WO2016108313A1

WO2016108313A1 - Device for detecting mobile communication signal and service frequency band

Info

Publication number: WO2016108313A1
Application number: PCT/KR2014/013104
Authority: WO
Inventors: 김형호; 김권; 신현수
Original assignee: 주식회사 쏠리드
Priority date: 2014-12-30
Filing date: 2014-12-31
Publication date: 2016-07-07
Also published as: KR20160082095A

Abstract

Provided is a device for detecting a mobile communication signal and a service frequency band, the device comprising: a frequency shifting unit consecutively shifting an input frequency of a mobile communication signal by as much as a pre-set frequency spacing; a correlation unit calculating the correlation between the mobile communication signal frequency-shifted by the frequency shifting unit and a reference pattern corresponding to a synchronization signal included in a target mobile communication signal to be detected; and a determining unit determining the existence or not of the target mobile communication signal on the basis of the results of the correlation calculation through the correlation unit.

Description

Mobile communication signal and service frequency band detection device

The present invention relates to an apparatus for detecting a mobile communication signal and a service frequency band, and more particularly, a mobile communication signal and a mobile station capable of easily detecting the changed mobile communication signal and the service frequency band when a mobile communication service that has been previously serviced is changed to another service. The present invention relates to a communication signal and a service frequency band detection device.

With the recent increase in the Long Term Evolution (LTE) service, the service frequency band according to the existing 3G communication methods (CDMA, GSM, WCDMA, etc.) may be changed to LTE.

The LTE-based mobile communication service is an orthogonal frequency division multiplexing (OFDM) -based communication service, and a system is implemented according to a communication method different from the existing 3G communication, and the frequency band used is also a service frequency band in the existing 3G communication. And may be different. Therefore, when the existing 3G communication service is changed to the LTE service, the system change reflecting the characteristics of the LTE service in terms of various signal processing in addition to the center frequency setting, filter bandwidth, gain control, amplifier control, CFR, etc. Is requested.

If the LTE service is provided as the system setting applied to the existing 3G communication service without changing the above system, the service signal may be deteriorated and distorted, thereby failing to provide a normal communication service.

Therefore, when the existing 3G communication service is changed to the LTE service, a method for checking whether such a change and the frequency band of the LTE service used according to the system itself is required.

An object of the present invention is to provide a mobile communication signal and a service frequency band detecting apparatus capable of easily detecting a changed mobile communication signal and its service frequency band when the existing mobile communication service is changed to another service.

According to an aspect of the invention, the frequency shifting unit for sequentially moving the frequency of the input mobile communication signal by a predetermined frequency interval; A correlator configured to perform a correlation operation between a mobile communication signal frequency shifted by the frequency shifting unit and a reference pattern corresponding to a synchronization signal included in a target mobile communication signal to be detected; And a determination unit determining whether the target mobile communication signal exists based on a correlation calculation result through the correlation unit.

In an embodiment, the frequency shifting unit may increase the reference moving frequency corresponding to the preset frequency interval by an integer multiple by an interval so that the input mobile communication signal is moved in one direction by the preset frequency interval for each preset period. You can.

In one embodiment, the frequency shifting unit,

A mixer for mixing the input mobile communication signal and a variable frequency signal; And a variable frequency oscillator for generating the variable frequency signal having a variable frequency and outputting the variable frequency signal to the mixer such that the frequency of the input mobile communication signal is sequentially shifted by the preset frequency interval at each preset period. have.

In one embodiment, the filter unit is disposed at the rear end of the frequency shifting unit and the front end of the correlation unit based on a signal transmission path, and extracts a signal having a predetermined frequency bandwidth among mobile communication signals output through the frequency shifting unit. It may include.

In one embodiment, the correlation unit may output a correlation result by performing a correlation operation between a signal corresponding to the frequency bandwidth set in the filter unit and a reference pattern corresponding to a synchronization signal included in a target mobile communication signal.

According to an embodiment, the filter unit may be implemented as a narrowband pass filter that passes a signal having a frequency bandwidth corresponding to a synchronization signal to be included in the target mobile communication signal according to a mobile communication service protocol.

