KR100722244B1 - Reverse noise detection system and method - Google Patents

Abstract

 The present invention relates to a backward noise search system and method.

In accordance with an aspect of the present invention, a reverse noise search system includes: a frequency spectrum measuring unit measuring a signal spectrum within a measurement period of a user frequency band of a reverse frequency band; A frequency spectrum analyzer for analyzing the spectrum measured by the frequency spectrum analyzer; An alarm unit for alarming when a result of the frequency spectrum analyzer exceeds a predetermined value; And a control unit for controlling the output of the signal transmission equipment of the repeater or the base station according to the alarm.

The present invention can improve the call quality by measuring the noise of the frequency band used, to minimize the transmission power burden of the repeater or base station, it is possible to alarm for the occurrence of noise.

Reverse channel, noise search, maximum measurement, user frequency band, unused frequency band

Description

Reverse Noise Detection System And Method

1 is a flowchart illustrating a conventional reverse noise search method.

2 is a block diagram illustrating a reverse noise search system according to an exemplary embodiment of the present invention.

3 is a diagram illustrating a frequency band and an interval of a frequency spectrum measuring unit of FIG. 2;

4 is a diagram illustrating a maximum measurement value and an address collected from a signal in which noise is coupled by the frequency spectrum analyzer of FIG. 2; FIG.

5 is a screen configuration diagram illustrating a plurality of signal spectrums measured in a unit measurement section of a signal in which noise is coupled by the frequency spectrum measuring unit of FIG. 2.

FIG. 6 is a diagram illustrating an analysis table analyzing the signal spectrum of FIG. 5. FIG.

FIG. 7 is a diagram illustrating a maximum measurement value and an address collected from a signal in which normal traffic signals are combined by the frequency spectrum analyzer of FIG. 2; FIG.

8 is a screen configuration diagram illustrating a plurality of signal spectrums measured in a unit measurement section of a signal in which a normal traffic signal is combined by the frequency spectrum measuring unit of FIG. 2.

9 is a diagram illustrating an analysis table of the signal spectrum of FIG. 7.

10 is a graph showing characteristics of signals generated by normal traffic channels.

11 is a diagram showing a difference between an average noise level of an unused frequency band and a maximum measured value of a used frequency band in a reverse channel.

12 is a flowchart illustrating a reverse noise search method according to an embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

100: mobile station 200: noise

300: reverse noise search system of repeater or base station

310: frequency spectrum measurement unit 320: frequency spectrum analysis unit

330: alarm unit 340: control unit

 The present invention relates to a reverse noise search system and method, in particular, by analyzing the spectral waveform of the reverse noise to change the system setting value according to the importance of the effect on the system when the reverse noise occurs, the impact on the call quality and the base station of the surrounding telephone environment The present invention relates to a reverse noise search system and a method for minimizing the noise.

With the recent development of communication-related technologies, many communication services using wired / wireless are provided to users. The development and dissemination of optical fiber and the development of related systems have made it possible to realize the optical communication network, and the transmission speed and quantity of voice and data have been greatly increased. In addition, wireless communication systems have evolved from services that only support voice services, and have now reached a level where voice and data related services can be provided even during high-speed movement. In particular, mobile communication has been spotlighted as a medium capable of transmitting and receiving information by controlling time and space to anyone, anytime, anywhere, by using a free space, which is a wireless transmission medium, on the premise of subscriber mobility.

Such a system for mobile communication can be simply represented by a mobile station and a base station, and a call channel and a data call are formed by generating and controlling a call channel formed between a plurality of mobile stations at the base station. When a signal is transmitted from a base station to a mobile station or when a mobile station attempts to access a base station, it is often difficult to establish a call channel due to the geographical influence or the external environment. Further repeaters that can relay the transmission and reception of signals.

Meanwhile, the repeater and the base station monitor the noise generation of the channel for the reverse channel transmitting the signal from the mobile station to the base station, and when the noise is detected, attenuates or shuts down the output of the signal transmitting / receiving equipment, Minimize the damage caused by the base station.

1 is a flowchart illustrating a conventional reverse channel noise detection method.

