KR101891910B1 - Waveform Design for QAM-FBMC Systems Considering Time Domain Localization - Google Patents

Abstract

A filter and its design method suitable for reference and multipath fading channel environment for efficient filter design in QAM-FBMC system are presented. In the filter bank-based multi-carrier system proposed in the present invention, the filter design method considering the localization of the time domain applies a filter applying a frequency shift to each of a plurality of subcarriers as a pulse forming filter, Filters are matched, defining the total pulse shape, calculating the total interference power in a plurality of subcarriers to define a self-SIR of the QAM-FBMC transmission signal for the normalized value, a discrete-time Fourier transform The power distribution density PSD of the QAM-FBMC transmission signal is determined by DTFT and the relationship between the filter coefficient and the fall-off rate of the DTFT of the filter is determined by the differentiability of the continuity of the filter Perform the localization in the frequency domain through the steps of the filter, the tap and the pole-off rate, and use the normalized time and the normalized energy in the time domain And a step of performing a screen.

Description

[Background Art] [0002] In a multi-carrier system based on a filter bank, a filter design considering time domain localization is proposed.

FIELD OF THE INVENTION The present invention relates to filters for designing efficient filters in a QAM-FBMC system and filters suitable for multipath fading channel environments and a method of designing the filters.

Since the QAM-FBMC system is greatly influenced by the spectral localization or the BER performance depending on the filter, the criterion for designing an efficient filter is important. Conventionally designed filters are inefficient in FBMC systems that do not use CP because they do not consider localization in the time domain. Complexity is high using complex coefficients and heterogeneous prototype filters. Therefore, it is necessary to design a filter suitable for multipath fading channel considering localization in time domain.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a filter and a method for designing an efficient multipath fading channel environment in a QAM-FBMC system using a simplified prototype filter in consideration of localization in a time domain.

According to an aspect of the present invention, there is provided a method of designing a filter in consideration of locality of a time domain in a filter bank-based multi-carrier system, wherein a filter applied with a frequency shift is applied to each of a plurality of sub- Each filter being matched through receive filtering, defining a total pulse shape, calculating a total interference power on a plurality of subcarriers to define a self-SIR of the QAM-FBMC transmission signal for the normalized value, The power distribution density PSD of the QAM-FBMC transmission signal is determined by a discrete time Fourier transform (DTFT), and the relationship between the filter coefficient and the fall-off rate of the DTFT of the filter is expressed as a derivative of the continuity of the filter Determining the probability and performing localization in the frequency domain through the tap and pole-off rate of the filter and determining the normalized time and the normalized energy < RTI ID = 0.0 > Used to include the step of performing a localization in time domain.

The step of defining the overall pulse shape defines a full pulse shape to satisfy GNC (generalized Nyquist criterion) to avoid Inter symbol interference (ISI) and Inter channel interference (ICI).

The step of defining the self-SIR of the QAM-FBMC transmission signal calculates a total interference power on a plurality of subcarriers, and defines a reciprocal of the calculated total interference power as a self-SIR for the normalized value.

The step of determining the relationship between the filter coefficient and the fall-off rate of the DTFT of the filter by the differentiability of the continuity of the filter comprises applying the continuity and differentiability probabilities to the continuous time function to obtain the QAM- Off rate condition with a decreasing rate of the power distribution density, and determines the relation of the poll-off rate according to the maximum integer satisfying the poll-off rate condition.

The localization in the frequency domain and the localization in the time domain perform localization in the frequency domain and localization in the time domain based on the standard deviation in the time domain of the pulse shaping filter.

In another aspect, in a filter bank-based multi-carrier system proposed in the present invention, a filter design system that takes into account the localization of a time domain applies a filter in which a frequency shift is applied to each of a plurality of sub- A pulse shape defining unit for matching each of the filters through reception filtering and defining a total pulse shape, a self-SIR of a QAM-FBMC transmission signal for a normalized value by calculating a total interference power on a plurality of subcarriers The power distribution density PSD of the QAM-FBMC transmission signal is determined by the discrete-time Fourier transform (DTFT) of the filter, and the filter coefficient and the fall-off rate ) Is determined by the possibility of differentiating the continuity of the filter, and a localization in the frequency domain is performed through the tap and the pole-off rate of the filter And a localization unit for performing localization in the time domain using the normalized time and the normalized energy.