In one embodiment, the target mobile communication signal may be a Long Term Evolution (LTE) service signal, and the synchronization signal may be a primary synchronization signal (PSS) included in the LTE service signal.

In one embodiment, the reference pattern corresponding to the synchronization signal may be a Zadoff-Chu sequence pattern, and may further include a signal pattern generator that generates the Zadoff-Chu sequence pattern.

The apparatus may further include a comparing unit configured to compare the correlation output power output according to the correlation operation of the correlation unit with a preset threshold power.

The determination unit may determine that the target mobile communication signal exists in the input mobile communication signal when the correlation output power is greater than or equal to the threshold power as a result of the comparison.

The band detector may further include a band detector configured to detect a service frequency bandwidth of the target mobile communication signal based on a frequency band detection result according to frequency scanning for each preset frequency interval or a correlation output power output through the comparison unit. can do.

In one embodiment, the determination unit,

The service frequency band of the target mobile communication signal may be detected based on the service frequency bandwidth of the target mobile communication signal detected by the band detector and the magnitude of the frequency shift by the frequency shifting unit.

In one embodiment, the determination unit,

The number of PSSs may be determined based on a comparison result by the comparator, and a service frequency band used by an LTE service may be detected based on the number of PSSs and a service frequency bandwidth detected by the band detector.

In one embodiment, the determination unit,

A frequency band in which the PSS is located in the LTE service signal based on a comparison result of the comparator, whether the PSS is present or not, and based on the magnitude of the frequency shift by the frequency shifting unit when the PSS is detected. And detect a center frequency of the LTE service signal based on the frequency band in which the PSS is located.

In one embodiment, the determination unit,

The service frequency band used by the LTE service may be detected based on the center frequency of the detected LTE service signal and the frequency bandwidth detected by the band detector.

According to an embodiment of the present invention, when a mobile communication service that has been previously serviced is changed to another service, the changed mobile communication signal and its service frequency band can be easily detected.

In addition, according to an embodiment of the present invention, in the process of changing the service of the conventional 3G communication services (CDMA, GSM, WCDMA, etc.) to the LTE service, whether or not the service is easily changed and / or the frequency band newly used in the LTE service By detecting it, it is possible to maintain the existing system and provide stable mobile communication service without deterioration of service.

1 is a view illustrating a topology of a distributed antenna system as one type of a signal distributed transmission system to which the present invention may be applied.

2 is a block diagram of one embodiment of a remote unit in a distributed antenna system to which the present invention may be applied.

3 is a block diagram showing a signal detection and service frequency band determination apparatus of mobile communication according to an embodiment of the present invention.

4 illustrates the location and band of a PSS in a time-frequency relationship of LTE service signals.

The present invention may be variously modified and have various embodiments, and specific embodiments will be illustrated in the drawings and described in detail with reference to the accompanying drawings. However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

In describing the present invention, when it is determined that the detailed description of the related known technology may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted. In addition, numerals (eg, first, second, etc.) used in the description process of the present specification are merely identification symbols for distinguishing one component from another component.

In addition, in the present specification, when one component is referred to as "connected" or "connected" with another component, the one component may be directly connected or directly connected to the other component, but in particular It is to be understood that, unless there is an opposite substrate, it may be connected or connected via another component in the middle.

In addition, the terms "~ unit", "~ group", "~ ruler", "~ module" as used herein refers to a unit for processing at least one function or operation, which means hardware or software or hardware and It can be implemented in a combination of software.

