WO2006007781A1

WO2006007781A1 - Heat sensitive attenuator and wireless transceiver

Info

Publication number: WO2006007781A1
Application number: PCT/CN2005/000996
Authority: WO
Inventors: Xuehai Chen
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2004-07-20
Filing date: 2005-07-07
Publication date: 2006-01-26
Also published as: CN1725632A; WO2006007781A8; CN100488039C

Abstract

The present invention relates to electronic field, and provides a heat sensitive attenuator and a wireless transceiver to enable a system to directly compensate radio frequency gain based on the temperature change and to reduce the cost of implementation effectively. This heat sensitive attenuator and the wireless transceiver may only use the heat sensitive attenuator which is composed of a NTC thermistor and other general resistors to compensate channel gain directly by using temperature change without a related temperature sensor, a memory element and an automatic gain control element.

Description

Thermal attenuator and wireless transceiver

TECHNICAL FIELD The present invention relates to the field of electronics, and more particularly to techniques for radio frequency gain temperature compensation of wireless transceivers.

Background technique

The RF gain amplifier in a wireless transceiver typically consists of a transistor amplifying circuit. Since the amplification factor of the transistor circuit changes with temperature, the RF channel gain of the entire wireless transceiver changes with temperature. In general, as the temperature increases, the channel gain will gradually decrease. Since the variation of the channel gain has a great influence on the transmission power and the receiving sensitivity, when the channel gain fluctuates too much with temperature, the quality of wireless communication will be seriously affected.

A control mechanism is currently used to control the automatic gain control circuit to compensate for variations in RF gain. For example: When the temperature increases, the gain of the RF channel in the wireless transceiver is reduced. At this time, the gain of the automatic gain control circuit can be increased by an appropriate control mechanism, and the gain of the automatic gain control circuit is increased and the RF is increased. The channel gains are reduced in equal value, thereby maintaining the overall channel gain substantially constant.

In the prior art, the control mechanism for the automatic gain control circuit is usually controlled by temperature look-up table. The specific implementation process is as follows. First, through the high and low temperature experiments, the RF channel gain data corresponding to different temperatures is collected and written into the storable device of the transceiver. When the transceiver is in normal operation, the current operating temperature is obtained by the temperature sensor, and the gain variation corresponding to the operating temperature is read from the storable device, and the voltage of the automatic gain control circuit is controlled by the gain variation. , thereby compensating for the channel gain. Those skilled in the art will appreciate that the temperature range stored in the storable device should be slightly greater than the actual operating temperature range, for example, if the transceiver operates over a temperature range of 0 to 40 degrees Celsius, then stored in a storable device. The minimum temperature in the medium should be less than 0 degrees and the maximum should be greater than 40 degrees. The above storable device may be a single random access memory.

In practical applications, the above solution has the following problems: The prior art requires an additional automatic gain control circuit, a memory device and a temperature sensor, which are costly to implement. Especially In storage devices, the capacity increases as the number of collection points increases, resulting in an increase in cost as the number of collection points increases. In addition, since it is necessary to collect data of gain variation with temperature in advance, it usually consumes a large amount of human resources, and eventually the product development cycle is too long.

Summary of the invention

In view of this, the main object of the present invention is to provide a thermal attenuator and a wireless transceiver, which enables the system to directly compensate for the RF gain according to the temperature change, and effectively reduce the realized cost.

To achieve the above object, the present invention provides a thermal attenuator comprising:

a first resistor having a first end connected to the input end and a second end connected to the output end; the second resistor having a first end connected to the first end of the first resistor and a second end grounded; the third resistor, a first end thereof is connected to the second end of the first resistor, and a second end is grounded; and

The first resistor is a thermistor.

And a fourth resistor connected in parallel with the first resistor, the first end of which is connected to the first end of the first resistor, and the second end is connected to the second end of the first resistor.

