CN103516366A - Input signal intensity indicator and indicating method - Google Patents

Abstract

The invention discloses an input signal strength indicator and an indicating method. The input signal strength indicator can quantize the amplitude of the input signal and output a binary digital signal corresponding to the input signal strength without using a dedicated module. A digital converter is used to convert the analog signal to a digital signal, so there is no need to measure the relationship between the input signal amplitude and the output voltage in advance, which not only reduces the cost and structural complexity of the input signal indicator, but also simplifies the input signal. The entire processing flow of the intensity indicator.

Description

Input signal strength indicator and how to indicate it

technical field

The invention relates to the technical field of electronic circuits, and more specifically relates to an input signal strength indicator and an indicating method.

Background technique

The received signal strength indicator is a common circuit module in radio frequency receivers, which can indicate the strength of the received signal by converting the amplitude of the input signal into a voltage or current signal. The output of the circuit in the traditional RSSI is an analog voltage or current signal, so an analog-to-digital converter is needed to convert the analog voltage or current into a binary value that can be recognized by the digital circuit, so as to further perform digital baseband processing.

However, adding an analog-to-digital converter in the RSSI not only increases the cost and structural complexity of the entire RSSI, but also must be pre-tested to obtain the ratio between the output signal amplitude and the output voltage of the RSSI. Relationship, so as to facilitate the subsequent processing process of deriving the amplitude of the input signal, which makes the entire processing process of the RSSI relatively cumbersome and complicated.

Contents of the invention

In view of this, the present invention provides an input signal strength indicator and an indicating method to overcome the cost and complex structure of the entire RSSI in the prior art due to the existence of an analog-to-digital converter in the RSSI And the whole process is cumbersome and complicated.

To achieve the above object, the present invention provides the following technical solutions:

An input signal strength indicator comprising:

An analog signal conversion circuit, configured to convert the input signal into a corresponding analog current signal; the analog current signal is linearly negatively correlated with the amplitude value of the input signal;

A low-pass filter circuit, configured to perform low-pass filter processing on the analog current signal and generate an analog voltage signal; parameters of the low-pass filter circuit are controlled by the first output value of the conversion control circuit;

A voltage comparison circuit, used to compare the analog voltage signal with the threshold voltage generated by the threshold voltage generation circuit, and output the comparison result;

a threshold voltage generating circuit, configured to generate a high threshold voltage value and a low threshold voltage value; the voltage interval determined by the high threshold voltage value and the low threshold voltage value is controlled by the second output value of the conversion control circuit;

The conversion control circuit is used for controlling the output of the first output value or the second output value according to the voltage comparison result of the voltage comparison circuit, and outputting a digital indication signal corresponding to the amplitude of the input signal.

Optionally, the analog signal conversion circuit includes N limiters and N+1 rectifiers; wherein the limiters are used to amplify the input signal, and the rectifiers are used to convert AC signals into DC Signals, the DC signals output by each rectifier are summarized to generate an analog current signal; the N is a positive integer.

Optionally, one end of the low-pass filter circuit is connected to the output end of the analog signal conversion circuit, and the other end is grounded, including a capacitor and a programmable resistor arranged in parallel.

Optionally, the voltage comparison circuit includes a first comparison circuit and a second comparison circuit, the first comparison circuit is used to compare the analog voltage signal and the high voltage threshold value, and the second comparison circuit is used to compare the Describe the analog voltage signal and the low voltage threshold.

Optionally, the threshold voltage generation circuit includes a programmable current source and two voltage dividing resistors arranged in series; the programmable current source is controlled by the second output value of the conversion control circuit.

Optionally, also include:

A clock circuit connected to the conversion control circuit is used to provide a clock signal for the conversion control circuit.

Optionally, also include:

One end is connected to the output end of the analog signal conversion circuit, and the other end is connected to the programmable current mirror of the conversion control circuit, and the programmable current mirror is controlled by the third output value of the conversion control circuit.

A method for indicating input signal strength, applied to the above-mentioned input signal strength indicator, comprising:

When the amplitude of the input signal is zero, the conversion control circuit sets the second output value to a maximum value;

The conversion control circuit performs a self-calibration process;

Execute the input signal strength measurement process;

Output a digital indicator signal corresponding to the input signal amplitude.