In addition, it is intended to clarify that the division of the components in the present specification is only divided by the main functions in charge of each component. That is, two or more components to be described below may be combined into one component, or one component may be provided divided into two or more for each function. Each of the components to be described below may additionally perform some or all of the functions of other components in addition to the main functions of the components, and some of the main functions of each of the components are different. Of course, it may be carried out exclusively by.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Hereinafter, as an application example to which a mobile communication signal and a service frequency band detection apparatus according to an embodiment of the present invention can be applied, a description will be given of a specific node unit (headend unit, hub unit, remote unit, etc.) in a distributed antenna system. . However, embodiments of the present invention may be similarly or similarly to a specific node unit (for example, a headend and a remote radio head (RRH) in a base station distributed system) in another signal distributed transmission system such as a base station distributed system, in addition to a distributed antenna system. Applicable When the mobile communication signal and the service frequency band detection apparatus according to the embodiment of the present invention are mounted on the headend side, system changes according to the detected information (that is, setting of the center frequency, filter bandwidth, gain control, amplifier control, Matter requiring system change reflecting the characteristics of LTE service such as CFR) can be delivered to the lower node unit. In this case, therefore, the implementation of the mobile communication signal and the service frequency band detection apparatus according to the embodiment of the present invention may be omitted in the lower node unit. In addition, the mobile communication signal and service frequency band detection apparatus according to an embodiment of the present invention can be applied to a digital RF repeater or an analog RF repeater, of course.

FIG. 1 is a diagram illustrating a topology of a distributed antenna system as one type of a signal distributed transmission system to which the present invention may be applied.

Referring to FIG. 1, a distributed antenna system (DAS) includes a base station interface unit (BIU) 10, a main unit 20, and an expansion node constituting a headend node of a distributed antenna system. (Hub Unit 30), which is an (Extention Node), and a plurality of Remote Units (RU) 40 disposed at each service location in a remote location. Such a distributed antenna system may be implemented as an analog DAS or a digital DAS, and in some cases, may be implemented as a hybrid thereof (ie, some nodes perform analog processing and others perform digital processing).

However, FIG. 1 illustrates an example of a topology of a distributed antenna system, and the distributed antenna system includes an installation area and an application field (for example, in-building, subway, hospital, Various topologies can be modified in consideration of the specificity of the stadium. For this purpose, the number of BIU 10, MU 20, HUB 30, RU 40 and the connection relationship between the upper and lower ends may also be different from FIG. In addition, in the distributed antenna system, the HUB 20 is utilized when the number of branches to be branched from the MU 20 to a star structure is limited compared to the number of RUs 40 required for installation. Therefore, the HUB 20 may be omitted when only a single MU 20 can adequately cover the number of RUs 40 required for installation or when a plurality of MUs 20 are installed.

Hereinafter, each node and its function in the distributed antenna system that can be applied to the present invention will be described in turn with reference to the topology of FIG. 1.

The base station interface unit (BIU) 10 serves as an interface between a base station transceiver system (BTS) such as a base station and the MU 20 in a distributed antenna system. Although FIG. 1 illustrates a case in which a plurality of BTSs are connected to a single BIU 10, the BIU 10 may be provided separately for each service provider, each frequency band, and each sector.

In general, since the RF signal (Radio Frequency signal) transmitted from the BTS is a high power signal, the BIU 10 is a signal having a power suitable for processing such a high power RF signal in the MU 20. It converts and delivers it to the MU 20. In addition, according to the implementation method, the BIU 10 receives a signal of a mobile communication service for each frequency band (or for each operator or sector) as shown in FIG. 1, and combines the signal with the MU 20. ) Can also be used

If the BIU 10 lowers the high power signal of the BTS to low power, and then combines each mobile communication service signal to the MU 20, the MU 20 combines the mobile communication service signals (hereinafter, referred to as these). (Referred to as a relay signal) to distribute branches by branch. In this case, when the distributed antenna system is implemented as a digital DAS, the BIU 10 converts the high power RF signal of the BTS into a low power RF signal, and an IF signal (Intermediate Frequency signal) for the low power RF signal. After conversion, the digital signal processing unit may be separated into a combine unit. Unlike the above, if the BIU 10 performs only a function of lowering the high power signal of the BTS to low power, the MU 20 may combine and distribute the transmitted relay signals for each branch.