The fifth resistor further includes a first end connected to the first end of the second resistor, and a second end connected to the first end of the first resistor and the first end of the fourth resistor, respectively; or The first end is connected to the second end of the first resistor and the second end of the fourth resistor, respectively, and the second end is connected to the first end of the third resistor.

The invention also provides another thermal attenuator, comprising:

a sixth resistor, the first end of which is connected to the input end;

a seventh resistor, one end of which is connected to the second end of the sixth resistor, and the second end is connected to the output end;

An eighth resistor having a first end connected to the second end of the sixth resistor and a second end grounded; and

The sixth and seventh resistors are thermistors.

Among them, it also includes:

a ninth resistor connected in parallel with the sixth resistor, one end of which is connected to the first end of the sixth resistor, and the second end is connected to the second end of the sixth resistor; a tenth resistor connected in parallel with the seventh resistor, the first end of which is connected to the first end of the seventh resistor, and the second end is connected to the second end of the seventh resistor;

The eighth resistor has a first end connected to the second end of the ninth resistor.

Also including an eleventh resistor and a tenteenth resistor, wherein

The first end of the eleventh resistor is connected to the input end, and the second end is connected to the first end of the sixth resistor;

■ the first end of the twelfth resistor is connected to the second end of the seventh resistor, the second end thereof is connected to the output end, or the first end thereof is connected to the second end of the sixth resistor, and The second end thereof is connected to the first end of the seventh resistor;

Or

The first end of the eleventh resistor is connected to the second end of the seventh resistor, and the second end is connected to the first end of the eighth resistor;

a first end of the twelfth resistor is connected to the first end of the eighth resistor, a second end thereof is connected to the first end of the seventh resistor, or a first end thereof and the seventh resistor The second end is connected, and the second end thereof is connected to the output end.

In the above thermal attenuator, the thermistor employs a negative temperature coefficient thermistor or a positive temperature coefficient thermistor as needed.

The present invention also provides a wireless transceiver comprising at least one radio frequency device, further comprising at least one thermal attenuator employing a negative temperature coefficient thermistor, and wherein the thermal attenuator is connected in series with the radio frequency device . As used herein, in tandem, in a wireless transceiver employing a plurality of radio frequency devices and a plurality of thermal attenuators, the radio frequency devices are spaced in series with the thermal attenuator.

By comparison, it can be found that the technical solution of the present invention differs from the prior art in that only the NTC thermistor and other common resistors are used to constitute the thermal attenuator, and the channel gain is directly compensated by the change of temperature, without the relevant temperature sensor. , memory devices and automatic gain control devices.

The difference in this technical solution brings about a significant benefit, that is, without the need of temperature sensors, memory devices and automatic gain control devices, the design cost can be greatly reduced. There is no need to collect data during use, so it can effectively save human resources and speed up the product development cycle. BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a schematic structural view of a first Π type thermal attenuator circuit according to an embodiment of the present invention; FIG.

2 is a schematic view showing the structure of a second type of thermal attenuator circuit according to an embodiment of the present invention;

3 is a schematic view showing the structure of a third type of thermal attenuator circuit according to an embodiment of the present invention;

4 is a schematic structural view of a fourth 热敏 type thermal attenuator circuit according to an embodiment of the present invention;

Figure 5 is a block diagram showing the structure of a first type T thermistor according to another embodiment of the present invention;

6 is a schematic view showing the structure of a second type T thermal attenuator circuit according to another embodiment of the present invention;

Figure 7 is a block diagram showing the structure of three T-type thermal attenuators according to another real-time example of the present invention;

Figure 8 is a block diagram showing the structure of four T-type thermal attenuators according to another real-time example of the present invention;

9 is a schematic diagram showing a two-stage interval cascade structure of a radio frequency device and a thermal attenuator in a transceiver according to still another embodiment of the present invention;

Figure 10 is a schematic view showing a phase change scheme of a third type T thermal attenuator according to another real-time example of the present invention shown in Figure 7;

Figure 11 is a schematic illustration of a phase change scheme of a fourth T-type thermal attenuator in accordance with another real-time example of the present invention illustrated in Figure 8.

