WO2021136101A1

WO2021136101A1 - Filter coefficient determining method and apparatus and digital das system

Info

Publication number: WO2021136101A1
Application number: PCT/CN2020/139532
Authority: WO
Inventors: 吕辉; 张文; 樊奇彦; 李杨君
Original assignee: 京信网络***股份有限公司
Priority date: 2019-12-31
Filing date: 2020-12-25
Publication date: 2021-07-08
Also published as: CN111211759A; CN111211759B

Abstract

A filter coefficient determining method and apparatus and a digital DAS system. The filter coefficient determining method comprises: obtaining a first filter parameter of a target filter supported by a target communication system (S11); adjusting multiple sub-filters on the basis of the first filter parameter, and when it is determined that a same filtering effect as the target filter is achieved, obtaining sub-filter parameters corresponding to the sub-filters (S12); determining coefficients of the sub-filters according to the sub-filter parameters (S13). Thus, an existing mobile communication network is upgraded to a new generation of mobile communication network without changing original device resources of a deployed target communication system, thereby improving the spectrum efficiency and communication rate.

Description

滤波器系数确定方法、装置和数字DAS***Method and device for determining filter coefficient and digital DAS system

本公开要求于2019年12月31日提交中国专利局、申请号为CN201911417046.2、发明名称为“滤波器系数确定方法、装置和数字DAS***”的中国专利申请的优先权，其全部内容通过引用结合在本公开中。This disclosure claims the priority of a Chinese patent application filed with the Chinese Patent Office, the application number is CN201911417046.2, and the invention title is "filter coefficient determination method, device and digital DAS system" on December 31, 2019, and the entire content of it is passed Reference is incorporated in this disclosure.

技术领域Technical field

本公开涉及通信技术领域，尤其涉及一种滤波器系数确定方法、装置和数字DAS***。The present disclosure relates to the field of communication technology, and in particular to a method and device for determining filter coefficients and a digital DAS system.

背景技术Background technique

在现有频谱资源有限的情况下，提高频谱利用率成为移动通信***中迫切需要解决的技术问题，而新一代移动通信技术往往具有更高的频谱利用率，因此成为了业界高度关注和研究的重要课题。In the case of limited existing spectrum resources, improving spectrum utilization has become an urgent technical problem in mobile communication systems. The new generation of mobile communication technologies often have higher spectrum utilization, so it has become a topic of great concern and research in the industry. important topic.

因新一代移动通信技术的频谱利用率明显高于原移动通信技术的频谱利用率，在面向新一代移动通信技术的应用中，数字DAS***(Distributed Antenna System，分布式天线***)从现有的移动通信网络升级支持新一代移动通信网络时，某些运营商期望从原移动通信网络带宽升级支持到新一代移动通信网络的带宽，如从LTE(Long Term Evolution,长期演进技术)5/10/15/20M升级支持到NR5/10/15/20M带宽。Because the spectrum utilization rate of the new generation mobile communication technology is significantly higher than that of the original mobile communication technology, in the application of the new generation mobile communication technology, the digital DAS system (Distributed Antenna System, distributed antenna system) changes from the existing When the mobile communication network is upgraded to support the new generation of mobile communication networks, some operators expect to upgrade the bandwidth of the original mobile communication network to support the bandwidth of the new generation of mobile communication networks, such as from LTE (Long Term Evolution, long-term evolution technology) 5/10/ 15/20M upgrade supports to NR5/10/15/20M bandwidth.

如果需要从原有DAS***升级支持新一代移动通信网络，需要选择更大的芯片，如FPGA芯片(Field-Programmable Gate Array，现场可编程门阵列)，但由于原***的芯片资源规模都已经选定。因此，在已部署的数字DAS***中，无法在设备不改动原器件资源的情形下，将现有移动通信网络升级到新一代移动通信网络，以提高频谱利用率和通信速率。If you need to upgrade from the original DAS system to support the new generation of mobile communication networks, you need to choose a larger chip, such as FPGA chip (Field-Programmable Gate Array), but because the chip resource scale of the original system has been selected set. Therefore, in the deployed digital DAS system, it is impossible to upgrade the existing mobile communication network to a new generation mobile communication network without changing the original device resources in order to improve the spectrum utilization rate and the communication rate.

发明内容Summary of the invention

(一)要解决的技术问题(1) Technical problems to be solved

本公开要解决的技术问题是解决现有的在已部署的数字DAS***中，无法在设备不改动原器件资源的情形下，将现有移动通信网络升级到新一代移动通信网络，以提高频谱利用率和通信速率的问题。The technical problem to be solved by the present disclosure is to solve the existing deployed digital DAS system, it is impossible to upgrade the existing mobile communication network to a new generation mobile communication network without changing the original device resources, so as to increase the frequency spectrum. The problem of utilization and communication speed.

(二)技术方案(2) Technical solution

为了解决上述技术问题，本公开实施例提供了一种滤波器系数确定方法、装置和数字DAS***。In order to solve the above technical problems, embodiments of the present disclosure provide a method and device for determining filter coefficients, and a digital DAS system.

第一方面，本公开实施例提供一种滤波器系数确定方法，包括如下步骤：In the first aspect, embodiments of the present disclosure provide a method for determining filter coefficients, which includes the following steps:

获取目标通信***所支持的目标滤波器的第一滤波参数；Acquiring the first filter parameter of the target filter supported by the target communication system;

基于所述第一滤波参数对多个子滤波器进行调试，确定达到与所述目标滤波器相同的滤波效果时，得到各个子滤波器所对应的子滤波参数；Debug multiple sub-filters based on the first filter parameter, and obtain the sub-filter parameters corresponding to each sub-filter when it is determined that the same filtering effect as the target filter is achieved;

根据所述子滤波参数确定各子滤波器的系数。The coefficients of each sub-filter are determined according to the sub-filter parameters.