As described above, the combined relay signal distributed from the MU 20 is passed through the HUB 20 or by the RU 40 on a branch-by-branch basis (see Branch # 1,… Branch #k,… Branch #N in FIG. 1). The RU 40 separates the received combined relay signal for each frequency band and performs signal processing (analog signal processing in the case of analog DAS and digital signal processing in the case of digital DAS). Accordingly, each RU 40 transmits a relay signal to a user terminal within its service coverage through a service antenna. In this case, a specific functional configuration of the RU 40 will be described later in detail with reference to FIG. 2.

In the case of FIG. 1, the BTS and the BIU 10 and the BIU 10 and the MU 20 are connected to each other by an RF cable, and the MU 20 to the lower end thereof are all connected by an optical cable. The signal transport medium between each node can be variously modified. For example, the BIU 10 and the MU 20 may be connected through an RF cable, but may also be connected through an optical cable or a digital interface. As another example, the MU 20 and the HUB 30 and the RU 40 directly connected to the MU 20 are connected by an optical cable, and cascaded RU 40 is connected to each other through an RF cable, a twisted cable, and a UTP. It may also be implemented in a way that is connected via a cable or the like. As another example, in another example, the RU 40 directly connected to the MU 20 may also be implemented in such a manner as to be connected through an RF cable, a twisted cable, a UTP cable, or the like.

However, hereinafter, it will be described with reference to FIG. Therefore, in the present embodiment, the MU 20, the HUB 30, and the RU 40 may include an optical transceiver module for all-optical conversion / photoelectric conversion, and, when connected to a node with a single optical cable, WDM ( Wavelength Division Multiplexing) device may be included. This may be clearly understood through the functional description of the RU 40 in FIG. 2 to be described later.

The distributed antenna system may be connected to an external management device (Network Management Server or System (NMS) of Figure 1) through a network, so that the administrator monitors the status and problems of each node of the distributed antenna system remotely through the NMS. And control the operation of each node remotely.

Here, the block diagram of FIG. 2 illustrates one implementation of a RU 40 in a digital DAS where node-to-node connectivity is via an optical cable. The block diagram of FIG. 2 shows only components related to the function of providing a service signal to a terminal in a service area through a forward path and processing a terminal signal received from a terminal in the service area through a reverse path.

In addition, the node unit to which the mobile communication signal and the service frequency band detection apparatus according to an embodiment of the present invention can be applied may be various, such as a headend, a HUB, an RRH in a base station distributed case, in addition to a remote unit to be described later. It is. However, hereinafter, it is assumed that the remote unit in the distributed antenna system for convenience and concentration of the description.

Referring to FIG. 2, the RU 40 may include an optical to electrical converter 50 and a serializer based on a downlink signal transmission path (ie, a forward path). / Deserializer (44), Deframer (52), Digital Signal Processing Unit (DSP) 70, Digital / Analog Converter (DAC) 54, Up Converter (56), PAU (Power) Amplification Unit) 58.

Accordingly, in the forward pass, the optical relay signal digitally transmitted through the optical cable is converted into an electrical signal (serial digital signal) by the optical / electric converter 50, and the serial digital signal is parallel digital by the SERDES 44. The digital signal is converted into a signal, and the parallel digital signal is reformatted by the deframer 52 to enable processing by frequency band in the digital signal processor 70. The digital signal processor 70 performs functions such as digital signal processing, digital filtering, gain control, and digital multiplexing for each relay band. The digital signal passed through the digital signal processing unit 70 is converted into an analog signal via a digital-to-analog converter 54 constituting the final stage of the digital part 84 based on the signal transmission path. At this time, the analog signal is an IF signal, and is up-converted to an analog signal of the original RF band through the up converter 56. The analog signal (that is, the RF signal) converted into the original RF band as described above is heavy through the PAU 58 and transmitted through a service antenna (not shown).

Based on the uplink signal propagation path (ie, reverse path), the RU 40 may include a low noise amplifier (LNA) 68, a down converter 66, and an analog / digital converter (ADC). 64, a digital signal processor (DSP) 70, a framer 62, a SERDES 44, and an electrical to optical converter 60.

