KR101172293B1 - Method and Apparatus for Removing Passive Intermodulation - Google Patents

Abstract

The present invention relates to a passive element intermodulation signal cancellation method and apparatus.

The present invention provides a device for removing an intermodulation signal from an intermodulation signal generated by a passive device, the apparatus comprising: receiving a first signal of a first frequency component and a second signal of a second frequency component; An estimated intermodulation signal generator for generating an estimated intermodulation signal of the component and controlling and outputting a nonlinear characteristic of the generated estimated intermodulation signal; And a correlation filtering unit configured to receive the signal A including the intermodulated signal and the outputted estimated intermodulated signal, extract a correlation between the signal A and the estimated intermodulated signal, and remove the intermodulated signal included in the signal A. Provided is a passive element intermodulation signal removal device.

According to the present invention, by effectively eliminating the influence due to the intermodulation signal generated in the passive device provided in the communication equipment, there is an effect of improving the quality of service.

Passive Device, Intermodulation, Communication Equipment

Description

Passive device intermodulation signal removal method and apparatus {Method and Apparatus for Removing Passive Intermodulation}

The present invention relates to a passive element intermodulation signal cancellation method and apparatus. More particularly, the present invention relates to a passive element intermodulation signal removal method and apparatus having an effect of effectively eliminating an effect due to an intermodulation signal generated in a passive element provided in communication equipment and improving service quality.

Mobile communication services continue to diversify, and the number of subscribers is also increasing. In accordance with this trend, mobile operators are providing services by securing multiband frequencies. That is, various frequencies are used in the same mobile communication method to provide a service, or a communication network is configured so that a plurality of mobile communication methods overlap, and various frequencies are used to provide a service according to each mobile communication method. .

The provision of services using these various frequencies provides mobile operators with the opportunity to open new markets, but the cost of network construction is a burden. Therefore, it is necessary to reduce the utilization by utilizing the existing communication network to the maximum, and research on this is being conducted.

However, due to nonlinear characteristics in communication equipment such as base stations and repeaters included in the communication network, there are serious problems in using various frequencies. In the process of processing signals of different frequency components, an intermodulation (also called 'modulation') signal having a nonlinear characteristic that distorts a desired signal is generated. In particular, an antenna, a power supply line, Due to intermodulation signals generated from passive devices such as splitters, noise is generated in adjacent frequency bands, thereby lowering the signal-to-noise ratio, thereby degrading service quality.

An object of the present invention for solving this problem is to improve the quality of service by eliminating the effect of the intermodulation signal generated in the passive device provided in the communication equipment.

Another object of the present invention for solving this problem is to be able to adjust the (estimated) intermodulation signal generated arbitrarily in order to remove the intermodulation signal generated in the passive element through the control of input and output characteristics and non-linear characteristics, By generating an estimated intermodulation signal having a high correlation with the intermodulation signal to be removed, it is possible to improve the cancellation performance of the intermodulation signal.

According to an aspect of the present invention for achieving the above object, in the intermodulation signal removal device for removing the intermodulation signal generated in the passive element, the first signal and the second frequency of the first frequency component An estimated intermodulation signal generator configured to receive a second signal of a component, generate an estimated intermodulation signal of a third frequency component, and control and output a nonlinear characteristic of the generated estimated intermodulation signal; And receiving a signal A including an intermodulated signal and the output estimated intermodulated signal, extracting a correlation between the signal A and the estimated intermodulated signal, and removing the intermodulated signal included in the signal A. It provides a passive element intermodulation signal removal device comprising a correlation filtering unit.

According to another aspect of the present invention for achieving this object, a method for removing an intermodulation signal generated in a passive element, (a) the first signal and the second frequency component of the first frequency component Receiving an input signal receiving a second signal; (b) Estimated intermodulation by nonlinear characteristic control, which generates an estimated intermodulated signal of a third frequency component from the inputted first and second signals, and controls and outputs a nonlinear characteristic of the generated estimated intermodulated signal. Signal generation step; And (c) receiving a signal A including an intermodulated signal and an estimated intermodulated signal output by controlling the nonlinear characteristics, extracting a correlation between the signal A and the estimated intermodulated signal, and including the signal A in the signal A. It provides a passive element intermodulation signal removing method comprising the step of removing the intermodulation signal to remove the intermodulated signal.

As described above, according to the present invention, the effect of the intermodulation signal generated in the passive device provided in the communication equipment is eliminated, thereby improving the service quality.