第二方面，本公开实施例还提供了一种滤波器系数确定装置，包括：In the second aspect, an embodiment of the present disclosure also provides a filter coefficient determination device, including:

获取模块，配置为获取目标通信***所支持的目标滤波器的第一滤波参数；An obtaining module, configured to obtain the first filter parameter of the target filter supported by the target communication system;

调试模块，配置为基于所述第一滤波参数对多个子滤波器进行调试，确定达到与所述目标滤波器相同的滤波效果时，得到各个子滤波器所对应的子滤波参数；A debugging module, configured to debug multiple sub-filters based on the first filter parameter, and obtain the sub-filter parameters corresponding to each sub-filter when it is determined that the same filtering effect as the target filter is achieved;

确定模块，配置为根据所述子滤波参数确定各子滤波器的系数。The determining module is configured to determine the coefficients of each sub-filter according to the sub-filter parameters.

第三方面，本公开实施例还提供了一种数字DAS***，包括接入单元、扩展单元和远端单元，所述接入单元、扩展单元和远端单元中的至少一个滤波器系数采用如上任一项所述的滤波器系数确定方法进行确定。In a third aspect, the embodiments of the present disclosure also provide a digital DAS system, including an access unit, an extension unit, and a remote unit. At least one filter coefficient of the access unit, the extension unit, and the remote unit is as follows: The method for determining filter coefficients described in any of the preceding items is used for determining.

第四方面，本公开实施例还提供了一种计算机存储介质，其中，该计算机存储介质可存储有程序，该程序执行时可实现本公开第一方面提供的滤波器系数确定方法的各实现方式中的部分或全部步骤。In a fourth aspect, the embodiments of the present disclosure also provide a computer storage medium, wherein the computer storage medium may store a program, and when the program is executed, each implementation manner of the filter coefficient determination method provided in the first aspect of the present disclosure can be implemented Some or all of the steps in.

(三)有益效果(3) Beneficial effects

本公开实施例提供的上述技术方案与现有技术相比具有如下优点：Compared with the prior art, the above-mentioned technical solutions provided by the embodiments of the present disclosure have the following advantages:

1.本公开提供的滤波器系数确定方法，通过获取目标通信***所支持的目标滤波器的第一滤波参数，基于第一滤波参数对多个子滤波器进行调试，确定达到与所述目标滤波器相同的滤波效果时，得到各个子滤波器所对应的子滤波参数，并根据所述子滤波参数确定各子滤波器的系数，以后续利用各子滤波器的系数，在原FPGA芯片上实现信号的乘积累加，以达到滤波的目的，使多个子滤波器总的合成响应与目标滤波器的滤波响应相同，从而实现将多个子滤波器替换目标滤波器，并达到相同的滤波效果，从而在已部署的目标通信***不增加FPGA逻辑资源的数量的情形下，可使用原FPGA器件，实现将现有移动通信网络升级到新一代移动通信网络，以提高频谱利用率和通信速率。1. The method for determining filter coefficients provided by the present disclosure obtains the first filter parameter of the target filter supported by the target communication system, and debugs a plurality of sub-filters based on the first filter parameter, and determines that the filter coefficient reaches the target filter. When the same filtering effect is obtained, the sub-filter parameters corresponding to each sub-filter are obtained, and the coefficients of each sub-filter are determined according to the sub-filter parameters, so as to subsequently use the coefficients of each sub-filter to realize signal processing on the original FPGA chip. Multiply and accumulate to achieve the purpose of filtering, so that the total composite response of multiple sub-filters is the same as the filter response of the target filter, so as to replace multiple sub-filters with the target filter and achieve the same filtering effect. Without increasing the number of FPGA logic resources in the target communication system, the original FPGA device can be used to upgrade the existing mobile communication network to a new-generation mobile communication network to improve spectrum utilization and communication speed.

2.本公开提供的滤波器系数确定方法，根据子滤波器每次调试得到的子滤波调试参数计算各子滤波器的调试系数，当各个子滤波器的调试系数长度之和最小时，将各个子滤波器当前调试得到的子滤波调试参数作为各个子滤波器所对应的子滤波参数，从而得到器件资源最优的子滤波器系数所对应的子滤波参数。2. The method for determining filter coefficients provided by the present disclosure calculates the tuning coefficients of each sub-filter according to the sub-filter tuning parameters obtained during each tuning of the sub-filter. When the sum of the lengths of the tuning coefficients of each sub-filter is the smallest, each The sub-filter tuning parameters currently obtained by the sub-filter are used as the sub-filter parameters corresponding to each sub-filter, so as to obtain the sub-filter parameters corresponding to the sub-filter coefficients with the optimal device resources.

3.本公开提供的滤波器系数确定方法，当目标通信***传输的采样率不变，且总带宽发生变化时，重新调试得到各子滤波器的系数，将各子滤波器重新调试得到的系数与原带宽对应的系数进行系数长度比较，选取系数长度较长的系数作为总带宽变化后的子滤波器的系数，以重新得到由各子滤波器系数组成的系数组，从而为了兼容滤波器系数较短时，计算较长的滤波器系数长度与较短的子滤波器系数长度的差值，将差值的一半分别添加在较短滤波器系数的起始和结束处，从而使不同长度的滤波器系数长度保持一致，实现动态调整子滤波器的系数，不需要每次带宽变化时重新加载FPGA Bit文件，显著减少开发工作量。3. In the method for determining filter coefficients provided by the present disclosure, when the sampling rate transmitted by the target communication system is unchanged and the total bandwidth changes, the coefficients of each sub-filter are re-tuned, and the coefficients obtained by re-tuning each sub-filter The coefficient length is compared with the coefficient corresponding to the original bandwidth, and the coefficient with the longer coefficient length is selected as the coefficient of the sub-filter after the total bandwidth is changed, so as to retrieve the coefficient group composed of the coefficients of the sub-filters, so as to be compatible with the filter coefficients. When it is shorter, calculate the difference between the longer filter coefficient length and the shorter sub-filter coefficient length, and add half of the difference to the start and end of the shorter filter coefficient, so that The length of the filter coefficients is kept the same, which realizes the dynamic adjustment of the coefficients of the sub-filters, and does not need to reload the FPGA Bit file every time the bandwidth changes, which significantly reduces the development workload.