Accordingly, in the reverse pass, the RF signal (ie, the terminal signal) received from the user terminal (not shown) within the service coverage via the service antenna (not shown) is low noise amplified by the LNA 68, which is a down converter ( 66 is frequency down-converted to the IF signal, and the converted IF signal is converted into a digital signal by the analog-to-digital converter 64 and transferred to the digital signal processor 70. The digital signal that has passed through the digital signal processor 70 is formatted by the framer 62 into a format suitable for digital transmission, which is converted into a serial digital signal by the SERDES 44, and the pre / optical converter 60 Is converted into an optical digital signal and transmitted to the upper end through the optical cable.

Also, although not clearly shown in FIG. 2, when the RUs 40 are cascaded to each other, as shown in the example of FIG. 1, the relay signal transmitted from the upper end is transmitted to the adjacent RU of the lower end cascaded. This can be done in the following way. For example, when transmitting an optical relay signal digitally transmitted from an upper end to an adjacent RU of a lower cascaded lower end, the optical relay signal digitally transmitted from an upper end is an optical / electric converter 50-> SERDES 44-. > Deframer 52-> framer 62-> SERDES 44-> pre / optical converter 60 and then to adjacent RUs. This will be clearly understood through FIG. 4 to be described later.

In FIG. 2, the SERDES 44, the deframer 52, the framer 62, and the digital signal processor 70 may be implemented as a field programmable gate array (FPGA). In addition, although the SERDES 44 and the digital signal processor (DSP) 70 are shared in the downlink and uplink signal transmission paths in FIG. 2, they may be separately provided for each path. In addition, although the optical / electric converter 50 and the electrical / optical converter 60 are shown separately in FIG. 2, this is a single optical transceiver module (eg, a single small form factor pluggable (SFP) (FIG. 2). Reference numeral 82 of FIG. 2).

In the above, with reference to FIGS. 1 and 2, one type of topology of a distributed antenna system and one configuration example of an RU have been described. In particular, FIG. 2 illustrates the RU in the digital DAS digitally transmitted through the transmission medium. However, the mobile communication signal and the service frequency band detection apparatus according to an embodiment of the present invention can be applied to an analog transmission system such as an analog DAS (that is, a distributed antenna system that is analog transmitted through a transmission medium) in addition to the digital DAS.

3 is a block diagram illustrating a signal detection and service frequency band determination apparatus of mobile communication according to an embodiment of the present invention.

Referring to FIG. 3, the apparatus for detecting a mobile communication signal and a service frequency band according to an embodiment of the present invention includes a frequency shifting unit 110, a filter unit 130, a correlation unit 150, and a signal pattern generation unit 160. ), The determination unit 170 may be included.

The frequency shifting unit 110 may sequentially move the frequency of the input mobile communication signal (see FIG. 3A) by a predetermined frequency interval. In this case, the sequential movement by a preset frequency interval may be performed every preset period.

To this end, the frequency shifting unit 110 moves the reference mobile frequency f _s corresponding to the preset frequency interval so that the frequency of the input mobile communication signal is shifted in one direction by the preset frequency interval for each preset period. Can be sequentially increased by an integer multiple. For example, the frequency shifting unit 110 shifts and outputs the input mobile communication signal by the reference moving frequency f _s , and then outputs the input mobile communication signal twice the reference mobile frequency in the next period. It can be output after moving (2f _s ).

According to the embodiment illustrated in FIG. 3, the frequency shifting unit 110 may include a variable frequency oscillator 111 generating a variable frequency signal having a variable frequency, a variable frequency signal generated from the variable frequency oscillator 111, and a variable frequency signal generated from the variable frequency oscillator 111. It may include a mixer 113 for mixing (mixing) the input mobile communication signal. In this case, the variable frequency oscillator 111 may generate a variable frequency signal such that the frequency of the input mobile communication signal is sequentially moved in one direction by the preset frequency interval at each preset period. According to the embodiment of Figure 3, the variable frequency oscillator 111 may be implemented as a NCO (Numerically Controlled Oscillator).

The filter unit 130 extracts only a signal having a specific frequency bandwidth from the signal output from the frequency shifting unit 110. According to the embodiment of FIG. 3, the filter unit 130 is disposed at the rear end of the frequency shifting unit 110 and the front end of the correlation unit 150 on the basis of the signal transmission path to identify the mobile communication signal shifted in frequency. Only bandwidth signals are extracted.