The pulse shape defining unit defines the entire pulse shape to satisfy GNC (generalized Nyquist criterion) to avoid Inter symbol interference (ISI) and Inter channel interference (ICI).

The self-SIR defining unit calculates a total interference power on a plurality of subcarriers, and defines a reciprocal of the calculated total interference power as a self-SIR with respect to a normalized value.

Off rate determination section defines a fall-off rate condition at a decreasing rate of the power distribution density of the QAM-FBMC transmission signal by applying continuity and differentiability to the continuous time function, And determines the relationship of the pole-off rate according to the following equation.

The localization unit performs localization in the frequency domain and localization in the time domain based on the standard deviation in the time domain of the pulse shaping filter.

In another aspect, the present invention provides a QAM-FBMC system including an IFFT and FFT unit, a time domain localization filter, and an equalizer, the IFFT unit performing an IFFT on an input signal through an IFFT and FFT unit, The time domain filtering is performed through a time domain localization filter having a plurality of taps to transmit an FBMC modulated signal, an equalizer is applied to a received signal received through a multipath fading channel, And a time-domain locality-based filter: a filter applied with a frequency shift by a filter in each of a plurality of subcarriers is applied to a pulse shaping filter, each filter is matched through receive filtering, Define the shape; Calculating a total interference power on a plurality of subcarriers to define a self-SIR of the QAM-FBMC transmission signal for the normalized value; The power distribution density (PSD) of the QAM-FBMC transmission signal is determined by a discrete-time Fourier transform (DTFT) of the filter, and the relationship between the filter coefficient and the fall- ≪ / RTI > It is designed to perform localization in the frequency domain through tap and pole-off rates of the filter and perform localization in the time domain using normalized time and normalized energy.

In the time-domain locality-based filter, a self-SIR that minimizes interference is defined by setting a filter coefficient, and a condition according to a relation between a filter coefficient and a fall-off rate of a DTFT of the filter is defined as A satisfactory pole-off rate is set, and the time variance is designed such that the energy is distributed within a specified normalized time.

According to embodiments of the present invention, a filter suitable for an efficient multi-path fading channel environment in a QAM-FBMC system can be designed by considering a localization in a time domain and using a simplified prototype filter.

FIG. 1 is a diagram for explaining the structure and operation of a filter considering the localization of a time domain in a filter bank-based multi-carrier system according to an embodiment of the present invention.
2 is a diagram illustrating an overlay & sum structure according to an embodiment of the present invention.
FIG. 3 is a flowchart illustrating a method of designing a filter considering a time domain in a multi-carrier system based on a filter bank according to an embodiment of the present invention.
FIG. 4 is a diagram illustrating a configuration of a filter design system considering the localization of a time domain in a filter bank-based multi-carrier system according to an embodiment of the present invention.
5 is a graph showing the relationship between the number of filter taps and the SIR according to an exemplary embodiment of the present invention.
6 is a graph showing a relationship between SNR and BER for an AWGN channel having QPSK and 16QAM according to an embodiment of the present invention.
7 is a graph of the relationship between SNR and BER for an EPA channel with QPSK and 16QAM according to an embodiment of the present invention.
8 is a spectral localization graph according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a diagram for explaining the structure and operation of a filter considering the localization of a time domain in a filter bank-based multi-carrier system according to an embodiment of the present invention.

According to an embodiment of the present invention, a QAM-FBMC system including an IFFT and FFT performing unit, a time domain localization filter, and an equalizer performs IFFT through an IFFT and FFT performing unit of an input signal, Time domain filtering through the time domain localization filter to transmit the FBMC modulated signal. Then, the equalizer is applied to the received signal received through the multipath fading channel, and then the symbol is estimated through matching using a time domain localization filter.

Here, the time-domain locality-based filter can be designed in the following manner.