Optionally, the self-calibration process includes: when the analog voltage signal is greater than the high value of the threshold voltage, the conversion control circuit reduces the first output value, and controls to reduce the resistance value of the low-pass filter circuit to reduce the The value of the analog voltage signal; when the analog voltage signal is less than the threshold voltage low value, the conversion control circuit increases the first output value, and controls to increase the resistance value of the low-pass filter circuit to increase increasing the value of the analog voltage signal;

The self-calibration process is repeatedly executed until the value of the analog voltage signal is within a voltage range determined by the high threshold voltage value and the low threshold voltage value.

Optionally, the self-calibration process includes: when the analog voltage signal is greater than the high value of the threshold voltage, the conversion control circuit reduces the third output value, and controls to reduce the analog current signal to reduce the analog voltage signal value; when the analog voltage signal is less than the threshold voltage low value, the conversion control circuit increases the third output value, and controls the increase of the analog current signal to increase the value of the analog voltage signal;

The self-calibration process is repeatedly executed until the value of the analog voltage signal is within a voltage range determined by the high threshold voltage value and the low threshold voltage value.

Optionally, the input signal strength measurement process includes:

The conversion control circuit monitors the analog voltage signal through a voltage comparison circuit. When the analog voltage signal is lower than the lowest threshold voltage value, the conversion control circuit reduces the second output value, and controls to reduce the programmable current source. current to reduce the threshold voltage; when the analog voltage signal is greater than the high value of the threshold voltage, the conversion control circuit increases the second output value, and controls to increase the current of the programmable current source to increase the threshold voltage ; until the value of the analog voltage signal is within the voltage range determined by the high threshold voltage value and the low threshold voltage value.

Optionally, before outputting the digital indication signal corresponding to the amplitude of the input signal, it also includes:

The conversion control circuit detects whether the analog voltage signal is in the voltage range determined by the high threshold voltage and the low threshold voltage in the M clock cycles, and if so, enters the step of outputting a digital indication signal corresponding to the input signal amplitude; M is a positive integer.

It can be seen from the above technical solutions that, compared with the prior art, the embodiment of the present invention discloses an input signal strength indicator and an indicating method, and the input signal strength indicator can quantize the amplitude of the input signal and output The binary digital signal corresponding to the input signal strength does not require a dedicated analog-to-digital converter to convert the analog signal to a digital signal, so there is no need to measure the relationship between the input signal amplitude and the output voltage in advance, which not only reduces the input The cost and structural complexity of the signal indicator are reduced, and the entire processing flow of the input signal strength indicator is also simplified.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only It is an embodiment of the present invention, and those skilled in the art can also obtain other drawings according to the provided drawings without creative work.

FIG. 1 is a schematic diagram of a circuit structure of an input signal strength indicator disclosed in an embodiment of the present invention;

Fig. 2 is a circuit structure diagram of an analog signal conversion circuit disclosed in an embodiment of the present invention;

3 is a circuit structural diagram of a low-pass filter circuit disclosed in an embodiment of the present invention;

FIG. 4 is a circuit structural diagram of a voltage comparison circuit disclosed in an embodiment of the present invention;

FIG. 5 is a circuit structure diagram of a threshold voltage generating circuit disclosed in an embodiment of the present invention;

Fig. 6 is a schematic circuit structure diagram of another input signal strength indicator disclosed in an embodiment of the present invention;

7 is a circuit structure diagram of a programmable current mirror disclosed in an embodiment of the present invention;

Fig. 8 is a flowchart of an input signal strength indicating method disclosed in an embodiment of the present invention;

FIG. 9 is a schematic diagram of a self-calibration process disclosed by an embodiment of the present invention.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Fig. 1 is a schematic diagram of a circuit structure of an input signal strength indicator disclosed in an embodiment of the present invention. Referring to Fig. 1, the input signal strength indicator may include:

An analog signal conversion circuit, configured to convert the input signal into a corresponding analog current signal I _RSSI ; the analog current signal I _RSSI is linearly negatively correlated with the amplitude value of the input signal;

