JP2011182101A - Base station evaluation device and received frequency control method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To normally appropriately set the received frequency area of a receiving part in response to a set carrier frequency and measurement condition without requiring complicated adjustment work concerning a device for evaluating a base station device corresponding to multi-carrier and multi-standard. <P>SOLUTION: A received frequency control means 50 acquires a frequency range to be minimally required for measurement, based on respective carrier frequencies and measurement item information set by a setting part 30, calculates the frequency f<SB>LOC</SB>of a local signal for converting the center frequency of the frequency range into the passage center frequency of an intermediate frequency band of a wide band receiving part 22, and sets the frequency in a wide band receiving part 22. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a technique for analyzing and evaluating a signal output from a base station apparatus of a mobile communication system such as a mobile phone, and in particular, a plurality of different from a multicarrier system that performs simultaneous communication in a plurality of different frequency bands. The present invention relates to a technique for enabling efficient evaluation of a base station apparatus compatible with a multi-standard method corresponding to a communication standard.

  In a mobile communication system such as a mobile phone, communication is performed by time-division multiplexing a plurality of user signals in a frequency band (carrier frequency) for communication between a base station and a terminal, but the number of users is large. Then, it becomes impossible to multiplex with one carrier frequency. For this reason, one communication company has increased the number of available users by using a plurality of carrier frequencies.

  Correspondingly, a so-called multi-carrier method is adopted in which the base station also performs communication simultaneously using a plurality of carrier frequencies.

  In addition, with the shift of the modulation method of terminals, etc., it is also required that one communication carrier communicates with different communication standards (for example, GSM and W-CDMA), and there are a plurality of base stations to cope with this. A so-called multi-standard method is employed in which signals are transmitted simultaneously using signals of different communication standards. In recent years, a base station apparatus compatible with multi-carrier and multi-standard is required.

  Therefore, a wireless standard for operating a plurality of systems in the same frequency band is defined as Multi-Standard Radio (MSR) Base Station (BS) in 3GPP TS 37.104. The frequency band is as shown in FIG.

  In FIG. 6, for example, in the frequency bands defined by the base station output (Downlink), for example, in the frequency bands of 869 to 894 MHz and 925 to 960 MHz, MSR and E-UTRA (LTE) And three different systems are used: UTRA (W-CDMA) and GSM / EDGE.

  Therefore, in order to evaluate the base station apparatus that uses the carrier frequencies in the frequency bands of 869 to 894 MHz and 925 to 960 MHz for communication, it is necessary to measure each carrier frequency signal according to a different system. However, the conventional evaluation apparatus for mobile communication devices, for example, as described in the following Patent Document 1, selectively receives a signal of one carrier frequency (single carrier) and performs processing necessary for the evaluation. Therefore, when performing multicarrier measurement, a series of tests necessary for evaluation of one carrier frequency is performed, and then the next carrier frequency is transferred to perform the same test. There is a problem that it takes time and labor.

  In addition, due to the measurement principle, there is a problem that it is impossible to grasp the mutual influence between bands when a plurality of carrier frequencies are used simultaneously.

JP 2007-19741 A

  As a technique for solving the above problem, signal components of a plurality of carrier frequencies to be measured are collectively received by a heterodyne wideband receiver and converted into an intermediate frequency band, and the waveform of the signal in the intermediate frequency band A method is conceivable in which data is acquired and stored for a certain period of time, and signal components of individual carrier frequencies are extracted from the stored waveform data and analyzed.

  However, when actually configuring the evaluation apparatus of the above method, if the measurement conditions can be arbitrarily set for each of a plurality of carrier frequencies to be measured and the frequencies, a plurality of measurement objects can be set in the intermediate frequency band of the receiving unit. An operation for adjusting the signal component of the carrier frequency to be surely entered is necessary, and when the carrier frequency to be measured is large, the adjustment work becomes complicated.