4.本公开根据目标通信***的资源剩余情况，将目标通信***的目标滤波器替换为多个子滤波器；其中，所述子滤波器为基于FRM的可变带宽成型滤波器，从而将实现成本较高的目标滤波器替换为实现成本较低的子滤波器组，以节约成本。4. The present disclosure replaces the target filter of the target communication system with a plurality of sub-filters according to the remaining resources of the target communication system; wherein, the sub-filters are FRM-based variable bandwidth shaping filters, thereby reducing the cost The higher target filter is replaced with a sub-filter bank with lower implementation cost to save cost.

5.本公开提供的一种数字DAS***，采用本公开提供的滤波器系数确定方法确定的滤波器可灵活放置在接入单元、扩展单元或远端单元中，以在已部署的目标通信***不改动原器件资源的情形下，实现将现有移动通信网络升级到新一代移动通信网络，以提高频谱利用率和通信速率，并显著提高数字DAS***的使用年限和利用率。5. A digital DAS system provided by the present disclosure. The filter determined by the method for determining filter coefficients provided by the present disclosure can be flexibly placed in the access unit, expansion unit or remote unit to be used in the deployed target communication system. Without changing the original device resources, the existing mobile communication network can be upgraded to a new generation mobile communication network to improve the spectrum utilization and communication speed, and significantly improve the service life and utilization of the digital DAS system.

附图说明Description of the drawings

图1为本公开一个实施例中提供的滤波器系数确定方法的实施环境图；Fig. 1 is an implementation environment diagram of a method for determining filter coefficients provided in an embodiment of the present disclosure;

图2为本公开一个实施例中提供的滤波器系数确定方法的实施环境图；FIG. 2 is an implementation environment diagram of a method for determining filter coefficients provided in an embodiment of the present disclosure;

图3为本公开提供的滤波器系数确定方法一种实施例的流程图；FIG. 3 is a flowchart of an embodiment of a method for determining filter coefficients provided by the present disclosure;

图4为数字DAS***中的一种下行链路处理框图；Figure 4 is a block diagram of a downlink processing in a digital DAS system;

图5为基于常规方法设计的目标滤波器的整体响应示意图；Figure 5 is a schematic diagram of the overall response of a target filter designed based on a conventional method;

图6为基于FRM技术的一种下行处理链路处理框图；Figure 6 is a processing block diagram of a downlink processing link based on FRM technology;

图7为一种FRM滤波器结构图；Figure 7 is a structural diagram of an FRM filter;

图8a和8b分别为原型成型滤波器及内插6倍后的频率响应图；Figures 8a and 8b are the frequency response diagrams of the prototype shaping filter and the 6-fold interpolation respectively;

图9为屏蔽滤波器Hma(Z)的一种频率响应图；Figure 9 is a frequency response diagram of the shielding filter Hma(Z);

图10为屏蔽滤波器Hmc(Z)的一种频率响应图；Figure 10 is a frequency response diagram of the shielding filter Hmc(Z);

图11为基于FRM技术的多个子滤波器的总响应图；Figure 11 is a total response diagram of multiple sub-filters based on FRM technology;

图12为一种FIR滤波器的参数配置图；Figure 12 is a parameter configuration diagram of a FIR filter;

图13为本公开提供的滤波器系数确定装置的结构框图；FIG. 13 is a structural block diagram of a device for determining filter coefficients provided by the present disclosure;

图14为本公开提供的滤波器系数确定装置一种实施例的模块框图。FIG. 14 is a block diagram of a module of an embodiment of a device for determining filter coefficients provided by the present disclosure.

具体实施方式Detailed ways

图1为一个实施例中提供的滤波器系数确定方法的实施环境图，在图1中，出示了一种典型的数字DAS***，该数字DAS***包括基站、数字近端接入单元和远端数字射频拉远单元。其中，数字近端接入单元包括射频下变频、A/D转换单元、数字下变频单元、基带数据压缩单元及发射器，在下行链路中，分别把接收到的射频信号进行射频下变频、进行AD采样数字化处理、然后进行数字下变频，并经过基带数据压缩后通过FPGA芯片内嵌的发射器发送到光纤链路上，通过光纤拉远，在远端数字射频拉远单元中对接收到的基带信号进行处理。所述远端数字射频拉远单元包括接收器、基带数据解压缩单元、数字上变频单元、D/A转换单元及射频上变频及放大单元，以对接收到的基带信号解压缩、数字上变频、经数模转换，并通过射频上变频及放大后经过天线发射到空中。上行链路是下行链路的逆过程，在此不再具体赘述。Figure 1 is an implementation environment diagram of the filter coefficient determination method provided in an embodiment. In Figure 1, a typical digital DAS system is shown. The digital DAS system includes a base station, a digital near-end access unit, and a remote Digital radio remote unit. Among them, the digital near-end access unit includes radio frequency down-conversion, A/D conversion unit, digital down-conversion unit, baseband data compression unit and transmitter. In the downlink, the received radio frequency signal is respectively subjected to radio frequency down-conversion, Carry out AD sampling and digital processing, and then digital down-conversion, and after baseband data compression, it is sent to the optical fiber link through the transmitter embedded in the FPGA chip, and it is pulled out through the optical fiber, and the received signal is received in the remote digital radio frequency remote unit. The baseband signal is processed. The remote digital radio frequency remote unit includes a receiver, a baseband data decompression unit, a digital up-conversion unit, a D/A conversion unit, and a radio frequency up-conversion and amplification unit to decompress and digitally up-convert the received baseband signal , After digital-to-analog conversion, and through radio frequency up-conversion and amplification, it is transmitted into the air through the antenna. The uplink is the reverse process of the downlink, and will not be described in detail here.