In a schematic example, the specific structure of the analog signal conversion circuit can be referred to FIG. 2. FIG. 2 is a circuit structure diagram of an analog signal conversion circuit disclosed in an embodiment of the present invention. As shown in FIG. 2, the analog signal The conversion circuit may include N limiters and N+1 rectifiers. In FIG. 2 , 4 limiters and 5 rectifiers are taken as an example. Wherein, the limiter is used to amplify the input signal; the rectifier is used to amplify the input signal, and the DC signals output by each rectifier are aggregated to generate an analog current signal I _RSSI . Wherein said N is a positive integer.

A low-pass filter circuit, configured to perform low-pass filter processing on the analog current signal I _RSSI and generate an analog voltage signal V _RSSI ;

The parameters of the low pass filter circuit are controlled by the first output value of the conversion control circuit. One end of the low-pass filter circuit is connected to the output end of the analog signal conversion circuit, and the other end is grounded to generate an analog voltage signal V _RSSI corresponding to the analog current signal I _RSSI .

In a schematic example, the specific structure of the low-pass filter circuit can be referred to FIG. 3, which is a circuit structure diagram of a low-pass filter circuit disclosed in an embodiment of the present invention. As shown in FIG. The filter may comprise a capacitor C and a programmable resistor R1 arranged in parallel. Since one end of the low-pass filter is grounded, the value of the analog voltage signal V _RSSI can be changed by changing the resistance of the programmable resistor R1 .

A voltage comparison circuit, used to compare the analog voltage signal V _RSSI with the threshold voltage generated by the threshold voltage generation circuit, and output the comparison result;

The specific structure of the voltage comparison circuit can be referred to FIG. 4. FIG. 4 is a circuit structure diagram of the voltage comparison circuit disclosed in the embodiment of the present invention. As shown in FIG. 4, the voltage comparison circuit can include a first comparison circuit 401 and a second comparison circuit 401. Two comparison circuits 402, the first comparison circuit 401 is used for comparing the analog voltage signal V _RSSI and the high threshold voltage Vh, and the second comparison circuit 402 is used for comparing the analog voltage signal V _RSSI and the low threshold voltage Value Vl. Both the comparison results of the first comparison circuit 401 and the second comparison circuit 402 are output to the conversion control circuit.

Threshold voltage generation circuit, used to generate threshold voltage high value Vh and threshold voltage low value Vl;

The threshold voltage high value Vh and the threshold voltage low value Vl are controlled by the second output value of the switching control circuit.

The specific structure of the threshold voltage generating circuit can be referred to FIG. 5, which is a circuit structure diagram of the threshold voltage generating circuit disclosed in the embodiment of the present invention. As shown in FIG. 5, the threshold voltage generating circuit can include: programmable current source and two voltage dividing resistors R2 and R3 arranged in series; the programmable current source is controlled by the second output value of the conversion control circuit.

Specifically, the second output value of the conversion control circuit can directly control the output current of the programmable current source, and the two voltage dividing resistors are set in series, and the two ends of the structure composed of the two voltage dividing resistors are respectively connected to As for the programmable circuit source and the ground, since the resistance values of the two voltage dividing resistors are determined, when the output currents of the programmable current source are different, the voltages divided by the two voltage dividing resistors are different, which can be The sum of the voltages obtained by the two voltage-dividing resistors is used as the high threshold voltage Vh, and the voltage obtained by the voltage-dividing resistor close to the ground is used as the low threshold voltage Vl. It should be noted that the high threshold voltage value Vh and the low threshold voltage value Vl are not a set of fixed values, and the high threshold voltage value Vh and the low threshold voltage value Vl can vary with the programmable current source The magnitude of the output current changes, and the magnitude of the output current of the programmable current source is directly controlled by the second output value output by the conversion control circuit.

The conversion control circuit is used for controlling the output of the first output value or the second output value according to the voltage comparison result of the voltage comparison circuit, and outputting a digital indication signal corresponding to the amplitude of the input signal.