  In addition, depending on the measurement item, it is necessary to measure the signal component leaking to the adjacent band separated from the signal component band of the carrier frequency to be measured, and not only the measurement target carrier frequency but also the measurement item is received. Adjustment of the frequency becomes necessary, and the work is further complicated.

  The present invention solves this problem and, in an apparatus for evaluating a base station apparatus compatible with multi-carrier and multi-standard, a receiving unit according to a set carrier frequency and measurement conditions without complicated adjustment work. It is an object of the present invention to provide a base station evaluation apparatus and a base station evaluation method that always properly control the reception frequency region of the above.

In order to achieve the above object, a base station evaluation apparatus according to claim 1 of the present invention comprises:
Wideband reception that receives a signal including a plurality of different carrier frequencies used for communication by the base station apparatus to be evaluated, mixes the signal with a local signal, and converts the signal into an intermediate frequency band that covers the plurality of different carrier frequencies Section (22), an A / D converter (23) for sampling the signal output from the broadband receiving section and converting it into digital waveform data, and waveform data for storing the waveform data converted by the A / D converter A reception storage unit (21) having a memory (24) and acquiring waveform data of a signal output by the base station device at a predetermined time;
Analyzes the waveform data stored in the reception storage unit, detects a signal inserted in a desired time slot in the frame of each carrier frequency, and uses a modulation scheme and measurement items set in advance for the slot. An analysis unit (25) for performing signal demodulation and measurement based on the
A setting unit (30) for causing the analysis unit to set modulation scheme information and measurement item information for each carrier frequency and each slot in the frame for each carrier frequency;
Based on each carrier frequency set by the setting unit and measurement item information, a minimum frequency range (f1 to f2) necessary for measurement is obtained, and the center frequency of the frequency range becomes the passing center frequency of the intermediate frequency band. Reception frequency control means (50) for calculating the frequency of the local signal of the wideband receiving unit to be converted and setting the frequency in the wideband receiving unit.

Further, the reception frequency control method of the base station evaluation apparatus of the present invention is:
Wideband reception that receives a signal including a plurality of different carrier frequencies used for communication by the base station apparatus to be evaluated, mixes the signal with a local signal, and converts the signal into an intermediate frequency band that covers the plurality of different carrier frequencies Section (22), an A / D converter (23) for sampling the signal output from the broadband receiving section and converting it into digital waveform data, and waveform data for storing the waveform data converted by the A / D converter A reception storage unit (21) having a memory (24) and acquiring waveform data of a signal output by the base station device at a predetermined time;
Analyzes the waveform data stored in the reception storage unit, detects a signal inserted in a desired time slot in the frame of each carrier frequency, and uses a modulation scheme and measurement items set in advance for the slot. An analysis unit (25) for performing signal demodulation and measurement based on the
A reception frequency control method for a base station evaluation apparatus, comprising: a setting unit (30) configured to set modulation method information and measurement item information for each carrier frequency and each slot in a frame for each carrier frequency to the analysis unit. And
Obtaining a minimum frequency range (f1 to f2) required for measurement from the carrier frequency set by the setting unit and measurement items (S1 to S7);
Calculating a frequency of the local signal for converting a center frequency of the obtained frequency range into a passing center frequency of the intermediate frequency band of the broadband receiving unit, and setting the frequency to the broadband receiving unit (S8); Is included.

  As described above, in the present invention, the minimum frequency range (f1 to f2) necessary for measurement is obtained from the measurement items for the set carrier frequency and the measurement target time slot in the frame, and the center frequency of the frequency range is determined as the center frequency. Since the frequency of the local signal is calculated and set so that it is converted to the center frequency of the intermediate frequency band of the wideband receiver, there is no need for complicated adjustment of the received frequency for any setting, and always correct measurement Can be done.

Configuration diagram of an embodiment of the present invention The figure for demonstrating the operation | movement of the principal part of embodiment. The flowchart for demonstrating the operation | movement of the principal part of embodiment. The figure for demonstrating the operation | movement of the principal part of embodiment. The figure for demonstrating the operation | movement of the principal part of embodiment. The figure showing the relationship between the frequency band which a base station apparatus uses, and the system used for communication

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows the configuration of a base station evaluation apparatus 20 to which the present invention is applied.