DETAILED DESCRIPTION OF THE INVENTION In order to make the objects, technical solutions and advantages of the present invention more comprehensible, the present invention will be further described in detail with reference to the accompanying drawings.

It is well known that the resistance of a negative temperature coefficient (Negat ive Temperature Coeff icient) is gradually decreased with increasing temperature, and the variation law satisfies the following relationship: B = ln (R / R0) / (l/Tl/T0) , where R is the resistance corresponding to the absolute temperature T, R0 The resistance value corresponding to the absolute temperature TO, B is the temperature constant of the NTC thermistor.

According to the principle of the present invention, by using the negative temperature characteristic of the NTC thermistor, a certain circuit form can be used to form a thermal attenuator, and if the attenuation of the thermal attenuator can be lowered as the temperature increases, It is possible to compensate for changes in channel gain. For example, when the temperature rises, the gain of the RF channel decreases, and the attenuation of the thermal attenuator also decreases. As long as the drop of the gain of the RF channel is the same as the attenuation of the thermal attenuator, the gain of the entire channel is basically not guaranteed. change.

The basic principle of automatic gain compensation using a NTC thermistor to form a thermal attenuator is briefly described above. Several basic circuit configurations constituting the thermal attenuator will be described in detail below.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view showing the structure of a first type of thermal attenuator circuit according to an embodiment of the present invention, as shown. The circuit diagram consists of three resistors: NTC thermistor 1, ordinary resistor 2, common resistor 3.

The first end of the NTC thermistor 1 is connected to the input end, and the second end is connected to the output end; the first end of the common resistor 2 is connected to the first end of the NTC thermistor 1, and the second end is grounded; One end is connected to the second end of the NTC thermistor 1, and the second end is grounded.

The above briefly describes the various components and connection relationships in the schematic diagram of the first type of thermistor. The working principle is described in detail below. The voltage at the input terminal is Vin, the input current is I in , the current flowing through the NTC thermistor 1 is II, the current flowing through the ordinary resistor 2 is 12, the current flowing through the ordinary resistor 3 is 13, and the voltage at the output terminal is Vout. First, assuming that the voltage Vin and the current I in at the input remain unchanged when the temperature changes, the current 12 flowing through the ordinary resistor 1 does not change. When the temperature rises, the resistance of the NTC thermistor 1 becomes smaller, causing the circuit II flowing through the NTC thermistor to increase, thereby causing the current 13 flowing through the ordinary resistor 3 to increase, eventually causing the output voltage Vout to rise, thus The gain calculation formula shows that as the temperature increases, the gain of the attenuator becomes larger. Therefore, by selecting the appropriate parameters of the NTC thermistor, the common resistor 2, and the ordinary resistor 3, the gain variation and the channel gain can be made. The amount of reduction is the same, so that the channel gain is kept substantially unchanged.

Since the characteristic impedance of the transmission line used in the RF circuit is generally 50 ohms, in order to ensure that the signal does not reflect during transmission, the characteristic impedance of the transmission line is required to match the impedance of the thermal attenuator, that is, the thermal attenuator input is required. The resistance seen at the end is also 50 ohms. In order to achieve the object, the second type shown in FIG. 1 according to an embodiment of the present invention may be employed. Schematic diagram of the structure of the type thermal attenuator. The circuit diagram consists of four resistors: NTC thermistor 1, normal resistor 2, normal resistor 3, normal resistor 4.

The first end of the NTC thermistor 1 is connected to the input end, and the second end is connected to the output end; the first end of the common resistor 2 is connected to the input end, and the second end is grounded; the first end of the common resistor 3 is connected to the output end, The two ends are grounded; the common resistor 4 and the NTC thermistor 1 are connected in parallel, the first end is connected to the input end and the first end of the NTC thermistor 1, the second end is connected to the output end and the second end of the NTC thermistor 1 .