In addition, according to the present invention, it is possible to adjust the (estimated) intermodulation signal, which is arbitrarily generated in order to remove the intermodulation signal generated from the passive element, by controlling the input / output characteristics and the nonlinear characteristics, By being able to generate an estimated intermodulation signal having a high correlation, there is an effect of improving the cancellation performance of the intermodulation signal.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to designate the same or similar components throughout the drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention unclear.

1 is a schematic diagram of an apparatus for removing a passive element intermodulation signal according to the present invention.

As illustrated in FIG. 1, a passive intermodulation canceling device (PIMC) for canceling an intermodulation signal generated in a passive device includes a first frequency component. Receiving the first signal 10 and the second signal 20 of the second frequency component, generating the estimated intermodulation signal 30 of the third frequency component, and controlling the nonlinear characteristics of the generated estimated intermodulation signal. Input the estimated intermodulated signal generator 100 and the estimated intermodulated signal 30 output from the estimated intermodulated signal generator 100 and the signal A 40 including the intermodulated signals generated from the passive element. And a correlation filtering unit 200 which extracts a correlation between the signal A 40 and the estimated intermodulation signal 30 and removes the intermodulation signal included in the signal A 40. In addition, the passive element intermodulation signal removing device includes an A / D converter for converting an analog signal into a digital signal, a D / A converter for converting a digital signal into an analog signal, and a coupling unit for detecting signal characteristics. It may be included as.

The term "Passive Inter Modulation (PIM) signal generated in passive devices" referred to in the present invention is generated from passive devices such as antennas, feeders, and dividers in communication equipment by allowing the communication equipment to use a plurality of frequencies. In this case, noise is generated at frequencies in adjacent bands, thereby lowering signal-to-noise ratios in reception frequency bands, thereby degrading service quality. Hereinafter, "intermodulation signal generated in the passive element" will be described as "intermodulation signal". In addition, in order to eliminate such intermodulation signals, signals generated so as to be highly correlated with the intermodulation signals are defined as "estimated intermodulation signals" and may be generated in active devices and / or passive devices. This " estimated intermodulation signal " of the third frequency component is a signal of frequency component combined with the sum and difference of harmonic frequencies between the first signal of the first frequency component and the second signal of the second frequency component. . For example, if the first frequency is f1 and the second frequency is f2, the estimated intermodulation signal is a signal of a third frequency component including (2f1-f2), (2f2-f1), and the like.

The cancellation performance of the intermodulation signal in the passive device intermodulation signal removal apparatus greatly varies depending on how the estimated intermodulation signal generator 100 generates the estimated intermodulation signal. Accordingly, the present invention controls the nonlinear characteristics, the input characteristics, and the output characteristics of the estimated intermodulation signal generator 100 included in the passive element intermodulation signal removal device, thereby making the estimated mutual correlation with the intermodulation signal even higher. It is possible to generate a modulated signal. This will be described in more detail with reference to FIG. 2.

2 is a diagram of an estimated intermodulation signal generator 100 generating an estimated intermodulation signal by performing control on input characteristics, nonlinear characteristics, and output characteristics.

Referring to FIG. 2, the estimated intermodulation signal generator 100 generating an estimated intermodulation signal by performing control on input characteristics, nonlinear characteristics, and output characteristics may include an input signal controller 110 for controlling input characteristics. A nonlinear controller 120 for controlling the nonlinear characteristics, an output signal controller 140 for controlling the output signal, and a filtering unit 130.

The input signal controller 110 controls input characteristics by adjusting signal strength or signal waveforms of the first signal 10 of the first frequency component and the second signal 20 of the second frequency component, which are input signals, and inputting the input signal. The first signal 11 whose characteristic is controlled and the second signal 21 whose input characteristic are controlled are output. The input signal controller 110 adjusts the signal strength or signal waveform of the first signal 10 and the second signal 20 based on the input control signal transmitted from the input signal controller 111.

The nonlinear control unit 120 for controlling the nonlinear characteristics may be configured as a nonlinear semiconductor device, and thus, the nonlinearity of the nonlinear control unit 120 may vary according to the power supplied, thereby being generated from the nonlinear control unit 120. The nonlinearity of the estimated intermodulated signal (generated) output may vary. This means that the estimated intermodulation signal can be adjusted to have characteristics similar to those of the intermodulation signal generated from the passive element.