  In FIG. 1, the reception storage unit 21 includes a broadband reception unit 22, an A / D converter 23, and a waveform data memory 24.

  The wideband receiving unit 22 has a wide reception band including a plurality of different carrier frequencies used for communication by the evaluation target base station apparatus 1 corresponding to multicarrier and multistandard (for example, 869 to 894 MHz, 925 to 960 MHz as described above). Frequency band), and the signal components of a plurality of carrier frequencies designated by the setting unit 30 described later are collectively received among the signals in the reception band.

Broadband receiving unit 22 includes a mixer 22a, includes a local signal generator 22b and the intermediate frequency filter 22c, and a local signal _{S LOC} output from the input signal _{S IN} and the local signal generator 22b to mix fed to the mixer 22a, One of the sum and difference components (here, the difference component) is extracted by the intermediate frequency filter 22c, and the band of the intermediate frequency filter 22c may be designated as a measurement target. It has a width W necessary to pass all the signal components of the carrier frequency.

  For example, when there is a possibility that the entire reception band of 925 to 960 MHz may be designated as a measurement target, a width of at least 960-925 = 35 MHz is required.

The frequency _{f LOC} of the local signal _{S LOC,} if the passing center frequency of the intermediate frequency filter 22c and _{f IF,} actually all _{f IF} ± signal components of the carrier frequency specified as the measurement object by setting section 30 Any value can be used as long as it is heterodyne converted into the intermediate frequency band of W / 2. | (925 + 960) / 2−f so that the signal components of the entire reception band of 925 to 960 MHz can be collectively converted into the intermediate frequency band. _{If LOC} | = f _IF , any carrier frequency within the reception band can be specified with a fixed local frequency f _LOC . Taking numerical examples, f _IF = 200 MHz and f _LOC = 742.5 MHz (or 1142.5 MHz).

  However, the carrier frequency (channel) to be measured is an item that is arbitrarily specified by the measurer. If the specified carrier is concentrated only on one end of the reception band, the frequency component of the signal component is converted to the intermediate frequency. This is concentrated on the edge of the pass band of the filter 22c, which is susceptible to the characteristics of the filter edge (amplitude and phase fluctuations) and is undesirable.

  In order to prevent this, it is possible to set the local frequency based on the carrier frequency specified by the measurer, but in addition to the above-mentioned carrier frequency, in addition to the slot designation and measurement item designation operation, If a local frequency setting operation is added, the operation becomes very complicated.

Therefore, in this base station evaluation apparatus 20, the reception frequency control means 50 automatically sets the frequency f _LOC (that is, the reception frequency) of the local signal output from the local signal generator 22b.

The reception frequency control means 50 obtains a minimum frequency range f1 to f2 necessary for measurement based on each carrier frequency set by the setting unit 30 and measurement item information, and a center frequency (f1 + f2) / f of the frequency range. The frequency f _{LOC of the} local signal is set so that 2 is converted to the passing center frequency f _IF in the intermediate frequency band.

That is, for easy understanding, if the lower heterodyne having a local frequency lower than the input signal frequency is used, the lower limit frequency f1 and the upper limit frequency f2 are determined according to the upper and lower limits of the carrier frequency arbitrarily specified by the measurer and the measurement item. Whereas
f _LOC = (f1 + f2) / 2−f _IF
Is obtained, and the frequency information is set in the local signal generator 22b to generate a local signal having the frequency f _LOC . For upper heterodyne,
f _LOC = (f1 + f2) / 2 + f _IF
Find and set the local frequency at which

  The lower limit frequency f1 and the upper limit frequency f2 are determined in consideration of the case where the measurement item of adjacent channel leakage is specified for the lower limit and the upper limit carrier frequency.

