electrically connected to the first terminal of the second sampling resistor R2, and an output terminal of the second detector 1512 is electrically connected to the controller 152; a second end of the second sampling resistor R2 is electrically connected to the isolation end ISO of the coupler 130.
The coupler 130 couples the output signal to the coupling end CP, the first detector 1511 collects the output signal through the first sampling resistor R1, and outputs a first dc signal to the controller 152, and the controller 152 calculates the output power of the output signal according to the first dc signal. The coupler 130 couples the received signal to the isolation terminal ISO, the second detector 1512 collects the received signal through the second sampling resistor R2, and outputs a second direct current signal to the controller 152, and the controller 152 calculates the reflected power of the received signal according to the second direct current signal.
In one embodiment, the attenuation unit 140 includes: an adjustable attenuator, a first end of which is electrically connected to the isolation end ISO of the coupler 130, a second end of which is electrically connected to the radio frequency transceiver 110, and a control end of which is electrically connected to the control unit 150.
The adjustable attenuator is an attenuator chip capable of providing link attenuation according to the control of the control unit 150. The control unit 150 controls the adjustable attenuator to provide a link attenuation equal to the target attenuation value by outputting a control signal to a control terminal of the adjustable attenuator.
The link attenuation is provided by the adjustable attenuator, so that the attenuation value can be adjusted more flexibly.
In one embodiment, the adjustable attenuator is selected according to a maximum attenuation value, where the maximum attenuation value is equal to the maximum transmit power of the radio frequency transceiver minus a standing wave alarm threshold of the radio frequency read-write device, and minus the coupling degree of the coupler.
In one embodiment, as shown in fig. 4, the attenuation unit 140 includes a first selection switch 141, a second selection switch 142, and a plurality of fixed resistance attenuators 143. Wherein, a first end of the first selection switch 141 is electrically connected to the isolation end ISO of the coupler 130, a plurality of second ends of the first selection switch 141 are respectively electrically connected to the first ends of the fixed resistance attenuators 143, and a control end of the first selection switch 141 is electrically connected to the control unit 150; the first ends of the second selection switch 142 are respectively electrically connected with the second ends of the fixed resistance attenuators 143, the second end of the second selection switch 142 is electrically connected with the radio frequency transceiver 110, and the control end of the second selection switch 142 is electrically connected with the control unit 150; the control unit 150 is configured to control the first selection switch 141 and the second selection switch 142 to selectively turn on a path where one of the fixed resistance attenuators 143 is located according to the target attenuation value.
The first selection switch 141 and the second selection switch 142 are SPNT (single pole multiple throw) radio frequency switches, the attenuation values of the fixed resistance attenuators 143 are different, the control unit 150 selects a path in which an appropriate fixed resistance attenuator is located according to the target attenuation value, controls the first selection switch 141 to conduct a port electrically connected to the selected fixed resistance attenuator, and controls the second selection switch 142 to conduct a port electrically connected to the selected fixed resistance attenuator. If there is no fixed resistance attenuator equal to the target attenuation value, a fixed resistance attenuator closest to the target attenuation value and greater than the target attenuation value is selected.
According to the embodiment, the SPNT radio frequency switch is matched with a plurality of fixed resistor attenuators to adjust attenuation values, so that circuit cost can be saved.
It will be understood that when an element is referred to as being "connected" to another element, it can be directly connected to the other element or be connected to the other element through intervening elements. Further, "connection" in the following embodiments should be understood as "electrical connection", "communication connection", and the like if there is transmission of electrical signals or data between objects to be connected.
The embodiment of the present application further provides a gain adjustment method, which is applied to the control unit 150 in the radio frequency read-write device 100 in fig. 1, as shown in fig. 5, and the method includes steps S501 to S504, where:
step S501, obtaining the output power of a radio frequency amplifying unit and the reflected power of the antenna end of a coupler;
step S502, calculating the return loss of the antenna according to the output power and the reflected power;
step S503, determining a target attenuation value according to the antenna return loss, the coupling degree of the coupler, the maximum transmitting power of the radio frequency transceiver and the maximum carrier leakage;
step S504, the attenuation unit is controlled to adjust the link attenuation of the receiving link according to the target attenuation value.