The nonlinear control unit 120 controls the nonlinear characteristics of the generated estimated intermodulation signal according to the power supplied from the power generation unit 122 and outputs the estimated intermodulation signal whose nonlinear characteristics are controlled. At output, the signals 11 and 21 of the first and second frequency components may be included, as well as the estimated intermodulation signal of the third frequency component whose nonlinear characteristics are controlled. The power generator 122 mentioned above generates (generates) the corresponding power according to the power control signal transmitted from the power controller 121 and supplies it to the nonlinear controller 120.

The signal 31 output from the nonlinear control unit 120 may include not only the estimated intermodulation signal of the third frequency component whose nonlinear characteristic is controlled, but also the signals 11 and 21 of the first frequency component and the second frequency component. . Therefore, the estimated intermodulation signal generator 100 may include an estimated intermodulation signal whose nonlinear characteristics of the third frequency component are controlled, and a signal including the signals 11 and 21 of the first frequency component and the second frequency component. The filter 130 may include a filtering unit 130 for filtering only the estimated intermodulation signal whose nonlinear characteristic of the third frequency component is controlled and outputting the filtered signal 32.

The output signal controller 140 controls the signal strength or signal waveform of the estimated intermodulation signal 32 in which only the signal of the third frequency component is filtered out of the signal 31 outputted by controlling the nonlinear characteristic by the nonlinear controller 120. do. This control is based on the output control signal transmitted from the output signal adjusting unit 141. The signal 30 outputted with the output characteristic controlled by the output signal controller 140 is an estimated intermodulation signal used to remove the intermodulation signal.

According to the above-described passive element intermodulation signal removing apparatus according to the present invention, the (estimated) intermodulation signal generated arbitrarily in order to remove the intermodulation signal generated from the passive element can be adjusted by controlling input / output characteristics and nonlinear characteristics. By generating an estimated intermodulation signal having a high correlation with the intermodulation signal to be removed, there is an effect of improving the cancellation performance of the intermodulation signal. By removing the impact more effectively, it is possible to provide improved quality of service.

3 is a flowchart of a passive element intermodulation signal removal method according to the present invention.

As shown in FIG. 3, the method for removing an intermodulation signal generated in a passive device includes receiving an input signal (S300) for receiving a first signal of a first frequency component and a second signal of a second frequency component. Generating an estimated intermodulation signal of a third frequency component from the first signal and the second signal, and generating an estimated intermodulation signal by controlling the nonlinear characteristics of the generated estimated intermodulation signal (S304) And a signal A including an intermodulation signal generated from a passive element and an estimated intermodulation signal output by controlling a nonlinear characteristic, and extracting a correlation between the signal A and the estimated intermodulation signal, and included in the signal A. And removing the intermodulation signal (S310).

The generation of the estimated intermodulation signal by nonlinear characteristic control (S304) receives power generated according to the power control signal, and controls the nonlinear characteristic of the generated estimated intermodulation signal according to the supplied power.

In the passive element intermodulation signal removal method according to the present invention, as in step S304, the nonlinear characteristic is controlled to generate an estimated intermodulation signal. In addition, an estimated complementary modulation signal may be generated by controlling input characteristics of the first signal of the first frequency component and the second signal of the second frequency component, which are input signals, and controlling the output characteristics of the generated estimated intermodulation signal. The final estimated intermodulation signal may be output.

Controlling and generating input characteristics and output characteristics as well as generating estimated intermodulation signals by nonlinear characteristic control will be described in more detail with reference to FIG. 4.

After the input signal receiving step S300, an input signal control step S302 of controlling signal strength or signal waveforms of the first and second signals, which are input signals, may be performed based on the input input control signal. .

After generating the estimated intermodulation signal by the nonlinear characteristic control step S304, a filtering step S306 of filtering and passing only the estimated intermodulation signal whose nonlinear characteristic is controlled may be performed.

After the estimated intermodulation signal generation step (S304) by the nonlinear characteristic control, an output signal control step of controlling the signal strength or signal waveform for the estimated intermodulated signal to which the nonlinear characteristic is controlled and output based on the input output control signal. It may include (S308). This output signal control step (S308) may be performed after the filtering step (S306), as shown in FIG.