Referring to FIG. 1, the conventional noise detection method for the reverse channel designates an unused band in which the mobile station does not attempt to connect to the reverse channel (S1).

Next, the spectral waveform is divided into predetermined bands for a predetermined period and measured based on the center point of the designated unused band (S2).

Next, the difference between the maximum value and the minimum value of each predetermined band is represented as a Peak to Peak value (S3).

Next, it is checked whether the deviation of the Peak to Peak value is increased (S4).

Finally, when the deviation of the Peak to Peak value increases, the signal currently detected is determined as noise, and accordingly the output of the equipment is changed (S5).

On the other hand, even when normal traffic changes occur due to an increase in traffic in a reverse use band or an increase in noise level in a reverse band due to a change in an external propagation environment, that is, multi-path fading. The variation of the peak level increases. In such a situation, when the conventional reverse channel noise detection method is applied, the output of equipment due to the noise detection is changed, and as a result, an error occurs that degrades the call quality of the mobile station. In addition, the conventional reverse channel noise detection method does not consider the generation of noise in the use band, there is a disadvantage that it is impossible to measure when the noise of the use band.

Accordingly, an object of the present invention to improve the call quality by measuring the noise of the frequency band used, to minimize the transmission power burden of the repeater or base station, to provide a reverse noise search system and method capable of alarm for noise generation have.

It is another object of the present invention to more accurately distinguish whether a signal generated in a reverse channel is a signal for normal traffic or a signal generated by noise, classify the detected noise according to a level class, and classify each noise level. According to the present invention to provide a reverse noise search system and method that can minimize the output burden of the base station by adaptively adjusting the output of the repeater or base station.

Another object of the present invention is to detect the signals at regular intervals in the user frequency band used by the mobile station in the reverse channel, calculate the standard deviation of the detected signals, and determine the noise when a value higher than the specified value is detected. In other cases, the present invention provides a reverse noise search system and method capable of determining a signal by normal traffic or multipath fading.

Lastly, another object of the present invention is to measure signals in a user frequency band in a reverse channel, at regular intervals for a predetermined time, give an address value to measured signals, and measure a maximum measured value and Collecting data by storing the address having the maximum measurement value, and comparing the standard deviation of the maximum measurement value and the repetition degree of the address where the maximum measurement value is detected, whether the signal detected by the noise and normal traffic It is to provide a reverse noise search system and method that can be determined more closely.

In order to achieve the above object, a reverse noise search system according to the present invention includes a frequency spectrum measuring unit for measuring a signal spectrum within a measurement period of a user frequency band of a reverse frequency band; A frequency spectrum analyzer for analyzing the spectrum measured by the frequency spectrum analyzer; An alarm unit for alarming when a result of the frequency spectrum analyzer exceeds a predetermined value; And a control unit for controlling the output of the signal transmission equipment of the repeater or the base station according to the alarm.

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The controller may activate the frequency spectrum measuring unit when the maximum measured value of the used frequency band is 5 dB or more different from the average of the absolute noise level of the reverse unused frequency band.

The measurement section is characterized in that less than the frequency band used.

The use frequency band is 1.23MHz, the measurement section is characterized in that 1MHz.

The frequency spectrum analyzer divides the measurement section into a unit measurement section, assigns sequential addresses to each unit measurement section, a signal having a maximum measurement value among signal measurement values of each unit measurement section, and the maximum It is characterized by storing an address having a measured value.

The frequency spectrum analyzer may perform the measurement at least once at regular time intervals and determine the signal as noise by using the standard deviation of the maximum measurement values and the number of detections of the same address among the addresses. It is done.

The frequency spectrum analyzer determines that the signal is noise when the standard deviation of the maximum measurement values is 5 dB or more and the same address detection frequency is 80 percent or more of the total detection times, and the set ratio and standard deviation setting value are adjusted. It is characterized by possible.

The frequency spectrum analyzer, the unit measurement section is characterized in that 30KHz.

The alarm unit may classify the intensity of the noise for each grade and determine an alarm level according to the classified grade.