The circuit works in a similar manner to the compensation principle of the first type of thermal attenuator circuit described above. Take the parameters of each resistor to achieve. For example: At 25 degrees Celsius, the attenuation type is 2. 2dB, and the respective resistors can be selected as follows: NTC thermistor 1 can be used in 0402 package structure, and its resistance at 22 degrees Celsius is 22 ohms. The constant B is 3100, and the operating temperature is -40 ~ 125 degrees Celsius. To ensure the symmetry of the circuit, the resistance of the common resistor 1 and the ordinary resistor 3 are both selected to be 430 ohms, and the resistance of the common resistor 4 is selected to be 51 ohms. When the temperature changes, the input impedance of the above thermal attenuator changes around 50 ohms, which basically meets the matching requirements.

In order to achieve the matching of the transmission line and the thermal attenuator, a schematic diagram of the structure of the third type of thermistor circuit according to an embodiment of the present invention shown in Fig. 3 can also be selected, as shown. The circuit structure is composed of five resistors: NTC thermistor 1, ordinary resistor 2, common resistor 3, normal resistance 4, common resistor 5.

The first end of the NTC thermistor 1 is connected to the second end of the common resistor 5, and the second end is connected to the output end; the first end of the common resistor 2 is connected to the input end, and the second end thereof is grounded; One end is connected to the output end, and the second end is grounded; the first end of the common resistor 4 is connected to the first end of the NTC thermistor 1, and the second end is connected to the output end; the first end of the common resistor 5 is connected to the input end, The second end is connected to the first end of the NTC thermistor 1 and the first end of the common resistor 4. The compensation principle of this circuit is similar to the compensation principle of the first type of thermal attenuator described above.

Similarly, as a modification of Fig. 3, Fig. 4 is a schematic view showing the structure of a circuit of four types of 热敏 type thermal attenuators according to an embodiment of the present invention, as shown. The circuit structure is also composed of five resistors: NTC thermistor 1, ordinary resistor 2, common resistor 3, ordinary resistor 4, ordinary resistor 5.

The first end of the NTC thermistor 1 is connected to the input end, and the second end of the NTC thermistor 1 is connected to the common resistor. The first end of the common resistor 2 is connected to the input end, and the second end thereof is grounded; the first end of the common resistor 3 is connected to the output end, and the second end thereof is grounded; the first end of the common resistor 4 is connected to the NTC heat The first end of the varistor 1 has a second end connected to the first end of the common resistor 5; the first end of the common resistor 5 is connected to the second end of the NTC thermistor 1 and the second end of the common resistor 4, the second end thereof The end is connected to the output. The compensation principle of the circuit is similar to the compensation principle of the first type of thermal attenuator circuit described above.

The various basic circuit structures for compensating the channel gain of the 热敏-type thermal attenuator and its compensation principle are described above. The following is a basic circuit for the principle of the present invention based on the principle of the present invention. Compensation circuit structure and compensation principle.

The first is to introduce the most simple T-type circuit structure. Fig. 5 is a block diagram showing the structure of a first type T thermal attenuator circuit according to an embodiment of the present invention. The structure is mainly composed of three resistors: NTC thermistor 6, NTC thermistor 7, and common resistor 8.

The first end of the NTC thermistor 6 is connected to the input end, and the second end is connected to the first end of the NTC thermistor ;; the first end of the NTC thermistor 7 is connected to the second end of the NTC thermistor 6, The second end is connected to the output end; the first end of the common resistor 8 is connected to the second end of the NTC thermistor 6 and the first end of the NTC thermistor 7, and the second end thereof is grounded.