According to the aforementioned passive element intermodulation signal removal method according to the present invention, the (estimated) intermodulation signal arbitrarily generated in order to remove the intermodulation signal generated from the passive element can be adjusted through control of input / output characteristics and nonlinear characteristics. By generating an estimated intermodulation signal having a high correlation with the intermodulation signal to be removed, there is an effect of improving the cancellation performance of the intermodulation signal. By removing the impact more effectively, it is possible to provide improved quality of service.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

As described above, the present invention is applied to the technology and apparatus for removing the intermodulation signal generated by the passive element, to effectively remove the effect of the intermodulation signal generated by the passive element provided in the communication equipment, It is a very useful invention with the effect of improving the quality.

1 is a schematic diagram of an apparatus for removing a passive element intermodulation signal according to the present invention;

2 is a diagram of an estimated intermodulation signal generator for generating an estimated intermodulation signal by performing control on input characteristics, nonlinear characteristics, and output characteristics;

3 is a flow chart for a passive element intermodulation signal removal method according to the present invention;

4 is a detailed flowchart of a passive element intermodulation signal removal method according to the present invention.

Description of the Related Art

100: estimated intermodulation signal generator

110: input signal controller

111: input signal controller

120: nonlinear control unit

121: input power control unit

122: input power generator

130: filtering unit

140: output signal control unit

141: output signal control unit

Claims (13)

In the intermodulation signal removal device for removing the intermodulation signal generated in the passive element, An estimation for receiving the first signal of the first frequency component and the second signal of the second frequency component, generating an estimated intermodulation signal of the third frequency component, and controlling and outputting the nonlinear characteristics of the generated estimated intermodulation signal; An intermodulation signal generator; And Correlation that receives a signal A including an intermodulated signal and the output estimated intermodulated signal, extracts a correlation between the signal A and the estimated intermodulated signal, and removes the intermodulated signal included in the signal A. Filtering section Passive device intermodulation signal removal device comprising a. The method of claim 1, The estimated intermodulation signal generator, And a nonlinear control unit for controlling the nonlinear characteristics of the generated estimated intermodulation signal, wherein the nonlinear control unit controls the nonlinear characteristics of the generated estimated intermodulation signal according to power supplied from a power generation unit. Passive element intermodulation signal cancellation device. 3. The method of claim 2, The power generation unit, And generating the power according to a power control signal transmitted from a power control unit and supplying the power to the nonlinear control unit. The method of claim 1, The estimated intermodulation signal generator, And an input signal controller configured to control signal strength or signal waveforms of the first and second signals. 5. The method of claim 4, The input signal controller, Passive device intermodulation signal removing device, characterized in that for adjusting the signal strength or the signal waveform based on the input control signal transmitted from the input signal adjusting unit. The method of claim 1, The estimated intermodulation signal generator, And an output signal controller configured to control signal strength or signal waveform of the estimated intermodulated signal output by controlling the nonlinear characteristic. The method according to claim 6, The output signal control unit, And controlling the signal strength or the signal waveform based on an output control signal transmitted from an output signal adjusting unit. The method of claim 1, The estimated intermodulation signal generator, And a filtering unit for filtering and passing only the estimated intermodulation signal whose nonlinear characteristic is controlled. In the method for removing the intermodulation signal generated in the passive device, (a) receiving an input signal receiving a first signal of a first frequency component and a second signal of a second frequency component; (b) Estimated intermodulation by nonlinear characteristic control, which generates an estimated intermodulated signal of a third frequency component from the inputted first and second signals, and controls and outputs a nonlinear characteristic of the generated estimated intermodulated signal. Signal generation step; And (c) receiving a signal A including an intermodulated signal and an estimated intermodulated signal controlled and output from the nonlinear characteristic, extracting a correlation between the signal A and the estimated intermodulated signal, and included in the signal A; An intermodulation signal removing step of removing the intermodulation signal Passive device intermodulation signal removal method comprising a. 10. The method of claim 9, Step (b) is, And receiving a power generated according to a power control signal, and controlling a nonlinear characteristic of the generated estimated intermodulation signal according to the supplied power. 10. The method of claim 9, After said step (a), And an input signal control step of controlling a signal strength or a signal waveform for the first signal and the second signal based on the input control signal. 10. The method of claim 9, After step (b), And filtering through only the estimated intermodulated signal whose nonlinear characteristic is controlled. 10. The method of claim 9, After step (b), And an output signal control step of controlling a signal strength or a signal waveform for the estimated intermodulated signal outputted by controlling the nonlinear characteristic based on the inputted output control signal.

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