  As a result, for example, as shown in FIG. 2A, even when the carrier frequencies fc1 to fcn to be measured are biased toward the low frequency side of the entire reception band, the intermediate frequency as shown in FIG. The signals are gathered and output in the vicinity of the center of the band, and are not easily affected by fluctuations in the amplitude characteristics and phase characteristics of the filter edges. FIG. 2 shows the case of the lower heterodyne. However, in the case of the upper heterodyne, the arrangement of the signal components converted to the intermediate frequency band is inverted with respect to the case of FIG.

The signal S _IF converted to the intermediate frequency band is sampled by the A / D converter 23 at a predetermined frequency (more than twice the upper limit frequency of the intermediate frequency band), converted into a digital signal sequence D (k), and a waveform. It is stored in the data memory 24 for a certain time.

  The analysis unit 25 analyzes the waveform data stored in the waveform data memory 24 of the reception storage unit 21, detects a signal inserted in a desired time slot in the frame of each carrier frequency, Based on the set modulation method and measurement item, signal demodulation and measurement are performed, and the result is displayed on the display unit 40.

  Here, the analysis unit 25 performs an analysis process according to the information specified by the setting unit 30 described later.

  The setting unit 30 displays the information necessary for setting on the display unit 40 in accordance with the operation of the operation unit 45, and causes the analysis unit 25 to display modulation scheme information and measurement items for each slot in each carrier frequency frame. This is for setting information.

  The information to be specified here is a measurement item such as a carrier frequency, a frame and slot of a signal component of the carrier frequency, a modulation method such as GMSK or 8PSK, and Power, Modulation (modulation error), ORFS (adjacent channel leakage), etc. The demodulation processing based on the designated modulation method is performed on the desired slot of the desired frame of the signal component of the designated carrier frequency, and the designated item is measured for the result.

  The analysis unit 25 refers to the information specified by the setting unit 30, and converts the signal components of the carrier frequencies fc1, fc2,... (Actually converted to the intermediate frequency band from the waveform data stored in the waveform data memory 24). Signal component) is extracted by digital filter processing, a signal inserted in a desired time slot in a signal frame of each carrier frequency is detected, and based on the modulation method and measurement item specified for that slot The signal demodulation process and various measurement processes are performed, and the results are displayed on the display unit 40.

  In addition, the reception frequency control means 50 described above determines the carrier frequencies fc1, fc2,... Specified by the setting unit 30, the modulation scheme (specifies the occupied bandwidth), and the presence / absence of adjacent channel leakage. Determine the reception frequency.

  FIG. 3 is a flowchart showing a processing procedure of the reception frequency control means 50. The operation of the embodiment of the present invention will be described below based on this flowchart.

  First, it is checked whether there is an adjacent channel leakage (ORFS or ACLR) item in the measurement item of the highest frequency among the carrier frequencies (channels) designated as the measurement object by the setting unit 30 (S1).

  When there is an adjacent channel leakage item, as shown in FIG. 4A, the upper limit frequency f2 ′ required for the measurement of the maximum carrier frequency is set to the frequency width Wa required for the adjacent channel leakage measurement and a predetermined value. The upper limit frequency f2 is determined by adding the margin α (S2). When there is no adjacent channel leakage item, as shown in FIG. 4 (b), a predetermined margin β is added to the upper limit frequency f2 ′ necessary for the measurement of the highest carrier frequency, and the upper limit frequency is set. Let it be f2 (S3).

  Next, it is checked whether there is an adjacent channel leakage (ACLR or ORFS) item in the measurement item of the lowest frequency among the carrier frequencies (channels) designated as the measurement object by the setting unit 30 (S4).

  If there is an item of adjacent channel leakage, as shown in FIG. 5A, the frequency width Wa required for measurement of adjacent channel leakage from the lower limit frequency f1 ′ required for measurement of the minimum frequency of the carrier frequency. Then, the lower limit frequency f1 is determined by subtracting the sum of the predetermined margin α (S5). When there is no adjacent channel leakage item, as shown in FIG. 5B, a predetermined margin β is subtracted from the lower limit frequency f1 ′ necessary for measurement of the lowest carrier frequency to obtain the lower limit frequency f1. (S6).