A reverse noise search method according to an embodiment of the present invention includes a first step of measuring a signal spectrum within a measurement interval of a user frequency band of a reverse frequency band; A second step of calculating an average of an absolute noise level in an unused frequency band of the reverse frequency bands; A third step of comparing the maximum measured value of the user frequency band with an average of the absolute noise level in the unused frequency band; A fourth step of analyzing the signal spectrum in the measurement section according to the result of the third step and comparing it with a predetermined value; A fifth step of alarming when the analysis result of the fourth step exceeds a predetermined value; And a sixth step of adjusting the output of the signal transmitting equipment of the repeater or the base station according to the alarm.

The reverse noise search method may further include a sixth step of adjusting the output of the signal transmitting equipment of the repeater or the base station according to the alarm.

The first step is characterized in that the measuring section is less than the frequency band used.

In the third step, if the difference between the maximum measured value of the user frequency band and the average of the absolute noise level in the unused frequency band is more than 5dB, the fourth step is performed.

The fourth step may include: dividing the measurement section into unit measurement sections, assigning sequential addresses to each unit measurement section, and having a maximum measurement value among signal measurement values of each unit measurement section; A first substep of collecting an address having a measurement value; And a second substep of performing the first substep at least one or more times, and performing noise determination using the standard deviation of the maximum measured values obtained therefrom and the number of detections of the same address among the addresses. do.

In the second sub-step, the predetermined value is a standard deviation of the maximum measured values is 5dB or more, the same address detection frequency is set to 80% or more of the total detection frequency, the signal when the predetermined value is exceeded Is determined as noise.

The fifth step is characterized by classifying the intensity of the noise by class, and determining the alarm level according to the classified class.

Other objects and advantages of the present invention in addition to the above objects will become apparent from the detailed description of the embodiments with reference to the accompanying drawings.

Hereinafter, with reference to Figures 2 to 12 attached to a preferred embodiment of the present invention will be described in detail.

2 is a diagram schematically illustrating a reverse noise search system according to an exemplary embodiment of the present invention.

Prior to the description, the reverse frequency band is 10MHz, the frequency band used is 1.23MHz, and the spectrum measurement interval is 500KHz in the left and right frequency bands within the used frequency band, and the measurement time is approximately 10 seconds. The unit measurement section of the spectrum measurement section shall be measured every 30KHz. Each of these numerical values is arbitrary for the experiment, and each frequency band, measurement section, measurement time, unit measurement section, etc. may be changed as necessary.

2, the reverse noise search system 300 of the present invention is a frequency spectrum measurement unit 310 for measuring the spectrum of the signal transmitted from the mobile station 100 or the noise 200 in the frequency band of the reverse frequency band The alarm unit for alarming the control unit 340 when the results of the frequency spectrum analyzer 320 and the frequency spectrum analyzer 320 that analyze the spectrum measured by the frequency spectrum measurer 310 exceed a predetermined value ( 330 and a control unit 340 for adjusting the output of the signal transmission equipment according to the reception of the alarm signal from the alarm unit 330. Here, the predetermined value may be an average of the absolute noise level in the unused frequency band of the reverse frequency band.

As shown in FIG. 3, the frequency spectrum measuring unit 310 measures a spectrum of 1 MHz at each measurement interval of 1 MHz at 500 KHz, based on the center point of the frequency band, among every 30 KHz.

As shown in FIG. 4, the frequency spectrum analyzer 320 assigns an address to each measured value measured every 30 KHz for a given measurement time, and assigns an address, for example, measured values 1 to 33. Store the maximum measured value address separately. Referring to the drawings, when the measured value at address 8 of the addresses 1 to 33 is shown as the maximum measured value -50 dBm during the first measured time data1, the maximum measured value address of the first measured time data1 Save eight. If the measured value of address 8 is the maximum measured value -47 dBm, similarly to the first measured time data1 among the addresses 1 to 33 during the second measured time data1, the second measured time data2 Save the maximum measured value address 8. In the same manner, the maximum measured value addresses of the third to tenth measurement time data3 to data10 are stored. As the number of occurrences of the same address (address 8) is 8 times among 10 measurements, and the standard deviation of the maximum measured values is 2.76 dB, the signal currently measured is determined as noise 200. The number of measurements can be applied more times to make the test more precise, and the number of address occurrences can be applied if it is calculated by a percentage rate or more. When the standard deviation of the measured maximum measured values is within 5 dB, it may be determined as the noise 200.