图2为另一个实施例中提供的滤波器系数确定方法的实施环境图，出示了另一种数字DAS***，其除包括数字近端接入单元和远端数字射频拉远单元之外，还包括数字扩展单元，即数字近端接入单元先链接到数字扩展单元，通过数字扩展单元链接到远端数字射频拉远单元。Figure 2 is an implementation environment diagram of the method for determining filter coefficients provided in another embodiment, showing another digital DAS system, which includes a digital near-end access unit and a remote digital radio remote unit, and also Including the digital extension unit, that is, the digital near-end access unit is first linked to the digital extension unit, and the digital extension unit is linked to the remote digital radio remote unit.

请参阅图3，本公开提供一种滤波器系数确定方法，以在不改动原器件资源的情况下，实现将当前通信***升级至新一代移动通信***。在一实施例中，滤波器系数确定方法包括如下步骤：Referring to FIG. 3, the present disclosure provides a method for determining filter coefficients, so as to upgrade the current communication system to a new generation mobile communication system without changing the original device resources. In an embodiment, the method for determining filter coefficients includes the following steps:

S11、获取目标通信***所支持的目标滤波器的第一滤波参数；S11. Acquire the first filter parameter of the target filter supported by the target communication system;

本实施例分析目标通信***的目标滤波器的第一滤波参数，所述第一滤波参数可包括目标滤波器的通带截止频率fpass、阻带起始频率fstop、采样率fs、阻带抑制及通带纹波，并计算目标通信***总滤波器的通带截止频率wpass＝fpass/fs，阻带起始频率ws＝fstop/fs。This embodiment analyzes the first filter parameter of the target filter of the target communication system, and the first filter parameter may include the passband cut-off frequency fpass of the target filter, the stopband start frequency fstop, the sampling rate fs, the stopband suppression, and Pass-band ripple, and calculate the pass-band cut-off frequency wpass=fpass/fs of the total filter of the target communication system, and the stop-band start frequency ws=fstop/fs.

例如，当目标通信***为第五代移动通信***时，数字DAS***需要考虑到从现有4G LTE网络升级支持5G NR，此时，需要分析5G NR所支持的目标滤波器的通带截止频率fpass、阻带起始频率fstop、采样率fs，阻带抑制以及通带纹波。For example, when the target communication system is a fifth-generation mobile communication system, the digital DAS system needs to consider upgrading from the existing 4G LTE network to support 5G NR. At this time, it is necessary to analyze the passband cutoff frequency of the target filter supported by 5G NR. fpass, stopband start frequency fstop, sampling rate fs, stopband rejection and passband ripple.

在一实施例中，在步骤S11中，获取目标通信***所支持的目标滤波器的第一滤波参数之前，还可包括：In an embodiment, in step S11, before acquiring the first filter parameter of the target filter supported by the target communication system, the method may further include:

根据目标通信***的资源剩余情况，将目标通信***的所述目标滤波器替换为多个子滤波器；其中，所述子滤波器为基于FRM的可变带宽成型滤波器。According to the remaining resources of the target communication system, the target filter of the target communication system is replaced with a plurality of sub-filters; wherein, the sub-filters are FRM-based variable bandwidth shaping filters.

由于5G NR频谱利用率高，NR20M信号通带宽度达19.08MHz，而在4G LTE20MHz中，信号通带宽度仅为18MHz。在宽带数字DAS***中，NR100MHz带宽，信号带宽为98.28MHz，频谱利用率为98.28％。如果是纯5G NR***中，重新设计近端和远端信号链，可以考虑选择面积较大的FPGA芯片。但是原有4G数字DAS***要升级支持5G NR，由于原有FPGA器件资源规模都已经选定，在设备不改动硬件(FPGA资源不变)的情形下，无法从现有4G LTE升级到5G NR。为了实现支持5G NR高频谱利用率的设备，本实施例需根据已有数字DAS***的数字近端接入单元、扩展单元、远端数字射频拉远单元的资源剩余情况，将原可能位于数字近端接入单元、扩展单元、远端数字射频拉远单元中的4G LTE可变带宽成型滤波器，替换为基于FRM(Frequency Response Masking，频率响应屏蔽)的可变带宽成型滤波器。其中，所述资源包括逻辑资源、寄存器资源、查找表资源、乘法器及加法器等资源。Due to the high utilization rate of the 5G NR spectrum, the NR20M signal passband width is 19.08MHz, while in 4G LTE20MHz, the signal passband width is only 18MHz. In the wideband digital DAS system, the NR100MHz bandwidth, the signal bandwidth is 98.28MHz, and the spectrum utilization rate is 98.28%. If it is a pure 5G NR system, to redesign the near-end and far-end signal chains, consider choosing a larger FPGA chip. However, the original 4G digital DAS system needs to be upgraded to support 5G NR. Since the original FPGA device resource scale has been selected, it is impossible to upgrade from the existing 4G LTE to 5G NR without changing the hardware of the equipment (FPGA resources remain unchanged) . In order to realize a device that supports 5G NR high spectrum utilization, this embodiment needs to change the original digital radio access unit, extension unit, and remote digital radio remote unit's remaining resources based on the existing digital DAS system. The 4G LTE variable bandwidth shaping filter in the near-end access unit, extension unit, and remote digital radio remote unit is replaced with a variable bandwidth shaping filter based on FRM (Frequency Response Masking). Wherein, the resources include logic resources, register resources, look-up table resources, multipliers, adders and other resources.

本实施例根据目标通信***的资源剩余情况，将目标通信***的目标滤波器替换为多个基于FRM的可变带宽成型滤波器，从而将实现成本较高的目标滤波器替换为实现成本较低的子滤波器，以节约成本。In this embodiment, according to the remaining resources of the target communication system, the target filter of the target communication system is replaced with multiple FRM-based variable bandwidth shaping filters, thereby replacing the target filter with a higher implementation cost with a lower implementation cost The sub-filter to save cost.