The input signal strength indicator can have different modes of operation, such as a self-calibration mode and a mode for measuring input signal lightness. In different working modes, the conversion control circuit can indirectly adjust the resistance value of the low-pass filter circuit or the threshold voltage generated by the threshold voltage generation circuit according to the comparison result generated by the voltage comparison circuit.

Fig. 6 is a schematic diagram of the circuit structure of another input signal strength indicator disclosed in an embodiment of the present invention. Fig. 6 shows the specific circuit structure of each part of the input signal strength indicator. The above input signal can be understood in conjunction with Fig. 6 The circuit structure of each part of the indicator and its connection relationship.

In this embodiment, the input signal strength indicator can quantize the magnitude of the input signal, and output a binary digital signal corresponding to the strength of the input signal, without requiring a dedicated analog-to-digital converter to convert the analog signal into a digital signal. Therefore, there is no need to measure the relationship between the input signal amplitude and the output voltage in advance, which not only reduces the cost and structural complexity of the input signal indicator, but also simplifies the entire processing flow of the input signal strength indicator.

In other embodiments, in addition to the various circuit structures disclosed in the above embodiments, the input signal strength indicator may also include a clock circuit connected to the conversion control circuit for providing a clock signal for the conversion control circuit , so that the conversion control circuit works regularly under the drive of the clock circuit.

Further, in other embodiments, the received signal strength indicator may also include a programmable current mirror with one end connected to the output end of the analog signal conversion circuit and one end connected to the conversion control circuit. The programming current mirror is controlled by the third output value of the conversion control circuit. Specifically, the value of the analog current signal can be changed by changing the value of D (3:0). A schematic structural diagram of the programmable current mirror can be referred to FIG. 7 , which is a circuit structural diagram of the programmable current mirror disclosed in an embodiment of the present invention. Among them, D0-D3 in the upper part of Fig. 7 is a switch circuit, and the lower part is a current mirror circuit structure; I _RSSI is an analog current signal, and I _RSSI-1 is the third output value output by the conversion control circuit.

${\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; RSSI</span>}<span\; class="notranslate">\; \_</span>\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; RSSI</span>}}}{\mathrm{<span\; class="notranslate">\; K</span>}}\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}{\mathrm{<span\; class="notranslate">\; 2</span>}}^{\mathrm{<span\; class="notranslate">\; no</span>}}\mathrm{<span\; class="notranslate">\; D.</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; .</span>$

Fig. 8 is a flowchart of the input signal strength indication method disclosed in the embodiment of the present invention, the input signal strength indication method is applied to the input signal strength indicator disclosed in the above embodiment, and the input signal strength indicator includes analog signal conversion circuit, low-pass filter circuit, voltage comparison circuit, threshold voltage generation circuit and conversion control circuit. Referring to Figure 8, the input signal strength indication method may include:

Step 801: When the amplitude of the input signal is zero, the conversion control circuit sets the second output value to the maximum value;

When the input signal strength indicator starts to work, the input amplitude of the input signal is zero, because the analog current signal I _RSSI is linearly negatively correlated with the amplitude value of the input signal, therefore, the analog current signal I _RSSI at this time and the analog The voltage signal V _RSSI will be maximum. At this time, it is necessary to first set the second output value to the maximum value, and then execute the self-calibration process. However, if the second output value is set to the maximum value, the high threshold voltage value Vh generated at this time should be the maximum threshold voltage that can be generated by the threshold voltage generation circuit.

Step 802: the conversion control circuit performs a self-calibration process;

In a schematic example, the specific steps of the self-calibration process can be referred to FIG. 9, which is a schematic diagram of the self-calibration process disclosed in the embodiment of the present invention. As shown in FIG. 9, it may include:

Step 901: judging whether the analog voltage signal V _RSSI is greater than the high threshold voltage Vh, if yes, go to step 902, if not, go to step 905;

Step 902: the conversion control circuit reduces the first output value, and controls to reduce the resistance value of the low-pass filter circuit to reduce the value of the analog voltage signal V _RSSI ; enter step 905;

Step 903: judging whether the analog voltage signal V _RSSI is smaller than the low threshold voltage V1, if yes, go to step 904, if not, go to step 905;

Step 904: the conversion control circuit increases the first output value, and controls to increase the resistance value of the low-pass filter circuit to increase the value of the analog voltage signal V _RSSI ; enter step 905;

Step 905: judging whether the value of the analog voltage signal V _RSSI is within the voltage range determined by the high threshold voltage Vh and the low threshold voltage V1, if yes, proceed to step 906, if not, proceed to step 901 or step 903;

Step 906: end.