The upper cylinder describes the connection relationship of the various components of the T-type thermal attenuator circuit. The temperature compensation principle will be described in detail below. Assuming that the voltage at the input is Vin, the input current is I in; the circuit flowing through the NTC thermistor 6 is 16, the current flowing through the NTC thermistor 7 is 17, and the current flowing through the normal resistor 8 is 18. Assuming that the input voltage V in and the input current I in remain unchanged, since the current 17 flowing through the NTC thermistor 7 is the input current, 17 remains unchanged. As the temperature becomes higher, the resistance value of the NTC thermistor 6 decreases. According to Ohm's law, the voltage across the NTC thermistor 6 decreases, so that the voltage applied to the first end of the ordinary resistor 8 increases, that is, flows through The current 18 of the ordinary resistor 8 becomes large. According to Kirchhoff's current law, the current 16 flowing through the NTC thermistor 6 does not change, and the current 18 flowing through the ordinary resistor 8 becomes larger, so that the current 17 flowing through the NTC thermistor 7 is reduced due to the NTC heat. The resistance of the varistor 7 is also reduced with temperature, so the voltage across the NTC thermistor 7 is also lowered. Since the voltage at the first end of the NTC thermistor 7 rises and the voltage drop across the NTC thermistor 7 decreases, the second end of the NTC thermistor, that is, the voltage Vout at the output terminal increases. Therefore, the gain calculation formula can be seen As the temperature increases, the gain of the circuit structure gradually increases, so that the channel gain can be effectively compensated.

In order to achieve the matching of the transmission line characteristic impedance and the attenuator input impedance, it can be implemented by any of the following three circuits.

Figure 6 is a schematic view showing the structure of a second type T thermal attenuator circuit, as shown in the figure, in accordance with one embodiment of the present invention. The circuit diagram consists of five resistors: NTC thermistor 6, NTC thermistor 7, common resistor 8, common resistor 9, common resistor 1 0.

The first end of the NTC thermistor 6 is connected to the input end, and the second end is connected to the first end of the NTC thermistor 7; the first end of the NTC thermistor 7 is connected to the second end of the NTC thermistor 6, The second end is connected to the output end; the first end of the common resistor 8 is connected to the second end of the NTC thermistor 6 and the first end of the NTC thermistor 7, the second end of which is grounded; the first end of the common resistor 9 is connected The input end and the first end of the NTC thermistor 6, the second end of which is connected to the second end of the NTC thermistor 6 and the first end of the common resistor 8; the first end of the common resistor 10 is connected to the NTC thermistor 7 The first end and the first end of the common resistor 8 have a second end connected to the output end and a second end of the NTC thermistor 。. The compensation principle of this circuit is similar to the compensation principle of the first type T thermal attenuator described above.

Fig. 7 is a schematic view showing the structure of a third type T thermistor according to an embodiment of the present invention, as shown. The circuit diagram consists of 7 resistors: NTC thermistor 6, NTC thermistor 7, ordinary resistor 8, ordinary resistor 9, ordinary resistor 10, ordinary resistor 11, ordinary resistor 12.

The first end of the NTC thermistor 6 is connected to the second end of the common resistor 11, and the second end is connected to the first end of the NTC thermistor 7; the first end of the NTC thermistor 7 is connected to the NTC thermistor 6 The second end of the second resistor is connected to the first end of the common resistor 12; the first end of the common resistor 8 is connected to the second end of the NTC thermistor 6 and the first end of the NTC thermistor 7, and the second end is grounded. The common resistor 9 is connected in parallel with the NTC thermistor 6, the first end of which is connected to the first end of the NTC thermistor 6, the second end is connected to the second end of the NTC thermistor 6; the common resistor 10 and the NTC thermistor 7 In parallel, the first end is connected to the first end of the NTC thermistor 7, and the second end is connected to the second end of the NTC thermistor 7; the first end of the common resistor 11 is connected to the input end, and the second end is connected to the NTC thermal a first end of the resistor 6 and a first end of the common resistor 9; a first end of the common resistor 12 is connected to the second end of the NTC thermistor 7 and the second end of the common resistor 10, and the second end thereof is connected Output. The compensation principle is similar to the compensation principle of the first type T thermal attenuator. It should be noted that, in this embodiment, there may be another phase change scheme, that is, as shown in FIG. 8, the first end of the common resistor 12 is connected to the second end of the NTC thermistor 6 and the common resistor 9, and the common The first end of the resistor 8 has its second end connected to the NTC thermistor 7 and the first end of the conventional resistor 10. The NTC thermistor Ί and the second end of the common resistor 10 are connected to the output. The compensation principle is similar to that described above.