S12、基于所述第一滤波参数对多个子滤波器进行调试，确定达到与所述目标滤波器相同的滤波效果时，得到各个子滤波器所对应的子滤波参数；S12: Debug multiple sub-filters based on the first filter parameter, and obtain the sub-filter parameters corresponding to each sub-filter when it is determined that the same filtering effect as the target filter is achieved;

本步骤根据获取的第一滤波参数对多个子滤波器进行调试仿真，并根据调试结果，判断多个子滤波器的总体响应是否与目标滤波器的响应相同或相近，若是，则获取当前调试各个子滤波器所对应的子滤波参数。所述子滤波参数至少包括子滤波器的通带截止频率和阻带起始频率。In this step, the multiple sub-filters are debugged and simulated according to the obtained first filter parameters, and based on the debugging results, it is determined whether the overall response of the multiple sub-filters is the same or similar to the response of the target filter. If so, the current debugged sub-filters are obtained. The sub-filter parameter corresponding to the filter. The sub-filter parameters include at least the pass-band cut-off frequency and stop-band start frequency of the sub-filter.

S13、根据所述子滤波参数确定各子滤波器的系数。S13. Determine the coefficient of each sub-filter according to the sub-filtering parameter.

本步骤根据所述子滤波参数确定各子滤波器的系数。在一实施例中，计算各子滤波器的系数时，可根据所述子滤波参数设定各子滤波器的通带纹波和阻带衰减，根据所述通带纹波和阻带衰减，利用firpmord函数计算各子滤波器的系数。当然，还可通过其他计算方式计算各子滤波器的系数，在此不做限定。In this step, the coefficients of each sub-filter are determined according to the sub-filter parameters. In an embodiment, when calculating the coefficients of each sub-filter, the pass-band ripple and stop-band attenuation of each sub-filter can be set according to the sub-filter parameters, and according to the pass-band ripple and stop-band attenuation, Use the firpmord function to calculate the coefficients of each sub-filter. Of course, the coefficients of each sub-filter can also be calculated by other calculation methods, which are not limited here.

本公开提供的滤波器系数确定方法，通过获取目标通信***所支持的目标滤波器的第一滤波参数，基于第一滤波参数对多个子滤波器进行调试，确定达到与所述目标滤波器相同的滤波效果时，得到各个子滤波器所对应的子滤波参数，并根据所述子滤波参数确定各子滤波器的系数，以后续利用各子滤波器的系数，在原FPGA芯片上实现信号的乘积累加，以达到滤波的目的，使多个子滤波器总的合成响应与目标滤波器的滤波响应相同，从而实现将多个子滤波器替换目标滤波器，并达到相同的滤波效果，从而在已部署的目标通信***不增加FPGA逻辑资源的数量的情形下，可使用原FPGA器件，实现将现有移动通信网络升级到新一代移动通信网络，以提高频谱利用率和通信速率。The method for determining filter coefficients provided by the present disclosure obtains the first filter parameter of the target filter supported by the target communication system, and debugs a plurality of sub-filters based on the first filter parameter to determine that the filter coefficient is the same as the target filter. During the filtering effect, the sub-filter parameters corresponding to each sub-filter are obtained, and the coefficients of each sub-filter are determined according to the sub-filter parameters, and the coefficients of each sub-filter are subsequently used to realize signal multiplication and accumulation on the original FPGA chip. In order to achieve the purpose of filtering, the total composite response of multiple sub-filters is the same as the filter response of the target filter, so that multiple sub-filters can replace the target filter and achieve the same filtering effect. Under the condition that the communication system does not increase the number of FPGA logic resources, the original FPGA device can be used to upgrade the existing mobile communication network to a new generation mobile communication network, so as to improve the spectrum utilization rate and communication rate.

在一实施例中，所述滤波器系数确定方法还可包括：In an embodiment, the method for determining filter coefficients may further include:

当目标通信***传输的采样率不变，且总带宽发生变化时，重新调试得到各子滤波器的系数；When the sampling rate transmitted by the target communication system does not change, and the total bandwidth changes, re-adjust to obtain the coefficients of each sub-filter;

将各子滤波器重新调试得到的系数与原带宽对应的系数进行系数长度比较，选取系数长度长的系数作为总带宽变化后的子滤波器的系数，并得到由各子滤波器系数组成的系数组。Compare the coefficient length of the coefficients obtained from the re-adjustment of each sub-filter with the coefficients corresponding to the original bandwidth, select the coefficient with the longer coefficient length as the coefficient of the sub-filter after the total bandwidth change, and obtain the coefficients composed of the coefficients of the sub-filters group.

当目标***传输的采样率固定不变时，数字DAS***总的带宽发生变化时，如传输采样率仍为76.8Msps，目标***传输的带宽由NR60MHz变为NR50MHz，需要重新设计各个子滤波器的系数，如选取较长子滤波器系数长度的值作为该子滤波器系数的长度，计算较长的滤波器系数长度与较短的子滤波器系数长度的差值，将差值的一半分别添加在较短滤波器系数的起始和结束处，从而使不同长度的滤波器系数长度一样，以兼容数字DAS***采样率不变而带宽变化需要设置不同的子滤波器系数。为了使设计更加简化，可以在设计时使各个子滤波器的系数长度固定，系数值可配置更新，时延模块Z-M(N-1)/2也可以动态调整，不需要每次带宽变化重新加载FPGA Bit文件。When the sampling rate of the target system transmission is fixed, and the total bandwidth of the digital DAS system changes, for example, the transmission sampling rate is still 76.8Msps, and the transmission bandwidth of the target system is changed from NR60MHz to NR50MHz. It is necessary to redesign each sub-filter. Coefficient. If the value of the longer sub-filter coefficient length is selected as the length of the sub-filter coefficient, the difference between the longer filter coefficient length and the shorter sub-filter coefficient length is calculated, and half of the difference is added to The start and end of the shorter filter coefficients, so that the filter coefficients of different lengths have the same length, to be compatible with the digital DAS system, the sampling rate remains unchanged but the bandwidth changes require different sub-filter coefficients to be set. In order to simplify the design, the coefficient length of each sub-filter can be fixed during the design, and the coefficient value can be configured and updated. The delay module ZM(N-1)/2 can also be dynamically adjusted without reloading each time the bandwidth changes. FPGA Bit file.