However, in the exemplary embodiment of the present invention, the filter unit 130 may be omitted. Since the filter unit 130 is provided to further increase the correlation efficiency through the correlator 150, the target mobile communication signal to be detected according to the correlation result by the correlator 150 even if the filter unit 130 is omitted. This is because the synchronization signal of? Can be detected. However, according to the embodiment of FIG. 3, the filter unit 130 corresponds to the frequency bandwidth of the synchronization signal of the target mobile communication signal to be detected in order to increase the efficiency of the correlation operation through the correlation unit 150. The case of implementing a narrow band pass filter (Narrow Band BPF) having a bandwidth is shown.

As will be described later, when the mobile communication signal to be detected is an LTE service signal, a synchronization signal in the LTE service signal includes a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) as shown in FIG. 4. 4 is a diagram illustrating the location and band of the PSS in the time-frequency relationship of the LTE service signal. Referring to FIG. 4, the PSS and the SSS are repeated every 5 ms period as a synchronization signal in the LTE service signal. In addition, the PSS and SSS have a bandwidth of 1.08 MHz.

Therefore, according to an embodiment of the present invention, when the method of detecting the PSS as the synchronization signal is employed to detect the LTE service signal as the target mobile communication signal, the narrowband pass filter is set to 1.08 MHz, which is the bandwidth of the PSS signal. It can be set to have a corresponding bandwidth. In this case, the signal passing through the filter unit 130 and transmitted to the correlation unit 150 corresponds to a pass band by the narrowband pass filter among the mobile communication signals shifted in frequency by the frequency shifting unit 110 and its bandwidth. Will be the signal of the band.

The correlation unit 150 performs a correlation operation between the signal extracted by the filter unit 130 and the reference pattern corresponding to the synchronization signal included in the target mobile communication signal to be detected. If the synchronization signal does not exist in the signal of the band extracted by the filter unit 130, the correlation result according to the correlation operation in the correlation unit 150 may output a very low correlation value. On the contrary, when the synchronization signal is present in the signal of the band extracted by the filter unit 130, the correlation operation performed by the correlation unit 150 may output a correlation value having a very high value.

The reference pattern to be used in the correlation operation of the correlation unit 150 may be generated by the signal pattern generation unit 160 and transferred to the correlation unit 150. The signal pattern generator 160 generates a reference pattern corresponding to the synchronization signal of the target mobile communication signal to be detected. However, when the target mobile communication signal to be detected is fixed, the signal pattern generator 160 may be omitted. This is because the reference pattern may be stored in the correlator 150 itself and used.

In an embodiment, when the target mobile communication signal to be detected is the LTE service signal as described above, the signal pattern generator 160 may generate a reference pattern corresponding to the pattern of the PSS signal. Since the PSS signal includes the Zadoff-Chu sequence, according to the embodiment of FIG. 3, the signal pattern generator 160 generates the Zadoff-Chu sequence as a reference pattern.

The determination unit 170 detects the existence of the target mobile communication signal to be detected and the service frequency band based on the correlation calculation result by the correlation unit 150. To this end, the determination unit 170 may include a comparator 171, a band detector 173, and a frequency band determiner 175 as shown in FIG. 3. Hereinafter, each component will be described in detail.

The comparison unit 171 compares the correlation output power output according to the correlation operation of the correlation unit 150 with a preset threshold power. Here, the threshold power may be set in consideration of the output power output according to a correlation operation between the sync signal and the reference pattern by including the sync signal in the mobile communication signal input to the correlator 150. That is, the threshold power is set so as to confirm the existence of the target mobile communication signal to be detected when the correlation output power is greater than or equal to the threshold power.

Accordingly, the determination unit 170 may check whether the target mobile communication signal to be detected exists in the input mobile communication signal based on the comparison result of the comparison unit 171. For example, when the target mobile communication signal to be detected is an LTE service signal, the determination unit 170 may input the mobile communication when there is a correlation output power above the threshold power according to the comparison result of the comparison unit 171. The LTE service signal may be detected in the signal.