FIG. 5 is a diagram illustrating a spectrum of a waveform in which noise 200 is generated in a reverse channel, and FIG. 6 is a table analyzing the spectrum of FIG. 5.

5 and 6, the noise 200 is generated at the center frequency of the reverse frequency band, the elapsed time when the generated noise 200 is measured, and the maximum measured value is 10 times at the specific address (address 31). The standard deviation of the maximum measured values is 1.4 dB and is less than 5 dB, which is a standard deviation standard of noise 200, and is determined as noise 200.

On the other hand, referring to Figure 7, the frequency spectrum analyzer 320 appears two times when the same address occurs among the maximum measurement values measured 10 times (data1 ~ data10), the standard deviation of the maximum measurement values is 5.5dB As it appears, it is determined to be a signal according to normal traffic.

This will be described with reference to FIGS. 8 and 9. FIG. 8 is a diagram illustrating a spectrum of a waveform in which a signal is generated according to a user's connection attempt to a reverse channel. FIG. 9 is a table analyzing the spectrum of FIG. 8.

Referring to FIGS. 8 and 9, as a result of waveform measurement analysis according to traffic conversion of the reverse frequency band, the address of the maximum measured value does not occur repeatedly as the waveform caused by traffic continuously changes, and the standard deviation is 6.8 dB. The low level deviation is higher than the noise level standard deviation of 5 dB, which is considered a normal traffic signal.

The noise 200 has a small standard deviation, and normal traffic exhibits a large standard deviation. Referring to FIG. 10, the mobile station 100 transmits a message for forming a call call and forming a data call, and the confirmation process for the message is repeated several times until the connection is successful as shown in the figure. do. If the first attempt to connect at a predetermined power, and if there is no response from the base station, after a predetermined time the power is increased by a predetermined amount and attempts to connect again. If this attempt is made until it reaches a specified maximum power and there is no response, it starts a new attempt again. When the mobile station 100 does not attempt to connect to the base station with a sufficiently strong signal from the beginning, the capacity of the mobile station 100 is greatly changed due to interference in the reverse link. Until then, a method of increasing the transmission power of the mobile station 100 step by step is used. Due to the characteristics of the mobile station 100, the traffic distribution in the reverse channel used while the mobile station 100 attempts to establish a communication channel with the base station has a form in which the maximum measurement value of the signal is gradually changed. . Therefore, when the mobile station 100 obtains the standard deviation of the signal generated, the standard deviation is large. However, the noise 200 signal does not show a large standard deviation. That is, since the noise 200 signal does not increase or decrease the size of the signal step by step unlike the mobile station 100, the noise 200 signal has a constant size for a predetermined time regardless of whether the noise 200 signal itself is large or small. A special noise 200 signal, for example, even noise in the form of a pulse, when the magnitudes of the pulse values are collected and examined, the standard deviation value is small.

When the frequency spectrum analyzer 320 determines the analysis result of the signal as the noise 200, the alarm unit 330 classifies the intensity of the noise 200 by grade and determines the degree of alarm according to the classified grade. To alarm the controller 340. Specifically, the alarm unit 330 determines whether the noise of the maximum measured value 200 when the maximum measured value of the used frequency band differs by 5 dB or more from the average of the absolute noise 200 levels of the reverse unused frequency band. The frequency spectrum analyzer 320 may be inspected and graded according to the difference between the average noise level of the unused frequency band and the maximum measured value of the used frequency band when the noise 200 is determined. As an example of the rating, 5dB is normal, 10dB is minor, 15dB is major, and 20dB is classified as each and transmits each noise 200 level to the controller 340.