例如，假设子滤波器有三个，各个子滤波器原带宽对应的系数分别为59阶、64阶及34阶，当目标通信***的总带宽发生变化时，需要重新调试确定这三个子滤波器的系数，假设这三个子滤波器重新调试得到的系数分别变为71阶、50阶及40阶；由于第一个子滤波器在原带宽对应的系数59阶小于总带宽变化后的系数71阶，则第一个子滤波器的系数选择71阶；由于第二个子滤波器在原带宽对应的系数64阶大于总带宽变化后的系数50阶，则第二个子滤波器的系数选择64阶；由于第三个子滤波器在原带宽对应的系数34阶小于总带宽变化后的系数40阶，则第三个子滤波器的系数选择40阶，即同一个子滤波器在总带宽前后变化过程中，哪个系数长度较长选哪个，从而重新得到由71阶、64阶及40阶组成的三个子滤波器的系数组。For example, suppose there are three sub-filters, and the coefficients corresponding to the original bandwidth of each sub-filter are 59th, 64th, and 34th respectively. When the total bandwidth of the target communication system changes, it is necessary to re-adjust and determine the parameters of these three subfilters. The coefficients, assuming that the coefficients obtained from the re-adjustment of the three sub-filters become 71, 50, and 40 respectively; since the coefficient of the first sub-filter corresponding to the original bandwidth of the 59 order is smaller than the coefficient of the 71 order after the total bandwidth change, then The coefficient of the first sub-filter is selected to order 71; since the coefficient of the second sub-filter corresponding to the original bandwidth of the 64-order is greater than the coefficient of the 50-order after the total bandwidth change, the coefficient of the second sub-filter is selected to be the order of 64; The coefficient of order 34 corresponding to the original bandwidth of each sub-filter is smaller than the coefficient of order 40 after the total bandwidth is changed, then the coefficient of the third sub-filter is selected to order 40, that is, when the same sub-filter changes before and after the total bandwidth, which coefficient is longer Which one to choose, so as to get the coefficient group of the three sub-filters composed of 71, 64, and 40 orders again.

本公开提供的滤波器系数确定方法，当目标通信***传输的采样率不变，且总带宽发生变化时，重新调试得到各子滤波器的系数，将各子滤波器重新调试得到的系数与原带宽对应的系数进行系数长度比较，选取系数长度较长的系数作为总带宽变化后的子滤波器的系数，以重新得到由各子滤波器系数组成的系数组，从而为了兼容滤波器系数较短时，计算较长的滤波器系数长度与较短的子滤波器系数长度的差值，将差值的一半分别添加在较短滤波器系数的起始和结束处，从而使不同长度的滤波器系数长度保持一致，实现动态调整子滤波器的系数，不需要每次带宽变化时重新加载FPGA Bit文件，显著减少开发工作量。In the method for determining filter coefficients provided by the present disclosure, when the sampling rate transmitted by the target communication system is unchanged and the total bandwidth changes, the coefficients of each sub-filter are re-tuned, and the coefficients obtained from the re-tune of each sub-filter are compared with the original The coefficients corresponding to the bandwidth are compared with the coefficient length, and the coefficient with the longer coefficient length is selected as the coefficient of the sub-filter after the total bandwidth is changed, so as to retrieve the coefficient group composed of the coefficients of the sub-filters, so as to be compatible with the shorter filter coefficients. Calculate the difference between the longer filter coefficient length and the shorter sub-filter coefficient length, and add half of the difference at the beginning and end of the shorter filter coefficient, so that filters of different lengths The coefficient length is kept the same to realize the dynamic adjustment of the coefficients of the sub-filters, and there is no need to reload the FPGA Bit file every time the bandwidth changes, which significantly reduces the development workload.

在一实施例中，得到各个子滤波器所对应的子滤波参数的步骤，可具体包括：In an embodiment, the step of obtaining the sub-filter parameters corresponding to each sub-filter may specifically include:

根据子滤波器每次调试得到的子滤波调试参数计算各个子滤波器的调试系数；Calculate the tuning coefficients of each sub-filter according to the sub-filter tuning parameters obtained during each tuning of the sub-filter;

当各个子滤波器的调试系数长度之和最小时，将各个子滤波器当前调试得到的子滤波调试参数作为各个子滤波器所对应的子滤波参数。When the sum of the lengths of the tuning coefficients of each sub-filter is the smallest, the sub-filter tuning parameter currently debugged for each sub-filter is used as the sub-filter parameter corresponding to each sub-filter.

在本实施例中，确定各个子滤波器所对应的子滤波参数时，根据子滤波器每次调试得到的子滤波调试参数计算各子滤波器的调试系数，并计算所有子滤波器当前调试的调试系数长度之和，判断当前调试中，所有子滤波器的调试系数长度之和是否为所有调试的最小值，当子滤波器的调试系数长度之和最小时，将各个子滤波器当前调试得到的子滤波调试参数作为各个子滤波器所对应的子滤波参数，从而得到器件资源最优的子滤波器系数所对应的子滤波参数。In this embodiment, when determining the sub-filter parameters corresponding to each sub-filter, the commissioning coefficients of each sub-filter are calculated according to the sub-filter commissioning parameters obtained each time the sub-filter is commissioned, and the current commissioning parameters of all sub-filters are calculated. The sum of the lengths of the tuning coefficients, to determine whether the sum of the lengths of the tuning coefficients of all the sub-filters is the minimum value of all the tunings during the current tuning. When the sum of the lengths of the tuning coefficients of the sub-filters is the smallest, the current tuning of each sub-filter is obtained. The sub-filter debugging parameters of is used as the sub-filter parameters corresponding to each sub-filter, so as to obtain the sub-filter parameters corresponding to the sub-filter coefficients with the optimal device resources.