According to the comparison result of the comparison unit 171, if there are a plurality of correlation output powers above the threshold power due to different time differences, the target mobile communication signal may be serviced in plurality in different frequency bands. Indicates. For example, in the case of the LTE service signal, since only one PSS signal exists per service, the existence of a plurality of correlated output powers above the threshold power means that a plurality of LTE services are provided in different frequency bands. Accordingly, the determination unit 170 may also detect the number of LTE services included in the input mobile communication signal by checking the number of PSSs according to the comparison result of the comparison unit 171.

In addition, the determination unit 170 may check the service frequency bandwidth used by the detected target mobile communication signal. This may be detected by the band detector 173 in the determiner 170. The detection of the service frequency bandwidth of the target mobile communication signal may be performed by the following method. For example, the band detector 170 may include a signal frequency range in which the output correlation output power continuously represents a value greater than or equal to a preset threshold power based on the correlation output power according to the correlation calculation result of the correlation unit 150. And detect the service frequency bandwidth of the target mobile communication signal. As another example, the band detector 170 may detect the service frequency bandwidth of the target mobile communication signal through a separate frequency scanning process irrespective of the correlation output power according to the correlation calculation result of the correlation unit 150 described above. For example, frequency scanning may be performed by a preset frequency bandwidth interval (eg 200 KHz) to detect a frequency range in which the power of the input signal is maintained above a predetermined value, thereby detecting the service frequency bandwidth of the target mobile communication signal. have. In addition, when the number of detected PSS is two and the total service frequency bandwidth detected by the band detector 173, which will be described later, is 20 MHz, it can also be determined that two LTE services of 10 MHz service frequency bandwidth are provided.

As described above, when the service frequency bandwidth of the target mobile communication signal is detected, the determination unit 170 (more specifically, the frequency band determination unit 175) refers to the detected service frequency bandwidth to service the target mobile communication signal. Frequency bands can also be determined. Hereinafter, a method of determining a service frequency band of a target mobile communication signal will be described. In the following description, a case of the LTE service signal will be described for convenience of description.

According to an exemplary embodiment, the determination unit 170 inverts the PSS by referring to the magnitude of the frequency shift by the frequency shifting unit 110 when the PSS signal is detected according to the comparison result of the comparison unit 171. It is possible to detect the original frequency band where the signal is actually located in the LTE service signal. As such, when the original frequency band where the PSS signal is actually located is identified, the center frequency of the corresponding LTE service signal may also be checked. This is because the center frequency exists at a position separated by a predetermined frequency interval in the frequency band of the PSS. When the center frequency of the LTE service signal is identified, the service frequency band of the LTE service may be detected by considering the service frequency bandwidth of the LTE service previously detected by the band detector 173.

According to another exemplary embodiment, the determination unit 170 may determine the service frequency bandwidth of the target mobile communication signal detected by the band detection unit 173, the size of the frequency shift by the frequency shifting unit 110, and the filter unit 130. By inverting the frequency band with reference to the pass band, the service frequency band of the target mobile communication signal may be detected.

As described above, the mobile communication signal and the service frequency band detection apparatus according to an embodiment of the present invention target frequency communication to be detected through a correlation operation on the synchronization signal included in the mobile communication signal while frequency shifting the input signal The presence of signals and the service frequency band can be easily identified. Therefore, according to the mobile communication signal and the service frequency band detection apparatus according to an embodiment of the present invention, even when a service change occurs, such as the existing 3G communication service is changed to LTE service, the system change corresponding to the confirmed service change ( As the service frequency band changes, the necessary center frequency setting, filter bandwidth, gain control, amplifier control, CFR setting, etc. can be performed by itself. According to this, in particular, even when the existing 3G communication service is changed to the LTE service, it is possible to maintain the existing system as it is, but stable mobile communication service without service deterioration through system change.

Although the above has been described with reference to embodiments of the present invention, those skilled in the art may variously modify the present invention without departing from the spirit and scope of the present invention as set forth in the claims below. And can be changed easily.