After the radio frequency transceiver transmits radio frequency signals, the radio frequency signals are amplified by the radio frequency amplifying unit and then input to the input end IN of the coupler, one path of signals are coupled by the coupler from the input signals and output to the radio frequency transceiver through the coupling end CP of the coupler, so as to provide carrier cancellation reference signals, the rest main signals are output to the antenna through the antenna end OUT of the coupler, radiated outwards through the antenna, backscattered through the RFID tag, received reflected signals by the antenna are transmitted to the coupler, and the coupler outputs the received reflected signals through the isolation end ISO and transmits the received reflected signals to the radio frequency transceiver through the attenuation unit. The control unit determines the output power of the radio frequency signal by collecting the signal output by the coupling end CP, and determines the reflection power of the reflection signal by collecting the signal output by the isolation end ISO, and calculates the antenna return loss of the radio frequency read-write equipment according to the output power and the reflection power, namely the size of the antenna return loss depends on the output power and the reflection power, and the reflection power is subject to the change of environmental interference, so that the antenna return loss is also likely to change.
In the prior art, in order to optimize the noise coefficient of a radio frequency channel, an attenuator is arranged on a transmitting channel or a receiving channel to provide link attenuation, the noise coefficient of the radio frequency channel is regulated, the noise coefficient can influence the sensitivity of a radio frequency device, and a fixed attenuator is usually arranged, but for RFID radio frequency read-write equipment, due to factors such as antenna return loss, working signals, environment reflection and the like, a part of radio frequency signals can reflect and leak to an antenna end (namely carrier leakage), interfere with useful signals and cause sensitivity deterioration, and the part of interference can be changed continuously, if the fixed attenuator is adopted to provide attenuation, although the carrier leakage processed by a final radio frequency transceiver can be ensured to be within the maximum carrier leakage, the link attenuation can have certain deterioration influence on the sensitivity when the carrier leakage is small.
In one embodiment, the target attenuation value is inversely related to the antenna return loss.
The higher the antenna return loss, the smaller the carrier leakage, and the target attenuation value can be properly reduced; when the return loss of the antenna is low, the carrier leakage is high, and the target attenuation value needs to be improved at the moment, so that the link attenuation is improved, and the carrier leakage is inhibited.
In one embodiment, the target attenuation value is calculated according to the following formula:
A＝P 1max -S11-L-J max
wherein A is the target attenuation value, P 1max For the maximum transmitting power of the radio frequency transceiver, S11 is the return loss of the antenna, L is the coupling degree of the coupler, J max And if the calculation result of the target attenuation value is smaller than 0, determining the target attenuation value as 0 for the maximum carrier leakage which can be processed by the radio frequency transceiver.
In some embodiments, a negative correlation curve of the target attenuation value and the antenna return loss may be pre-tested, and the target attenuation value corresponding to the antenna return loss lookup curve may be found.
In one embodiment, before the step of obtaining the output power of the rf amplifying unit and the reflected power of the antenna end of the coupler, the method further includes:
and responding to the inventory command sent by the upper computer, and controlling the radio frequency transceiver to emit a radio frequency signal until inventory is completed.
The upper computer is used for controlling the radio frequency read-write equipment to carry out inventory, when inventory is needed, the upper computer sends an inventory instruction to the control unit of the radio frequency read-write equipment, and the control unit controls the radio frequency transceiver to emit radio frequency signals according to the inventory instruction until an inventory task indicated by the inventory instruction is completed.
In one embodiment, after the step of calculating the return loss of the antenna according to the output power and the reflected power, the method further includes:
if the return loss of the antenna is smaller than the preset threshold value, the inventory is stopped and an alarm is sent out.
The preset threshold value is the minimum antenna return loss of the normal inventory of the radio frequency read-write equipment, and when the antenna return loss is lower than the preset threshold value, the inventory cannot be normally performed, so that the inventory is stopped and an alarm is sent to prompt a user when the antenna return loss is lower than the preset threshold value.
It should be understood that, although the steps in the flowchart of fig. 5 are shown in sequence as indicated by the arrows, the steps are not necessarily performed in sequence as indicated by the arrows. The steps are not strictly limited to the order of execution unless explicitly recited herein, and the steps may be executed in other orders. Moreover, at least a portion of the steps in fig. 5 may include a plurality of steps or stages that are not necessarily performed at the same time, but may be performed at different times, and the order of execution of the steps or stages is not necessarily sequential, but may be performed in rotation or alternatively with at least a portion of the steps or stages in other steps or other steps.
The text processing device provided by the embodiment of the application is described below, and the text processing device described below and the text processing method described above can be referred to correspondingly.