下面通过具体实施例说明对多个子滤波器进行调试，以确定各子滤波器的调试系数的具体过程。The following specific embodiments illustrate the specific process of debugging multiple sub-filters to determine the debugging coefficients of each sub-filter.

在一实施例中，在步骤S12中，所述子滤波器包括第一子滤波器，基于所述第一滤波参数对多个子滤波器进行调试的步骤，可具体包括：In an embodiment, in step S12, the sub-filter includes a first sub-filter, and the step of debugging multiple sub-filters based on the first filter parameter may specifically include:

设定第一子滤波器的初始插值倍数，确定该初始插值倍数对应的第一子滤波器的初始通带截止频率和初始阻带起始频率；Setting the initial interpolation multiple of the first subfilter, and determining the initial passband cutoff frequency and the initial stopband start frequency of the first subfilter corresponding to the initial interpolation multiple;

判断所述初始通带截止频率是否小于所述初始阻带起始频率；Judging whether the initial passband cutoff frequency is less than the initial stopband start frequency;

若所述初始通带截止频率小于所述初始阻带起始频率时，根据第一预设算法计算各子滤波器的调试通带截止频率和调试阻带起始频率；If the initial passband cutoff frequency is less than the initial stopband start frequency, calculate the debug passband cutoff frequency and the debug stopband start frequency of each sub-filter according to the first preset algorithm;

若否，则根据第二预设算法计算各子滤波器的调试通带截止频率和调试阻带起始频率；If not, calculate the cut-off frequency of the cut-off frequency of each sub-filter and the start frequency of the cut-off frequency of each sub-filter according to the second preset algorithm;

根据子滤波器每次调试得到的子滤波调试参数计算各子滤波器的调试系数的步骤，包括：The steps of calculating the commissioning coefficients of each sub-filter according to the sub-filter commissioning parameters obtained during each commissioning of the sub-filter include:

根据各子滤波器每次调试得到的调试通带截止频率和调试阻带起始频率计算各子滤波器的调试系数。Calculate the debugging coefficient of each sub-filter according to the cut-off frequency of the debugging pass band and the starting frequency of the debugging stop-band obtained during each debugging of each sub-filter.

本实施例可包括三个子滤波器，第一子滤波器、第二子滤波器和第三子滤波器，其中，第一子滤波器为原型成型滤波器Ha(z)、第二子滤波器和第三子滤波器分别为屏蔽滤波器Hma(z)和Hmc(z)。对子滤波器进行调试时，可设定原型成型滤波器的初始插值倍数，确定该初始插值倍数对应的第一子滤波器的初始通带截止频率和初始阻带起始频率，并判断所述初始通带截止频率是否小于所述初始阻带起始频率。当所述初始通带截止频率小于初始阻带起始频率，且皆大于零小于π时，则根据第一预设算法计算各子滤波器的调试通带截止频率和调试阻带起始频率；当所述初始通带截止频率大于或等于初始阻带起始频率，且皆大于零小于π时，则采用第二预设算法计算各子滤波器的调试通带截止频率和调试阻带起始频率，从而根据各子滤波器每次调试得到的调试通带截止频率和调试阻带起始频率设定各子滤波器的通带纹波和阻带衰减，利用MATLAB函数firpmord计算3个滤波器Ha(z)、Hma(z)、Hmc(z)的调试系数，当3个子滤波器的调试系数长度之和最小时，得到3个子滤波器对应的系数。This embodiment may include three sub-filters, a first sub-filter, a second sub-filter, and a third sub-filter. The first sub-filter is the prototype shaping filter Ha(z) and the second sub-filter. The and third sub-filters are mask filters Hma(z) and Hmc(z), respectively. When debugging the sub-filter, you can set the initial interpolation multiple of the prototype shaping filter, determine the initial pass-band cut-off frequency and initial stop-band start frequency of the first sub-filter corresponding to the initial interpolation multiple, and determine the Whether the initial passband cutoff frequency is less than the initial stopband start frequency. When the initial passband cutoff frequency is less than the initial stopband start frequency, and both are greater than zero and less than π, then calculate the debug passband cutoff frequency and the debug stopband start frequency of each sub-filter according to the first preset algorithm; When the initial passband cut-off frequency is greater than or equal to the initial stopband start frequency, and both are greater than zero and less than π, the second preset algorithm is used to calculate the debug passband cutoff frequency and the debug stopband start of each sub-filter Frequency, so as to set the pass-band ripple and stop-band attenuation of each sub-filter according to the cut-off frequency of the debug pass-band and the start frequency of the debug stop-band obtained by each sub-filter each time the filter is debugged, and use the MATLAB function firpmord to calculate 3 filters For the tuning coefficients of Ha(z), Hma(z), and Hmc(z), when the sum of the lengths of the tuning coefficients of the three sub-filters is the smallest, the coefficients corresponding to the three sub-filters are obtained.

在一实施例中，根据第一预设算法计算各子滤波器的调试通带截止频率和调试阻带起始频率的步骤，可具体包括：In an embodiment, the step of calculating the cut-off frequency of the tuning passband and the starting frequency of the tuning stop-band of each sub-filter according to the first preset algorithm may specifically include:

根据第一滤波参数及每次调试设定的调试插值倍数计算第一调试参数；Calculate the first debugging parameter according to the first filtering parameter and the debugging interpolation multiple set for each debugging;

根据所述第一滤波参数、第一调试参数及调试插值倍数计算第一子滤波器的调试通带截止频率和调试阻带起始频率；Calculating the cut-off frequency of the debugging passband and the starting frequency of the debugging stop-band of the first sub-filter according to the first filter parameter, the first debugging parameter, and the debugging interpolation multiple;

根据所述第一调试参数、调试插值倍数、第一子滤波器的调试通带截止频率和调试阻带起始频率计算其他子滤波器的调试通带截止频率和调试阻带起始频率。According to the first tuning parameter, the tuning interpolation multiple, the tuning passband cutoff frequency of the first sub-filter, and the tuning stopband start frequency, the tuning passband cutoff frequency and the tuning stopband start frequency of other subfilters are calculated.