In summary, it can be seen that the self-calibration process is to ensure that the maximum value of the analog voltage signal V _RSSI is between the high threshold voltage Vh and the low threshold voltage Vl, so that the input The effectiveness of signal strength measurement avoids the influence of process deviation and temperature on the measurement results.

In case the input signal strength indicator comprises a programmable current mirror, the analog current signal _IRSSI can also be changed by the programmable current mirror, so as to perform self-calibration. In this case, the resistance value in the low-pass filter may not change, and the self-calibration process includes: when the analog voltage signal V _RSSI is greater than the threshold voltage high value Vh, the conversion control circuit reduces the third output value, controlling to reduce the analog current signal I _RSSI to reduce the value of the analog voltage signal V _RSSI ; when the analog voltage signal V _RSSI is less than the threshold voltage low value V1, the conversion control circuit increases the third Output value, control to increase the analog current signal I _RSSI to increase the value of the analog voltage signal V _RSSI ; repeat the self-calibration process until the value of the analog voltage signal V _RSSI is located at the threshold voltage high value Vh And within the voltage range determined by the threshold voltage low value Vl.

After step 802, go to step 803.

Step 803: Execute the input signal strength measurement process;

Wherein, the signal strength measurement process may include: the conversion control circuit monitors the analog voltage signal V _RSSI through a voltage comparison circuit, and when the analog voltage signal V _RSSI is smaller than the threshold voltage low value V1, the conversion control circuit decreases The second output value is controlled to reduce the current of the programmable current source to reduce the threshold voltage; when the analog voltage signal V _RSSI is greater than the threshold voltage high value Vh, the conversion control circuit increases the second output value, control to increase the current of the programmable current source to increase the threshold voltage; until the value of the analog voltage signal V _RSSI is within the voltage range determined by the high threshold voltage Vh and the low threshold voltage Vl.

The specific process of the input signal strength measurement process is similar to the specific execution process of the above self-calibration process, except that the output value controlled by the conversion control circuit is different.

1) The conversion control circuit controls and adjusts the output current of the programmable current source through the second output value, and the change of the output current of the programmable current source can be linear stepping, that is, the conversion control circuit only controls the output current of the programmable current source each time. Add 1 or subtract 1 to the second output value. Of course, the conversion control circuit can also control and adjust the output current of the programmable current source through other algorithms through the second output value, for example, using a binary weight algorithm. The steps for implementing the binary weight algorithm can be as follows:

Set the N-1th bit of the second output value D _CI to 1, and the other bits to 0, that is, D _CI =2 ^N-1 , use a voltage comparison circuit to judge, if V _RSSI <V _TL , then the N-th 1 bit is set to 0; when V _RSSI >V _TH is detected, the N-1th bit is set to 1;

Set the N-2th bit of D _CI to 1, that is, D _CI =D _CI +2 ^N-2 , use the voltage comparison circuit to judge, if V _RSSI <V _TL , set the N-2th bit to 0; When it is detected that V _RSSI >V _TH , the N-2th bit is set to 1.

Follow the above steps to determine the values of the remaining bits of D _CI in turn. When the value of the 0th bit is determined, the measurement ends, and D _out is updated to 2 ^N –1 – D _CI .

Step 804: Output a digital indication signal corresponding to the amplitude of the input signal.

There is a one-to-one correspondence between the digital indication signal output by the conversion control circuit and the input signal amplitude, or in other words, there is a one-to-one correspondence between the input signal amplitude and the voltage interval determined by the high threshold voltage Vh and the low threshold voltage Vl. When the signal amplitude changes, it will inevitably go through the input signal strength measurement process described in step 803 .