The present application also provides a gain adjusting device 600, which is applied to the control unit in the radio frequency read-write device according to any of the above embodiments, as shown in fig. 6, and the device includes:
the power acquisition module 601 is configured to acquire output power of the radio frequency amplification unit and reflected power of an antenna end of the coupler;
an antenna return loss calculation module 602, configured to calculate an antenna return loss according to the output power and the reflected power;
an attenuation value determining module 603, configured to determine a target attenuation value according to an antenna return loss, a coupling degree of the coupler, a maximum transmission power of the radio frequency transceiver, and a maximum carrier leakage;
the attenuation adjustment module 604 is configured to control the attenuation unit to adjust the link attenuation of the receiving link according to the target attenuation value.
In one embodiment, the gain adjustment device further comprises:
and the inventory control module is used for responding to the inventory instruction sent by the upper computer and controlling the radio frequency transceiver to transmit radio frequency signals until inventory is completed.
In one embodiment, the gain adjustment device further comprises:
and the alarm module is used for stopping inventory and sending an alarm when the return loss of the antenna is smaller than a preset threshold value.
In one embodiment, the present application also provides a storage medium having stored therein computer readable instructions which, when executed by one or more processors, cause the one or more processors to perform the steps of the gain adjustment method as set forth in any of the above embodiments.
Finally, it is further noted that relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.
As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," and/or the like, specify the presence of stated features, integers, steps, operations, elements, components, or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or groups thereof. Also, the term "and/or" as used in this specification includes any and all combinations of the associated listed items.
In the present specification, each embodiment is described in a progressive manner, and each embodiment focuses on the difference from other embodiments, and may be combined according to needs, and the same similar parts may be referred to each other.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (12)
1. A radio frequency read-write device, characterized in that the radio frequency read-write device comprises:
a radio frequency transceiver;
the radio frequency amplifying unit is used for amplifying and outputting radio frequency signals transmitted by the radio frequency transceiver;
the antenna end of the coupler is electrically connected with the antenna, the input end of the coupler is electrically connected with the radio frequency amplifying unit, the coupling end and the isolation end of the coupler are electrically connected with the radio frequency transceiver, and the coupler is used for transmitting the radio frequency signal output after being amplified by the radio frequency amplifying unit through the antenna and coupling the radio frequency signal to the radio frequency transceiver through the coupling end for carrier cancellation; the antenna is also used for outputting the radio frequency reflected signals received by the antenna to the radio frequency transceiver through the isolation degree end;
the attenuation unit is arranged between the isolation degree end of the coupler and the receiving end of the radio frequency transceiver and is used for providing link attenuation for the radio frequency reflection signal;
the control unit is used for detecting the output power of the radio frequency amplifying unit through the coupling end of the coupler, detecting the reflected power of the antenna end through the isolation end of the coupler, calculating the antenna return loss according to the output power and the reflected power, determining a target attenuation value according to the antenna return loss, the coupling degree of the coupler, the maximum transmitting power of the radio frequency transceiver and the maximum carrier leakage, and controlling the attenuation unit to adjust the link attenuation according to the target attenuation value.
2. The radio frequency read-write device according to claim 1, wherein the target attenuation value is inversely related to the antenna return loss.
3. The radio frequency read-write device according to claim 2, characterized in that the control unit comprises:
the detection circuit is respectively and electrically connected with the coupling end and the isolation degree end of the coupler and is used for collecting the output signal of the radio frequency amplifying unit and the receiving signal of the antenna end;
the controller is electrically connected with the detection circuit, and is used for determining the output power according to the output signal of the radio frequency amplifying unit acquired by the detection circuit, determining the reflected power according to the receiving signal of the antenna end acquired by the detection circuit, calculating the antenna return loss according to the output power and the reflected power, determining a target attenuation value according to the antenna return loss, the coupling degree of the coupler, the maximum transmitting power of the radio frequency transceiver and the maximum carrier leakage, and controlling the attenuation unit to adjust the link attenuation according to the target attenuation value.
4. A radio frequency read-write device according to claim 3, characterized in that the detection circuit comprises: the first detector, the second detector, the first sampling resistor and the second sampling resistor;
the input end of the first detector is electrically connected with the first end of the first sampling resistor, and the output end of the first detector is electrically connected with the controller;
the second end of the first sampling resistor is electrically connected with the coupling end of the coupler;
the input end of the second detector is electrically connected with the first end of the second sampling resistor, and the output end of the second detector is electrically connected with the controller;
and the second end of the second sampling resistor is electrically connected with the isolation degree end of the coupler.