First, in the time-domain locality-based filter, a filter to which a frequency shift is applied by a filter in each of a plurality of subcarriers is applied to a pulse shaping filter, each filter is matched through reception filtering, and a whole pulse shape can be defined.

Then, a time-domain locality-based filter may define the self-SIR of the QAM-FBMC transmission signal for the normalized value by calculating the total interference power on a plurality of subcarriers.

Then, the time-domain locality-based filter determines the power distribution density (PSD) of the QAM-FBMC transmission signal by the discrete-time Fourier transform (DTFT) of the filter, off rate can be determined by the differentiability of the continuity of the filter.

In addition, the time-domain locality-based filter is designed to perform localization in the frequency domain through tap and pole-off rates of the filter and localization in the time domain using normalized time and normalized energy.

In other words, the time-domain locality-based filter according to the embodiment of the present invention sets a filter coefficient to define a self-SIR that minimizes interference, and a filter coefficient and a fall-off rate rate is set, and the time variance is designed such that the energy is distributed within a specified normalized time.

In the proposed filter bank-based multi-carrier system, a filter that takes into consideration the localness of the time domain includes an input / output unit 110, a QAM modulation unit 120, a serial / parallel conversion unit 130, an FBMC modulation unit 140, .

1A, an input bit received through an input / output unit 110 is modulated through a QAM modulator 120 and converted into parallel signals by a serial / parallel converter 130, And transmitted to the modulator 140.

The FBMC modulating unit 140 includes an IFFT and FFT performing unit 141 and a time-domain locality-based filter 142. The IFFT and FFT performing unit 141 performs M-point IFFT on the input signal, performs time domain filtering through the time domain localization based filter 142, and outputs an FBMC modulated signal of an overlap & 150).

은 프로토타입 필터

의 주파수이동이 적용된 형태로,

와 같이 나타낼 수 있다. More specifically, in a transmission signal model,

Prototype filter

In this case,

As shown in Fig.

에 대한 QAM-FBMC 시스템의 전송신호는

와 같이 나타낼 수 있다. 여기에서 M은 부반송파 개수이며,

은 펄스형성필터로 주파수 영역에서 업 샘플링(upsampling) 되어 있다.Next, the kth symbol of the mth subcarrier

The transmission signal of the QAM-FBMC system for

As shown in Fig. Where M is the number of subcarriers,

Is upsampled in the frequency domain with a pulse shaping filter.

와 같이 나타낼 수 있다.
Using a prototype filter,

As shown in Fig.

2 is a diagram illustrating an overlay & sum structure according to an embodiment of the present invention.

The transmission of the QAM-FBMC system is performed through M-point IFFT and time domain filtering. The prototype filter is a filter having N taps, and N = LM. Where L is the upsampling factor. Due to this upsampling, it is transmitted in the overlap & sum structure in the time domain.

Referring to FIG. 1B, in the signal reception operation, the signal received through the communication unit 150 is buffered and divided (buffered and sliced) and transmitted to the FBMC modulator 140. [

The FBMC modulation unit 140 includes an IFFT and FFT performing unit 141, an equalizer 143, and a time-domain locality-based filter 142. The IFFT and FFT performing unit 141 performs N-point FFT on the received signal, and applies the equalizer 143 to estimate a symbol through matching of the time-domain locality-based filter 142.

Then, it is converted into serial through the serial / parallel conversion unit 130, modulated through the QAM modulation unit 120, and outputted through the input / output unit 110.

에 대한 0번째 수신신호는

와 같다. More specifically, a multipath fading channel in a received signal model

The 0 < th >

.

Here, w denotes additive white Gaussian noise (AWGN), and the sum index - (L-1) to (L-1) has an overlap & sum structure. do. The symbol can be estimated by matching the filter after applying the equalizer to the received signal.

FIG. 3 is a flowchart illustrating a method of designing a filter considering a time domain in a multi-carrier system based on a filter bank according to an embodiment of the present invention.