The controller 340 adjusts the output according to the noise 200 level transmitted by the alarm unit 330. For example, when the control unit 340 receives the “normal” alarm from the alarm unit 330, when the transmission / reception output of the repeater or the base station equipment is “100”, the control unit 340 increases the output or changes it less depending on the situation. do. When the controller 340 receives the "Minor" from the alarm unit 330, the controller 340 increases the output change width larger than that of the "normal". The reverse noise search system of the present invention can more appropriately respond to the occurrence of the noise 200 by adjusting the output change width according to each noise 200 level in the above manner. Meanwhile, as illustrated in FIG. 11, the controller 340 controls to operate the reverse noise search system when the maximum measured value of the user frequency band is 5 dB or more than the average level of the absolute noise 200 level of the unused frequency band of the reverse channel. Can be.

12 is a diagram illustrating a reverse noise search method according to an embodiment of the present invention.

Referring to FIG. 12, in the reverse noise search method of the present invention, first, a measurement section of a reverse user frequency band is designated, and a frequency spectrum of the designated measurement section is measured (S101).

The frequency band of the reverse channel is measured at 10 MHz, the user frequency band is 1.23 MHz, and the measurement interval for measurement is 1 MHz, the measurement time is measured for 10 seconds, and the unit measurement interval is measured every 30 KHz. The measurement section 1MHz is preferably defined as the left and right 500KHz range based on the center frequency, the measurement time and the unit measurement section may be changed as necessary.

Next, the average noise level value of the unused band is measured. (S102)

Next, the difference between the average noise level measured value of the unused band and the maximum measured value of the used band is compared by 5 dB or more, and when the value is 5 dB or more, the measured value and the address of the user band are collected.

Next, it is checked whether the repetition rate of the collected address and the standard deviation of the maximum measured values have a value equal to or greater than a specified value (S105).

In step S105, if the address repetition rate is less than a certain ratio, or if the standard deviation value of the maximum measurement values is more than the specified value, the measurement signal is determined to be a signal by normal traffic (S110).

In step S105, when the address repetition rate is more than a certain rate, for example, 80% or more, and the standard deviation value of the maximum measured values is a specified value, for example, 5 dB or less, the measurement signal is determined as the noise 200 signal. (S106)

Next, the noise level is determined by comparing the difference between the average noise level of the unused frequency band and the maximum measured value of the frequency band used (S107).

Next, the alarm unit 330 alarms the determined noise level to the controller 340. (S108)

The alarm unit 330 sequentially classifies the noise level into "nomal", "Minor", "Major", and "Critical" according to the size of the noise 200, and "nomal" has a noise level of 5 dB. (200) Minor occurrence, "Minor" noise level is set to 10dB, "Major" noise level is set to 15dB, "Critical" noise level is set to 20dB, respectively, noise level can be classified according to each setting .

Finally, the control unit 340 adjusts the output change width of the repeater or the base station according to the noise level received from the alarm unit 330 (S109).

The reverse noise search system and method of the present invention having the above-described method can more accurately determine whether a signal generated in the reverse channel is a signal for normal traffic or a signal caused by noise 200, and is detected. By dividing the noise 200 class of the signal and adjusting the variation range of the output of the repeater and the base station according to each noise level, the call quality can be improved by more appropriately responding to the noise 200, and the output of the repeater and the base station The burden can be minimized.

As described above, the reverse noise search system and method according to an embodiment of the present invention, it is possible to alarm for the occurrence of noise to improve the call quality by measuring the noise of the frequency band used.

The reverse noise search system and method according to another embodiment of the present invention can more accurately distinguish whether a signal generated in a reverse channel is a signal for normal traffic or a signal generated by noise, and classifies the detected noise as a level grade. According to the classification, and by adaptively adjusting the output of the repeater or the base station according to the divided noise level, it is possible to minimize the output burden of the base station.

In a reverse noise search system and method according to another embodiment of the present invention, a signal is detected at a predetermined interval in a user frequency band used by a mobile station in a reverse channel, and the standard deviation of each detected signal is calculated to be equal to or greater than a specified value. If a value is detected, it can be determined as noise, otherwise it can be determined as a signal by normal traffic or multipath fading.