Then, the center value fm = (f1 + f2) of the lower limit frequency f1 and an upper frequency limit f2 / 2 The calculated (S7), the local frequency _{f LOC} for the center value fm is converted to central pass frequency _{f IF} of the intermediate frequency band _Is calculated by f _LOC = fm−f _IF (or f _LOC = fm + f _IF ), and the frequency information is set in the local signal generator 22b (S8).

As described above, in the base station evaluation apparatus 20 according to the embodiment, the minimum frequency range (f1 to f2) necessary for the measurement is determined from the measurement items for the carrier frequency set by the setting unit 30 and the measurement target time slot in the frame. ) And the frequency f _{LOC of the} local signal is automatically set so that the center frequency fm of the frequency range is converted to the center frequency f _IF of the intermediate frequency band of the wideband receiver 22. This eliminates the need for complicated adjustment of the reception frequency, and correct measurement can always be performed.

  DESCRIPTION OF SYMBOLS 20 ... Base station evaluation apparatus, 21 ... Reception storage part, 22 ... Broadband receiving part, 22a ... Mixer, 22b ... Local signal generator, 22c ... Intermediate frequency filter, 23 ... A / D converter , 24... Waveform data memory, 25... Analysis unit, 30... Setting unit, 40... Display unit, 45.

Claims (2)

Wideband reception that receives a signal including a plurality of different carrier frequencies used for communication by the base station apparatus to be evaluated, mixes the signal with a local signal, and converts the signal into an intermediate frequency band that covers the plurality of different carrier frequencies Section (22), an A / D converter (23) for sampling the signal output from the broadband receiving section and converting it into digital waveform data, and waveform data for storing the waveform data converted by the A / D converter A reception storage unit (21) having a memory (24) and acquiring waveform data of a signal output by the base station device at a predetermined time;
Analyzes the waveform data stored in the reception storage unit, detects a signal inserted in a desired time slot in the frame of each carrier frequency, and uses a modulation scheme and measurement items set in advance for the slot. An analysis unit (25) for performing signal demodulation and measurement based on the
A setting unit (30) for causing the analysis unit to set modulation scheme information and measurement item information for each carrier frequency and each slot in the frame for each carrier frequency;
Based on each carrier frequency set by the setting unit and measurement item information, a minimum frequency range (f1 to f2) necessary for measurement is obtained, and the center frequency of the frequency range becomes the passing center frequency of the intermediate frequency band. A base station evaluation apparatus comprising: reception frequency control means (50) for calculating a frequency of a local signal of the broadband receiving unit to be converted and setting the frequency in the broadband receiving unit. Wideband reception that receives a signal including a plurality of different carrier frequencies used for communication by the base station apparatus to be evaluated, mixes the signal with a local signal, and converts the signal into an intermediate frequency band that covers the plurality of different carrier frequencies Section (22), an A / D converter (23) for sampling the signal output from the broadband receiving section and converting it into digital waveform data, and waveform data for storing the waveform data converted by the A / D converter A reception storage unit (21) having a memory (24) and acquiring waveform data of a signal output by the base station device at a predetermined time;
Analyzes the waveform data stored in the reception storage unit, detects a signal inserted in a desired time slot in the frame of each carrier frequency, and uses a modulation scheme and measurement items set in advance for the slot. An analysis unit (25) for performing signal demodulation and measurement based on the
A reception frequency control method for a base station evaluation apparatus, comprising: a setting unit (30) configured to set modulation method information and measurement item information for each carrier frequency and each slot in a frame for each carrier frequency to the analysis unit. And
Obtaining a minimum frequency range (f1 to f2) required for measurement from the carrier frequency set by the setting unit and measurement items (S1 to S7);
Calculating a frequency of the local signal for converting a center frequency of the obtained frequency range into a passing center frequency of the intermediate frequency band of the broadband receiving unit, and setting the frequency to the broadband receiving unit (S8); A reception frequency control method for a base station evaluation apparatus.

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