Figure 8 is a schematic view showing the structure of a fourth type T thermal attenuator circuit, as shown in the figure, in accordance with one embodiment of the present invention. It is a modified structure of Fig. 7, and the circuit diagram is also composed of 7 resistors: NTC thermistor 6, NTC thermistor 7, common resistor 8, common resistor 9, common resistor 10, normal resistance 11, common resistor 12.

The first end of the NTC thermistor 6 is connected to the input end, and the second end is connected to the first end of the common resistor 11; the first end of the NTC thermistor 7 is connected to the second end of the common resistor 12, and the second end thereof Connecting the output end; the first end of the common resistor 8 is connected to the second end of the common resistor 11 and the first end of the common resistor 12, and the second end thereof is grounded; the common resistor 9 is connected in parallel with the NTC thermistor 6, and the first end is connected The first end of the NTC thermistor 6 is connected to the second end of the TC thermistor 6; the common resistor 10 is connected in parallel with the NTC thermistor 7, and the first end thereof is connected to the first end of the NTC thermistor 7, The second end is connected to the second end of the NTC thermistor; the first end of the common resistor 11 is connected to the second end of the NTC thermistor 6 and the second end of the common resistor 10, and the second end is connected to the second end of the common resistor 12 One end; the first end of the common resistor 12 is connected to the second end of the common resistor 11, and the second end is connected to the first end of the NTC thermistor 7 and the first end of the common resistor 10. The compensation principle of this circuit is similar to that of the first type T thermal attenuator. It should be noted that, in this embodiment, there may be another phase change scheme, that is, as shown in FIG. 11, the first ends of the NTC thermistor 7 and the common resistor 10 are connected to the second end of the common resistor 11 and The first end of the resistor 8 connects the second ends of the NTC thermistor 7 and the common resistor 10 to the first end of the common resistor 12, and connects the second end of the common resistor 12 to the output terminal. The compensation principle is similar to that described above.

The thermistor used in the thermal attenuator described above is an NTC thermistor, but it should be noted that, as the attenuator is used in a different manner, an attenuator having a positive temperature characteristic may also be required in practice. A thermistor requires a positive temperature coefficient thermistor. In an electronic device using the thermal attenuator of the NTC thermistor provided by the present invention, the RF channel may be involved in the RF channel, and the gain of each RF device may vary with temperature, if only one thermal attenuation is used. The device is temperature compensated for all devices in the entire circuit, and the design of the thermal attenuator will be very complicated or even impossible. To solve this problem, the circuit can be arranged in a multi-stage thermal attenuator and RF device spacing cascade.

9 is a schematic diagram showing a two-stage interval cascade structure of a radio frequency device and a thermal attenuator in a transceiver according to an embodiment of the present invention, the thermal attenuator adopting an NTC thermistor, as shown in the figure, with multiple intervals The schematic diagram of the cascade is similar. The circuit structure is composed of a radio frequency device 13, a radio frequency device 14, a thermal attenuator 15, and a thermal attenuator 16.