In a filter bank-based multi-carrier system, a filter designing a frequency domain by a filter in each of a plurality of subcarriers is applied to a pulse shaping filter, each filter is matched through reception filtering, Defining a pulse shape; computing a total interference power on a plurality of subcarriers to define a self-SIR of a QAM-FBMC transmission signal for the normalized value, a discrete-time Fourier transform The power distribution density PSD of the QAM-FBMC transmission signal is determined by DTFT and the relationship between the filter coefficient and the fall-off rate of the DTFT of the filter is determined by the differentiability of the continuity of the filter In step 330, localization in the frequency domain is performed through the tap and the pole-off rate of the filter, and localization in the time domain is performed using the normalized time and the normalized energy (Step 340).

It is not possible to create a filter with excellent localization while preserving orthogonality by Balian-Low Theorem. Therefore, considering the trade-off relationship between orthogonality and localization, A good filter must be designed. Since all the filters are formed by the prototype filter, designing the prototype filter is to design the filter of the QAM-FBMC system, and it should be designed considering the following three conditions.

First, in step 310, the pulse shape defining unit applies a filter, in which a frequency shift is applied by a filter, to each of a plurality of subcarriers, as a pulse shaping filter. At this time, each filter is matched through reception filtering, and defines the entire pulse shape. In order to avoid Inter symbol interference (ISI) and Inter channel interference (ICI), a full pulse shape is defined to satisfy a GNC (generalized Nyquist criterion).

에 의해 주파수 이동이 적용된

필터를 펄스형성필터로 적용한다. 수신 필터링을 통해 각 필터들이 매칭되며, 전체 펄스 형태(overall pulse shape)를

와 같이 정의할 수 있다. In each subcarrier m, a prototype filter

The frequency shift is applied by

The filter is applied as a pulse shaping filter. Through inbound filtering, each filter is matched and the overall pulse shape

Can be defined as follows.

의 GNC(generalized Nyquist criterion)를 만족해야 한다. 설계하려는 필터는 발리안-로우 정리(Balian-Low Theorem)에 의해 GNC를 완벽하게 만족할 수 없고, 이것은 필터에서 간섭의 발생을 의미한다. And to avoid ISI and ICI

The GNC (generalized Nyquist criterion). The filter you are designing can not fully satisfy GNC by the Balian-Low Theorem, which means that interference is generated in the filter.

In step 320, the self-SIR definition defines the self-SIR of the QAM-FBMC transmission signal for the normalized value by calculating the total interference power on a plurality of subcarriers. At this time, a total interference power is calculated for a plurality of subcarriers, and a reciprocal of the calculated total interference power is defined as a self-SIR for the normalized value.

번째 부반송파에서 총 간섭파워를

와 같이 계산할 수 있다. 정규화된 값(

)에 대해, 위의 식의 역수를 self-SIR로 정의할 수 있다(1/interference_power). 이때, 간섭을 최소로 하는 필터를 설계하는 것이 목적이고, 다시 말해 self-SIR을 최대화하는 것이 필터 설계의 목적이다.

Lt; th > subcarrier.

Can be calculated as follows. The normalized value (

), The reciprocal of the above equation can be defined as self-SIR (1 / interference_power). At this time, it is the purpose of the filter design to minimize the interference, in other words, to maximize the self-SIR.

In step 330, the poll-off rate determining unit determines a power spectral density (PSD) of the QAM-FBMC transmission signal by a discrete-time Fourier transform (DTFT) The relationship of the fall-off rate is determined by the differentiability of the continuity of the filter. In other words, by applying the continuity and differentiability to the continuous time function, the pole-off rate condition is defined by the decreasing rate of the power distribution density of the QAM-FBMC transmission signal, and according to the maximum integer satisfying the pole- And determines the relationship of the off-rate.

에 의해 결정된다. The fall-off rate is defined as the decrease rate of the PSD of the QAM-FBMC transmission signal. At this time, it is assumed that the data signal is uncorrelated. The PSD of the QAM-FBMC transmission signal is DTFT of the prototype filter

.

와

의 폴-오프 레이트의 관계는 필터의 연속성의 미분가능성에 의해 결정된다. Prototype filter coefficients

Wow

The relationship of the pole-off rate of the filter is determined by the differentiability of the continuity of the filter.