Claims

A frequency shifting unit which sequentially shifts the frequency of the input mobile communication signal by a predetermined frequency interval;

A correlator configured to perform a correlation operation between a mobile communication signal frequency shifted by the frequency shifting unit and a reference pattern corresponding to a synchronization signal included in a target mobile communication signal to be detected; And

Determination unit for determining the presence of the target mobile communication signal based on the correlation calculation result through the correlation unit

Mobile communication signal and service frequency band detection apparatus comprising a.
The method of claim 1,

The frequency shifting unit may increase the reference mobile frequency corresponding to the preset frequency interval by an integer multiple by an integer multiple so that the input mobile communication signal is moved in one direction by the preset frequency interval for each preset period. And a service frequency band detection device.
The method of claim 2,

The frequency shifting unit,

A mixer for mixing the input mobile communication signal and a variable frequency signal; And a variable frequency oscillator for generating the variable frequency signal having a variable frequency and outputting the variable frequency signal to the mixer such that the frequency of the input mobile communication signal is sequentially shifted by the preset frequency interval at each preset period. Mobile communication signal and service frequency band detection device.
The method of claim 1,

And a filter unit arranged at a rear end of the frequency shifting unit and a front end of the correlation unit based on a signal transmission path, and extracting a signal having a predetermined frequency bandwidth among the mobile communication signals output through the frequency shifting unit. Signal and service frequency band detection device.
The method of claim 4, wherein

The correlation unit detects a mobile communication signal and a service frequency band by outputting a correlation result by performing a correlation operation between a signal corresponding to a frequency bandwidth set in the filter unit and a reference pattern corresponding to a synchronization signal included in a target mobile communication signal. Device.
The method of claim 4, wherein

The filter unit is implemented as a narrowband pass filter for passing a signal of the frequency bandwidth corresponding to the synchronization signal to be included in the target mobile communication signal in accordance with the mobile communication service protocol, mobile communication signal and service frequency band detection device.
The method of claim 4, wherein

The target mobile communication signal is a Long Term Evolution (LTE) service signal, and the synchronization signal is a primary synchronization signal (PSS) included in the LTE service signal, the mobile communication signal and the service frequency band detection device.
The method of claim 7, wherein

The reference pattern corresponding to the synchronization signal is a Zadoff-Chu sequence pattern,

And a signal pattern generator for generating the Zadoff-Chu sequence pattern.
The method of claim 7, wherein

The apparatus may further include a comparing unit configured to compare a correlation output power output according to a correlation operation of the correlation unit with a preset threshold power.

And the determining unit determines that the target mobile communication signal exists in the input mobile communication signal when the correlation output power is equal to or greater than the threshold power.
The method of claim 9,

The mobile communication signal further includes a band detector configured to detect a service frequency bandwidth of the target mobile communication signal based on a frequency band detection result according to frequency scanning for each preset frequency interval or a correlation output power output through the comparison unit. And a service frequency band detection device.
The method of claim 10,

The determination unit,

A mobile communication signal and a service frequency band for detecting a service frequency band of the target mobile communication signal based on the service frequency bandwidth of the target mobile communication signal detected by the band detector and the magnitude of the frequency shift by the frequency shifting unit. Detection device.
The method of claim 10,

The determination unit,

Determining the number of PSSs based on a comparison result by the comparing unit, and detecting a service frequency band used by the LTE service based on the number of PSSs and the service frequency bandwidth detected by the band detector. Signal and service frequency band detection device.
The method of claim 10,

The determination unit,

A frequency band in which the PSS is located in the LTE service signal based on a comparison result of the comparator, whether the PSS is present or not, and based on the magnitude of the frequency shift by the frequency shifting unit when the PSS is detected. And detecting a center frequency of the LTE service signal on the basis of the frequency band in which the PSS is located.
The method of claim 13,

The determination unit,

And a service frequency band used by the LTE service on the basis of the detected center frequency of the LTE service signal and the frequency bandwidth detected by the band detector.