Finally, the reverse noise search system and method according to another embodiment of the present invention, by measuring the user frequency band in the reverse channel in a measurement interval, at a predetermined interval for a predetermined time, and gives an address value to the measured signals And collect the data by storing the maximum measured value and the address having the maximum measured value at one measurement time, and comparing the standard deviation of the maximum measured values with the repetition degree of the address at which the maximum measured value is detected. It is possible to determine more closely whether the signal is caused by noise and normal traffic.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical scope of the present invention should not be limited by the detailed description of the invention described in the specification, but should be determined by the claims.

Claims (17)

A frequency spectrum measuring unit measuring a signal spectrum within a measurement period of a user frequency band of the reverse frequency band; A frequency spectrum analyzer for analyzing the spectrum measured by the frequency spectrum analyzer; An alarm unit for alarming when a result of the frequency spectrum analyzer exceeds a predetermined value; And And a control unit for adjusting the output of the signal transmitting equipment of the repeater or the base station according to the alarm. delete The method of claim 1, wherein the control unit, And activating the frequency spectrum measuring unit when a maximum measured value of the used frequency band differs by 5 dB or more from an average of the absolute noise level of the reverse unused frequency band. The method of claim 1, wherein the measurement section, The reverse noise search system, characterized in that less than the frequency band used. The method of claim 1, wherein the frequency band used, 1.23MHz, the measurement section is a reverse noise search system, characterized in that 1MHz. The method of claim 1, wherein the frequency spectrum analyzer, The measurement section is divided into unit measurement sections, and sequential addresses are assigned to each unit measurement section, and a signal having a maximum measurement value and an address having the maximum measurement value among the signal measurement values of each unit measurement section. And a reverse noise search system. The method of claim 6, wherein the frequency spectrum analyzer, And performing the measurement at least once at regular time intervals and determining the signal as noise by using the standard deviation of the maximum measurement values and the number of detections of the same address among the addresses. The method of claim 7, wherein the frequency spectrum analyzer, And if the standard deviation of the maximum measurement values is 5 dB or more and the same address detection frequency is 80 percent or more of the total detection frequency, the signal is determined as noise. The method of claim 6, wherein the frequency spectrum analyzer, And the unit measurement section is 30KHz. The method of claim 1, wherein the alarm unit, And classifying the intensity of the noise by class and determining an alarm level according to the classified class. A first step of measuring a signal spectrum within a measurement period of a user frequency band of the reverse frequency band; A second step of calculating an average of an absolute noise level in an unused frequency band of the reverse frequency bands; A third step of comparing the maximum measured value of the user frequency band with an average of the absolute noise level in the unused frequency band; A fourth step of analyzing the signal spectrum in the measurement section according to the result of the third step and comparing it with a predetermined value; A fifth step of alarming when the analysis result of the fourth step exceeds a predetermined value; And And a sixth step of adjusting the output of the signal transmitting equipment of the repeater or the base station according to the alarm. delete The method of claim 11, wherein the first step, And the measurement section is less than or equal to the frequency band used. The method of claim 11, wherein in the third step, And performing a fourth step when a difference between the maximum measured value of the user frequency band and the average of the absolute noise level in the unused frequency band is 5 dB or more. The method of claim 11, wherein the fourth step, The measurement section is divided into unit measurement sections, and sequential addresses are assigned to each unit measurement section, and a signal having a maximum measurement value and an address having the maximum measurement value among the signal measurement values of each unit measurement section. A first substep of collecting; And And performing a first substep at least one or more times, and performing a second noise step using the standard deviation of the maximum measured values obtained therefrom and the number of detections of the same address among the addresses. Reverse noise search method. The method of claim 15, wherein in the second substep: The predetermined value is a standard deviation of the maximum measured value is 5dB or more, the same address detection frequency is set to 80% or more of the total detection frequency, and when the predetermined value is exceeded, characterized in that the signal is determined as noise Reverse noise search method. The method of claim 11, wherein the fifth step, And classifying the strength of the noise into classes and determining an alarm level according to the classified classes.

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