5. The radio frequency read-write device according to claim 2, wherein the attenuation unit comprises:
the first end of the adjustable attenuator is electrically connected with the isolation degree end of the coupler, the second end of the adjustable attenuator is electrically connected with the radio frequency transceiver, and the control end of the adjustable attenuator is electrically connected with the control unit.
6. The radio frequency read-write device according to claim 2, wherein the attenuation unit comprises a first selection switch, a second selection switch and a plurality of fixed resistance attenuators;
the first end of the first selection switch is electrically connected with the isolation degree end of the coupler, the second ends of the first selection switch are respectively electrically connected with the first ends of the fixed resistance attenuators, and the control end of the first selection switch is electrically connected with the control unit;
the first ends of the second selection switches are respectively and electrically connected with the second ends of the fixed resistor attenuators, the second ends of the second selection switches are electrically connected with the radio-frequency transceiver, and the control ends of the second selection switches are electrically connected with the control unit;
the control unit is used for controlling the first selection switch and the second selection switch to select and conduct a passage where one fixed resistance attenuator is located according to the target attenuation value.
7. A gain adjustment method, applied to a control unit in a radio frequency read-write device according to any one of claims 1 to 6, the method comprising:
obtaining output power of a radio frequency amplifying unit and reflected power of an antenna end of a coupler;
calculating the return loss of the antenna according to the output power and the reflected power;
determining a target attenuation value according to the antenna return loss, the coupling degree of the coupler, the maximum transmitting power of the radio frequency transceiver and the maximum carrier leakage;
and controlling an attenuation unit to adjust the link attenuation of the receiving link according to the target attenuation value.
8. The method of gain adjustment according to claim 7, wherein the target attenuation value is inversely related to the antenna return loss.
9. The method of gain adjustment according to claim 7, further comprising, prior to the step of obtaining the output power of the rf amplifying unit and the reflected power at the antenna end of the coupler:
and responding to the inventory command sent by the upper computer, and controlling the radio frequency transceiver to emit a radio frequency signal until inventory is completed.
10. The method of gain adjustment according to claim 9, further comprising, after the step of calculating an antenna return loss from the output power and the reflected power:
and if the return loss of the antenna is smaller than a preset threshold value, stopping inventory and giving an alarm.
11. A gain adjustment device for use in a control unit in a radio frequency read-write apparatus according to any one of claims 1 to 6, the device comprising:
the power acquisition module is used for acquiring the output power of the radio frequency amplification unit and the reflected power of the antenna end of the coupler;
the antenna return loss calculation module is used for calculating the antenna return loss according to the output power and the reflected power;
the attenuation value determining module is used for determining a target attenuation value according to the antenna return loss, the coupling degree of the coupler, the maximum transmitting power of the radio frequency transceiver and the maximum carrier leakage;
and the attenuation adjusting module is used for controlling the attenuation unit to adjust the link attenuation of the receiving link according to the target attenuation value.
12. A storage medium, characterized by: the storage medium having stored therein computer readable instructions which, when executed by one or more processors, cause the one or more processors to perform the steps of the gain adjustment method of any of claims 7 to 10.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210542895.6A CN117134801A (en) | 2022-05-18 | 2022-05-18 | Radio frequency read-write equipment, gain adjusting method, device and storage medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210542895.6A CN117134801A (en) | 2022-05-18 | 2022-05-18 | Radio frequency read-write equipment, gain adjusting method, device and storage medium |
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| Publication Number | Publication Date |
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| CN117134801A true CN117134801A (en) | 2023-11-28 |
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| CN202210542895.6A Pending CN117134801A (en) | 2022-05-18 | 2022-05-18 | Radio frequency read-write equipment, gain adjusting method, device and storage medium |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN119255358A (en) * | 2024-09-18 | 2025-01-03 | 中国移动通信集团设计院有限公司 | Coupling device, system, uplink signal equalization method, equipment, medium and product |
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2022
- 2022-05-18 CN CN202210542895.6A patent/CN117134801A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN119255358A (en) * | 2024-09-18 | 2025-01-03 | 中国移动通信集团设计院有限公司 | Coupling device, system, uplink signal equalization method, equipment, medium and product |
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