The first end of the RF device 13 is connected to the input end, and the second end is connected to the first end of the thermal attenuator 15; the first end of the thermal attenuator 15 is connected to the second end of the RF device 13, and the second end thereof Connecting the first end of the radio frequency device 14; the first end of the radio frequency device 14 is connected to the second end of the thermal attenuator 15, the second end of which is connected to the first end of the thermal attenuator 16; the first end of the thermal attenuator 16 The end is connected to the second end of the RF device 14, and the second end is connected to the output end. Those skilled in the art will appreciate that the circuit structure employed by the thermal attenuators 15, 16 can be any of the above Figures 1 through 8. The RF devices 13, 14 can be mixers, RF transistor amplifiers or filters.

Due to the cascading of RF devices and thermal attenuators, each RF device is compensated by a cascading thermal attenuator, since the gain variation of a single RF device is relative to the sum of the gain variations of all RF devices across the circuit. It is not very aggressive, so it is easy to design a thermal attenuator that is cascaded with the RF device.

In addition, as the operating frequency continues to increase, the parasitic parameters of the thermistor become more and more obvious, especially for the frequency band above 1 GHz, the parasitic parameters of the thermistor have significant influence, and the temperature compensation effect is not ideal, so this The technical solution of the invention is generally applicable to the compensation of the intermediate frequency circuit in the RF circuit below 1 GHz or in the transceiver. If the present invention is used for a transceiver that transmits and receives frequencies higher than 1 GHz, it can also be used in circuits whose internal frequency is lower than 1 GHz, such as in the intermediate frequency portion.

Although the invention has been illustrated and described with reference to certain preferred embodiments of the invention It will be apparent to those skilled in the art that various changes may be made in the form and the details of the present invention without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

Rights request

A thermal attenuator, comprising:

The first resistor is a thermistor.

2. The thermal attenuator according to claim 1, further comprising a fourth resistor connected in parallel with the first resistor, the first end of which is connected to the first end of the first resistor, and the second The end is connected to the second end of the first resistor.

3. The thermal attenuator according to claim 1, further comprising a fifth resistor, wherein the first end is connected to the first end of the second resistor, and the second end is respectively connected to the first resistor a first end, and a first end of the fourth resistor; or

The first end is connected to the second end of the first resistor and the second end of the fourth resistor, respectively, and the second end is connected to the first end of the third resistor.

The thermal attenuator according to claim 1, 2 or 3, wherein the thermistor is a negative temperature coefficient thermistor.

5. A thermal attenuator, comprising:

a sixth resistor, the first end of which is connected to the input end;

a seventh resistor, the first end of which is connected to the second end of the sixth resistor, and the second end is connected to the output end;

An eighth resistor having a first end connected to the second end of the sixth resistor and a second end grounded;

The sixth and seventh resistors are thermistors.

6. The thermal attenuator according to claim 5, further comprising: a ninth resistor connected in parallel with the sixth resistor, the first end of which is connected to the first end of the sixth resistor, a second end connected to the second end of the sixth resistor;

a tenth resistor connected in parallel with the seventh resistor, the first end of which is connected to the first end of the seventh resistor, and the second end is connected to the second end of the seventh resistor; The eighth resistor has a first end connected to the second end of the ninth resistor.

7. The thermal attenuator according to claim 6, further comprising an eleventh resistor and a twelfth resistor, wherein

a first end of the twelfth resistor is connected to the second end of the seventh resistor, and a second end thereof is connected to the output end, or a first end thereof is connected to the second end of the sixth resistor, and The second end thereof is connected to the first end of the seventh resistor;

Or

The first end of the twelfth resistor is connected to the first end of the eighth resistor, and the second end thereof is connected to the first end of the seventh resistor, or the first end thereof and the seventh resistor The second end is connected, and the second end is connected to the output end.

The thermal attenuator according to claim 4, 5, 6 or 7, wherein the thermistor is a negative temperature coefficient thermistor.

A wireless transceiver comprising at least one radio frequency device, characterized by further comprising at least one thermal attenuator according to claim 4 or 8, and said thermal attenuator and said radio frequency device Connected in series.

10. The wireless transceiver of claim 9, wherein the radio frequency device is spaced in series with the thermal attenuator.