Continuous time function representing continuity

는 아래 과정을 거쳐 관계식으로 유도할 수 있다.

Can be derived as a relational expression through the following process.

,

,

In the above equation, the pole-off rate conditions are summarized as follows by applying continuity and differentiability possibility.

Here, r is an odd integer and q is an even integer.

을 만족한다. If the maximum integer satisfying the above condition is p, then the pole-off rate is

.

In step 340, the localization unit performs localization in the frequency domain through tap and pole-off rates of the filter, and performs localization in the time domain using the normalized time and the normalized energy. And performs localization in the frequency domain and localization in the time domain based on the standard deviation in the time domain of the pulse shaping filter.

와 같은 파라미터 고려한다. 또한, 정규화된 시간과 (

) 정규화된 에너지를 (

) 이용한다. 이것은 펄스형성필터의 시간영역에서의 표준편차를 의미하며, 값이 작을수록 시간영역에서 에너지 지역화가 잘 되어 있는 것을 의미한다. CP(Cyclic Prefix)를 사용하지 않는 FBMC 시스템은

가 작을수록 다중경로 페이딩 채널에서 유효할 수 있다.
In the frequency domain, we perform localization through filter tap and pole-off rate, and perform localization in the time domain.

. Also, the normalized time and (

) Normalized energy (

). This means the standard deviation in the time domain of the pulse shaping filter, and the smaller the value, the better the energy localization in the time domain. FBMC systems that do not use CP (Cyclic Prefix)

Can be effective in a multipath fading channel.

를 설정하고, 최적화 문제(예를 들어, Pattern search algorithm 이용)를 수행한다. Designing a filter according to an embodiment of the present invention first includes the steps of:

And performs an optimization problem (for example, using a pattern search algorithm).

,

,

,

의 조건을 만족하는 것을 목표로 한다. For the optimization problem, the objective function is to minimize I _i ,

,

,

,

Is satisfied.

In other words, the pole-off rate condition is set, and the time dispersion is designed so that most of the energy is within a certain normalized time.

FIG. 4 is a diagram illustrating a configuration of a filter design system considering the localization of a time domain in a filter bank-based multi-carrier system according to an embodiment of the present invention.

The filter design system 400 according to the present embodiment may include a processor 410, a bus 420, a network interface 430, a memory 440 and a database 450. The memory 440 may include a filter design routine 442 that takes into account the operating system 441 and the temporal domain locality. The processor 410 may include a pulse shape defining unit 411, a self-SIR defining unit 412, a poll-off rate determining unit 413, and a localization unit 414. In other embodiments, the filter design system 400 may include more components than the components of FIG. However, there is no need to clearly illustrate most prior art components. For example, the filter design system 400 may include other components such as a display or a transceiver.

The memory 440 may be a computer-readable recording medium and may include a permanent mass storage device such as a random access memory (RAM), a read only memory (ROM), and a disk drive. In addition, the memory 440 may store program codes for the operating system 441 and the filter design routine 442 considering the temporal domain locality. These software components may be loaded from a computer readable recording medium separate from the memory 440 using a drive mechanism (not shown). Such a computer-readable recording medium may include a computer-readable recording medium (not shown) such as a floppy drive, a disk, a tape, a DVD / CD-ROM drive, or a memory card. In other embodiments, the software components may be loaded into the memory 440 via the network interface 430 rather than from a computer readable recording medium.

The bus 420 may enable communication and data transfer between components of the filter design system 400. The bus 420 may be configured using a high-speed serial bus, a parallel bus, a Storage Area Network (SAN), and / or any other suitable communication technology.

Network interface 430 may be a computer hardware component for coupling filter design system 400 to a computer network. The network interface 430 may connect the filter design system 400 to a computer network via a wireless or wired connection.

The database 450 may store and maintain all the information necessary for the filter design considering the localization of the time domain. And stores the extended global goods classification system as master data. Although FIG. 4 shows the construction of the database 450 in the filter design system 400, it is not limited thereto and may be omitted depending on the system implementation method or environment, It is also possible to exist as an external database built on another system of the system.