Based on the above steps, it can be seen that when the input signal amplitude is 0, the analog current signal I _RSSI is the largest, and the analog voltage signal V _RSSI is at the maximum value of the range, the second output value of the conversion control circuit will be set to The maximum value is 2 ^N -1, and the digital indicator signal output by the conversion control circuit at this moment is 0; when the input signal amplitude reaches or exceeds the upper limit of the range of the input signal strength indicator, the limit in the analog signal conversion circuit Amplifiers are all saturated, the analog current signal I _RSSI is 0, and the analog voltage signal V _RSSI is at the minimum value of the range, at this time, the second output value of the conversion control circuit is the minimum value 0, and the digital signal output by the conversion circuit control is a maximum value of 2 ^N -1. When the amplitude of the input signal is within the measurement range of the input signal strength indicator, the digital indication signal output by the conversion control circuit has and only has a unique value corresponding to it.

The error in the strength measurement of the input signal is proportional to the amplitude range of the input signal and inversely proportional to the level of the input signal strength indicator. The number of stages of the input signal strength indicator can be determined according to the number of rectifiers it includes. For example, if it includes 5 rectifiers, then the input signal strength indicator is a 5-level input signal strength indicator. In the case of the same input signal amplitude range, the more stages of the input signal strength indicator, the smaller the error of the strength measurement result of the input signal, so the number of stages of the input signal strength indicator also indirectly determines the number of quantization digits, that is, the above The N.

In this embodiment, the input signal strength indication method can quantize the amplitude of the input signal, and output a binary digital signal corresponding to the input signal strength, without requiring a dedicated analog-to-digital converter to convert the analog signal into a digital signal. Therefore, there is no need to measure the relationship between the input signal amplitude and the output voltage in advance, which not only reduces the cost and structural complexity of the input signal indicator, but also simplifies the entire processing flow of the input signal strength indicator.

In other embodiments, before the step of outputting the digital indication signal corresponding to the amplitude of the input signal, it may also include a conversion control circuit detecting whether the analog voltage signal V _RSSI is at the high threshold voltage Vh and the threshold voltage within M clock cycles Steps within the voltage range determined by the low value V1, if yes, enter the step of outputting a digital indication signal corresponding to the input signal amplitude. Wherein, the M is a positive integer. If it is detected that the analog voltage signal V _RSSI is in the voltage range determined by the highest threshold voltage and the low threshold voltage Vl for M consecutive clocks, it can be considered that the conversion of the input signal strength measurement has been completed, and the digital indication signal can be output. .

Each embodiment in this specification is described in a progressive manner, each embodiment focuses on the difference from other embodiments, and the same and similar parts of each embodiment can be referred to each other.

It should also be noted that in this article, relational terms such as first and second etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that these entities or operations Any such actual relationship or order exists between. Furthermore, the term "comprises", "comprises" or any other variation thereof is intended to cover a non-exclusive inclusion such that a process, method, article, or apparatus comprising a set of elements includes not only those elements, but also includes elements not expressly listed. other elements of or also include elements inherent in such a process, method, article, or device. Without further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article or apparatus comprising said element.

The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention will not 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. an input signal strength indicating device, is characterized in that, comprising:

Analog signal conversion, for being converted to input signal corresponding analog current signal; The range value of described analog current signal and described input signal is negative linear correlation;

Low-pass filter circuit, for described analog current signal is carried out to low-pass filtering treatment, and produces analog voltage signal; The parameter of described low-pass filter circuit is controlled by the first output valve of conversion control circuit;

Voltage comparator circuit, for the threshold voltage of described analog voltage signal and threshold voltage generation circuit generation is compared, and exports comparative result;

Threshold voltage generation circuit, for generation of the high value of threshold voltage and threshold voltage low value; The high value of described threshold voltage and the definite voltage range of described threshold voltage low value are controlled by the second output valve of described conversion control circuit;

Conversion control circuit, for exporting the first output valve or the second output valve according to the voltage ratio of described voltage comparator circuit compared with output control, and the output digital index signal corresponding with input signal amplitude.