The processor 410 may be configured to process instructions of a computer program by performing basic arithmetic, logic, and input / output operations of the filter design system 400. The instructions may be provided by the memory 440 or network interface 430 and to the processor 410 via the bus 420. Processor 410 may be configured to execute program code for pulse shape defining section 411, self-SIR defining section 412, poll-off rate determining section 413, and localization section 414. [ Such program code may be stored in a recording device, such as memory 440. [

The pulse shape defining unit 411, the self-SIR defining unit 412, the poll-off rate determining unit 413 and the localizing unit 414 may be configured to perform the steps 310 to 340 of FIG. have.

The filter design system 400 may include a pulse shape defining unit 411, a self-SIR defining unit 412, a poll-off rate determining unit 413, and a localizer 414.

The pulse shape defining unit 411 applies a filter, in which a frequency shift is applied by a filter, to each of a plurality of subcarriers, as a pulse shaping filter. Then, each filter is matched through reception filtering, and the entire pulse shape is defined. The pulse shape defining unit 411 defines the entire pulse shape to satisfy the GNC (generalized Nyquist criterion) to avoid Inter symbol interference (ISI) and Inter channel interference (ICI).

The self-SIR defining section 412 defines the self-SIR of the QAM-FBMC transmission signal for the normalized value by calculating the total interference power on a plurality of subcarriers. At this time, a total interference power is calculated for a plurality of subcarriers, and a reciprocal of the calculated total interference power is defined as a self-SIR for the normalized value.

The fall-off rate determination unit 413 determines the power distribution density PSD of the QAM-FBMC transmission signal by the discrete-time Fourier transform (DTFT) of the filter, and calculates the fall- -off rate) is determined by the differentiability of the continuity of the filter. In other words, by applying the continuity and differentiability to the continuous time function, the pole-off rate condition is defined by the decreasing rate of the power distribution density of the QAM-FBMC transmission signal, and according to the maximum integer satisfying the pole- And determines the relationship of the off-rate.

The localizer 414 performs localization in the frequency domain through the tap and fall-off rates of the filter and performs localization in the time domain using the normalized time and the normalized energy. And performs localization in the frequency domain and localization in the time domain based on the standard deviation in the time domain of the pulse shaping filter.

5 is a graph showing the relationship between the number of filter taps and the SIR according to an exemplary embodiment of the present invention.

The self-SIR is measured while changing the number of filter taps, and Table 1 shows such filter coefficients.

<Table 1>

As the number of filter taps is changed and the self-SIR is measured, the value changes greatly and has the form of a step function that has a constant interval. Therefore, the filter coefficients for the smallest number of tabs 7, 11, .

Table 2 shows the comparison results of various filters.

<Table 2>

In the case of a reference filter, it is a filter designed considering only the self-SIR and the fall-off rate.

In the case of the proposed filter, it is designed to be well localized in time domain considering time dispersion.

를 작도록 설계하게 되면 대칭일 경우가 유리하므로 리얼(real) 필터가 설계되며, 복소수 부분이 없어 폴-오프 레이트 조건에도 유리하므로 더 높은 폴-오프 레이트를 만족할 수 있다.

A real filter is designed because it is advantageous in the case of symmetry, and since it has no complex part, it is also advantageous in a pole-off rate condition, so that a higher pole-off rate can be satisfied.

As described above, since the filter according to the embodiment of the present invention does not use a heterogeneous filter and only a real coefficient is used while using a homogeneous filter, the complexity is significantly reduced. The simulation results will be described with reference to Figs. 5 and 6. Fig.

6 is a graph showing a relationship between SNR and BER for an AWGN channel having QPSK and 16QAM according to an embodiment of the present invention.

7 is a graph of the relationship between SNR and BER for an EPA channel with QPSK and 16QAM according to an embodiment of the present invention.

To implement QAM-FBMC system, filter case 2, C is used, subcarrier M = 64, upsampling factor L = 4 and QPSK modulation (M = 512 for spectrum localization simulation) are used. Simulations are also performed using SISO channels and ZF (zero-forcing) equalizers.

<Table 3>

<Table 4>

가 작기 때문에 보다 성능이 우수한 것을 확인 할 수 있다.
As shown in FIG. 6 and FIG. 7, although the performance is deteriorated in the AWGN due to the low SIR, even though the SIR is low when the actual channel is experienced

It is possible to confirm that the performance is better.

8 is a spectral localization graph according to an embodiment of the present invention.

It is confirmed that the proposed filter has excellent performance by designing the pole-off rate even with the filter using the same number of taps.

Thus, considering the localization in the time domain, a simplified prototype filter can be used to design a filter suitable for an efficient multi-path fading channel environment in a QAM-FBMC system.

The apparatus described above may be implemented as a hardware component, a software component, and / or a combination of hardware components and software components. For example, the apparatus and components described in the embodiments may be implemented within a computer system, such as, for example, a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable array (FPA) A programmable logic unit (PLU), a microprocessor, or any other device capable of executing and responding to instructions. The processing device may execute an operating system (OS) and one or more software applications running on the operating system. The processing device may also access, store, manipulate, process, and generate data in response to execution of the software. For ease of understanding, the processing apparatus may be described as being used singly, but those skilled in the art will recognize that the processing apparatus may have a plurality of processing elements and / As shown in FIG. For example, the processing unit may comprise a plurality of processors or one processor and one controller. Other processing configurations are also possible, such as a parallel processor.

The software may include a computer program, code, instructions, or a combination of one or more of the foregoing, and may be configured to configure the processing device to operate as desired or to process it collectively or collectively Device can be commanded. The software and / or data may be in the form of any type of machine, component, physical device, virtual equipment, computer storage media, or device As shown in FIG. The software may be distributed over a networked computer system and stored or executed in a distributed manner. The software and data may be stored on one or more computer readable recording media.

The method according to an embodiment may be implemented in the form of a program command that can be executed through various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions to be recorded on the medium may be those specially designed and configured for the embodiments or may be available to those skilled in the art of computer software. Examples of computer-readable media include magnetic media such as hard disks, floppy disks and magnetic tape; optical media such as CD-ROMs and DVDs; magnetic media such as floppy disks; Magneto-optical media, and hardware devices specifically configured to store and execute program instructions such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine language code such as those produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. For example, it is to be understood that the techniques described may be performed in a different order than the described methods, and / or that components of the described systems, structures, devices, circuits, Lt; / RTI &gt; or equivalent, even if it is replaced or replaced.

Therefore, other implementations, other embodiments, and equivalents to the claims are also within the scope of the following claims.

Claims (12)