2. input signal strength indicating device according to claim 1, is characterized in that, described analog signal conversion comprises N amplitude limiter and N+1 rectifier; Wherein, described amplitude limiter is for input signal is carried out to amplitude amplification, and described rectifier is for ac signal is converted to DC signal, and the DC signal of each rectifier output gathers generation analog current signal; Described N is positive integer.

3. received signal strength indicator device according to claim 1, is characterized in that, described low-pass filter circuit one end is connected with the output of described analog signal conversion, and one end ground connection comprises the electric capacity and the programmable resistance that are arranged in parallel.

4. received signal strength indicator device according to claim 1, it is characterized in that, described voltage comparator circuit comprises the first comparison circuit and the second comparison circuit, described the first comparison circuit is for more described analog voltage signal and the high value of voltage threshold, and described the second comparison circuit is for more described analog voltage signal and voltage threshold low value.

5. received signal strength indicator device according to claim 1, is characterized in that, described threshold voltage generation circuit comprises two divider resistances that programmable current source and series connection arrange; Described programmable current source is controlled by the second output valve of described conversion control circuit.

6. reception signal indicator according to claim 1, is characterized in that, also comprises:

With the clock circuit that described conversion control circuit is connected, be used to described conversion control circuit that clock signal is provided.

7. received signal strength indicator device according to claim 1, is characterized in that, also comprises:

One end is connected with the output of described analog signal conversion, the programmable current mirror that one end is connected with described conversion control circuit, and described programmable current mirror is controlled by the 3rd output valve of described conversion control circuit.

8. an input signal strength indicating means, is applied to, in the input signal strength indicating device as described in claim 1-7 any one, it is characterized in that, comprising:

When described input signal amplitude is zero, conversion control circuit is set to maximum by the second output valve;

Conversion control circuit is carried out self calibration flow process;

Carry out input signal strength measurement procedure;

Export the digital index signal corresponding with input signal amplitude.

9. input signal strength indicating means according to claim 8, it is characterized in that, described self calibration flow process comprises: in the situation that analog voltage signal is greater than the high value of threshold voltage, described conversion control circuit reduces the first output valve, and the resistance value that control reduces low-pass filter circuit is to reduce the numerical value of described analog voltage signal; In the situation that described analog voltage signal is less than threshold voltage low value, described conversion control circuit increases described the first output valve, controls the resistance value of the described low-pass filter circuit of increase to increase the numerical value of described analog voltage signal;

Repeat described self calibration flow process, until the numerical value of described analog voltage signal is positioned at the high value of described threshold voltage and the definite voltage range of threshold voltage low value.

10. input signal strength indicating means according to claim 8, it is characterized in that, described self calibration flow process comprises: in the situation that analog voltage signal is greater than the high value of threshold voltage, described conversion control circuit reduces the 3rd output valve, controls and reduces analog current signal to reduce the numerical value of described analog voltage signal; In the situation that described analog voltage signal is less than threshold voltage low value, described conversion control circuit increases described the 3rd output valve, controls and increases analog current signal to increase the numerical value of described analog voltage signal;

Repeat described self calibration flow process, until the numerical value of described analog voltage signal is positioned at the high value of described threshold voltage and the definite voltage range of threshold voltage low value.

11. input signal strength indicating means according to claim 8, is characterized in that, described input signal strength measurement procedure comprises:

Described conversion control circuit is monitored analog voltage signal by voltage comparator circuit, when described analog voltage signal is less than threshold voltage low value, described conversion control circuit reduces the second output valve, and the electric current that control reduces described programmable current source is to reduce threshold voltage; When described analog voltage signal is greater than the high value of threshold voltage, described conversion control circuit increases described the second output valve, controls the electric current of the described programmable current source of increase to increase threshold voltage; Until the numerical value of described analog voltage signal is positioned at the high value of described threshold voltage and the definite voltage range of threshold voltage low value.

12. input signal strength indicating means according to claim 8, is characterized in that, before the output digital index signal corresponding with input signal amplitude, also comprise:

Conversion control circuit detects analog voltage signal in M clock cycle whether all in the high value of threshold voltage and the definite voltage range of threshold voltage low value, if so, enters the step of exporting the digital index signal corresponding with input signal amplitude; Described M is positive integer.

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