Applying transmit filtering by a pulse shaping filter at each of a plurality of subcarriers, defining each of the filters through receive filtering, and defining an entire pulse filter;
Calculating a total interference power on a plurality of subcarriers to define a self-SIR of the QAM-FBMC transmission signal for the normalized value;
The power distribution density (PSD) of the QAM-FBMC transmission signal is determined by a discrete-time Fourier transform (DTFT) of the filter, and the relationship between the filter coefficient and the fall- By the differential likelihood of the input signal; And
The localization in the frequency domain of the QAM-FBMC transmission signal is performed through the number of frequency domain filter coefficients and the fall-off rate, and the energy distribution in the normalized time domain is used to estimate the QAM- &Lt; RTI ID = 0.0 &gt;
And a time domain localization filter. The method according to claim 1,
Wherein defining the full pulse filter comprises:
In order to avoid Inter symbol interference (ISI) and Inter channel interference (ICI), the entire pulse shape is defined to satisfy a GNC (generalized Nyquist criterion)
A Design Method of Locality based Filter in Time Domain. The method according to claim 1,
The step of defining the self-SIR of the QAM-FBMC transmission signal includes:
Calculating a total interference power on a plurality of subcarriers, and defining a reciprocal of the calculated total interference power as a self-SIR for the normalized value
A Design Method of Locality based Filter in Time Domain. The method according to claim 1,
Wherein the step of determining the relationship between the filter coefficient and the fall-off rate of the DTFT of the filter by the differentiability of the continuity of the filter comprises:
Off rate condition with a decreasing rate of the power distribution density of the QAM-FBMC transmission signal by applying continuity and differentiability probabilities to the continuous time function, and calculates a fall-off rate according to the maximum integer satisfying the fall- To determine the relationship
A Design Method of Locality based Filter in Time Domain. The method according to claim 1,
Wherein the step of performing the localization in the frequency domain and the step of performing the localization in the time domain include:
Localization in the frequency domain and localization in the time domain based on the standard deviation in the time domain of the pulse shaping filter
A Design Method of Locality based Filter in Time Domain. A pulse shape defining unit applying transmission filtering by a pulse shaping filter in each of a plurality of subcarriers, matching each filter through reception filtering, and defining an entire pulse filter;
A self-SIR defining unit for calculating a total interference power on a plurality of subcarriers to define a self-SIR of a QAM-FBMC transmission signal with respect to a normalized value;
The power distribution density (PSD) of the QAM-FBMC transmission signal is determined by a discrete-time Fourier transform (DTFT) of the filter, and the relationship between the filter coefficient and the fall- A pole-off rate determination unit that determines a pole-off rate according to the differentiability of the output signal; And
Localization of the QAM-FBMC transmission signal in the frequency domain through the number of frequency domain filter coefficients and the pole-off rate and localization in the time domain of the QAM-FBMC transmission signal using the energy distribution in the normalized time domain Localization department performing
Time domain localization filter design system. The method according to claim 6,
Wherein the pulse shape defining unit comprises:
In order to avoid Inter symbol interference (ISI) and Inter channel interference (ICI), the entire pulse shape is defined to satisfy a GNC (generalized Nyquist criterion)
Time Domain Region Based Filter Design System. The method according to claim 6,
The self-SIR defining unit includes:
Calculating a total interference power on a plurality of subcarriers, and defining a reciprocal of the calculated total interference power as a self-SIR for the normalized value
Time Domain Region Based Filter Design System. The method according to claim 6,
Wherein the poll-off rate determination unit comprises:
Off rate condition with a decreasing rate of the power distribution density of the QAM-FBMC transmission signal by applying continuity and differentiability probabilities to the continuous time function, and calculates a fall-off rate according to the maximum integer satisfying the fall- To determine the relationship
Time Domain Region Based Filter Design System. The method according to claim 6,
The localization unit,
Localization in the frequency domain and localization in the time domain based on the standard deviation in the time domain of the pulse shaping filter
Time Domain Region Based Filter Design System. In a QAM-FBMC system including an IFFT and FFT implementation, a time domain localization filter, and an equalizer,
An input signal is subjected to IFFT through an IFFT and FFT performing unit, time domain filtering is performed through a time domain localization filter having a plurality of taps to transmit an FBMC modulated signal, After the equalizer is applied to the signal, the symbol is estimated through matching by the region-based filter in the time domain,
The time-domain locality-based filter is:
Applying transmit filtering by a pulse shaping filter at each of a plurality of subcarriers, matching each of the filters through receive filtering, defining an entire pulse filter;
Calculating a total interference power on a plurality of subcarriers to define a self-SIR of the QAM-FBMC transmission signal for the normalized value;
The power distribution density (PSD) of the QAM-FBMC transmission signal is determined by a discrete-time Fourier transform (DTFT) of the filter, and the relationship between the filter coefficient and the fall- &Lt; / RTI &gt;
Localization of the QAM-FBMC transmission signal in the frequency domain through the number of frequency domain filter coefficients and the pole-off rate and localization in the time domain of the QAM-FBMC transmission signal using the energy distribution in the normalized time domain Designed to perform
QAM-FBMC system. 12. The method of claim 11,
Wherein the time-domain locality-
By setting filter coefficients, a self-SIR that minimizes interference is defined, and a poll-off rate that satisfies the condition according to the relationship between the filter coefficient and the fall-off rate of the DTFT of the filter is set , The time variance is designed so that the energy is distributed within a specified normalized time
QAM-FBMC system.

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