在本实施例中，调试时，需根据各子滤波器的响应设定调试插值倍数，以根据第一滤波参数及每次调试设定的调试插值倍数计算第一调试参数，具体可根据如下公式计算第一调试参数:In this embodiment, during debugging, it is necessary to set the debugging interpolation multiple according to the response of each sub-filter, so as to calculate the first debugging parameter according to the first filter parameter and the debugging interpolation multiple set for each debugging, which can be specifically based on the following formula Calculate the first debugging parameters:

m1＝floor(wp*M/(2*π))；m1=floor(wp*M/(2*π));

其中，所述m1为第一调试参数，所述wp为第一滤波参数的通带截止频率，floor(x)表示小于或等于x的最大整数，M为调试插值倍数。Wherein, the m1 is the first tuning parameter, the wp is the passband cut-off frequency of the first filter parameter, floor(x) represents the largest integer less than or equal to x, and M is the tuning interpolation multiple.

然后根据计算得到的第一滤波参数、第一调试参数及调试插值倍数计算第一子滤波器的调试通带截止频率和调试阻带起始频率，具体可根据如下公式分别计算第一子滤波器的调试通带截止频率和调试阻带起始频率:Then calculate the cut-off frequency of the first sub-filter and the start frequency of the stop-band according to the calculated first filter parameter, first adjustment parameter and adjustment interpolation multiple. Specifically, the first sub-filter can be calculated separately according to the following formula The cut-off frequency of the debug passband and the start frequency of the debug stopband:

θ＝wp*M-2*m1*π；θ=wp*M-2*m1*π;

其中，θ为第一子滤波器的调试通带截止频率，

为第一子滤波器的调试阻带起始频率，ws为第一滤波参数的阻带起始频率。 Among them, θ is the cutoff frequency of the first sub-filter's debugging passband,

Is the start frequency of the tuning stopband of the first sub-filter, and ws is the start frequency of the stopband of the first filter parameter.

在一实施例中，所述子滤波器还包括第二子滤波器，所述第二子滤波器为屏蔽滤波器Hma(z)，计算该屏蔽滤波器Hma(z)的调试通带截止频率和调试阻带起始频率时，可通过如下公式计算：In an embodiment, the sub-filter further includes a second sub-filter, and the second sub-filter is a masking filter Hma(z), and the cutoff frequency of the debugging passband of the masking filter Hma(z) is calculated When debugging the stop band start frequency, it can be calculated by the following formula:

wpma＝(2*m1*π+θ)/M；wpma=(2*m1*π+θ)/M;

其中，wpma为第二子滤波器的调试通带截止频率，wsma为第二子滤波器的调试阻带起始频率。Among them, wpma is the cut-off frequency of the debugging passband of the second sub-filter, and wsma is the start frequency of the debugging stop-band of the second sub-filter.

在一实施例中，所述子滤波器还包括第三子滤波器，所述第三子滤波器为屏蔽滤波器Hmc(z)，计算该屏蔽滤波器Hmc(z)的调试通带截止频率和调试阻带起始频率时，可通过如下公式计算：In an embodiment, the sub-filter further includes a third sub-filter, and the third sub-filter is a masking filter Hmc(z), and the cut-off frequency of the debugging passband of the masking filter Hmc(z) is calculated When debugging the stop band start frequency, it can be calculated by the following formula:

wpmc＝(2*m1*π-θ)/M；wpmc=(2*m1*π-θ)/M;

其中，wpmc为第三子滤波器的调试通带截止频率，wsmc为第三子滤波器的调试阻带起始频率。Among them, wpmc is the cut-off frequency of the debugging passband of the third sub-filter, and wsmc is the start frequency of the debugging stop-band of the third sub-filter.

在一实施例中，根据第二预设算法计算各子滤波器的调试通带截止频率和调试阻带起始频率的步骤，包括：In an embodiment, the step of calculating the cut-off frequency of the tuning passband and the starting frequency of the tuning stop-band of each sub-filter according to the second preset algorithm includes:

根据第一滤波参数及每次调试设定的调试插值倍数计算第二调试参数；Calculate the second debugging parameter according to the first filtering parameter and the debugging interpolation multiple set for each debugging;

根据所述第一滤波参数、第二调试参数及调试插值倍数计算第一子滤波器的调试通带截止频率和调试阻带起始频率；Calculating the cut-off frequency of the debugging passband and the starting frequency of the debugging stop-band of the first sub-filter according to the first filter parameter, the second debugging parameter, and the debugging interpolation multiple;

在本实施例中，调试时，需根据各子滤波器的响应设定调试插值倍数，以根据第一滤波参数及每次调试设定的调试插值倍数计算第二调试参数，具体可根据如下公式计算第二调试参数:In this embodiment, during debugging, it is necessary to set the debugging interpolation multiple according to the response of each sub-filter, so as to calculate the second debugging parameter according to the first filter parameter and the debugging interpolation multiple set for each debugging, which can be specifically based on the following formula Calculate the second debugging parameters:

m2＝ceil(ws*M/(2*π))；m2=ceil(ws*M/(2*π));

其中，所述m2为第二调试参数，所述ws为第一滤波参数的阻带截止频率，ceil(x)表示大于或等于x的最小整数,M为调试插值倍数。Wherein, the m2 is the second tuning parameter, the ws is the stopband cut-off frequency of the first filter parameter, ceil(x) represents the smallest integer greater than or equal to x, and M is the tuning interpolation multiple.

然后根据计算得到的第一滤波参数、第二调试参数及调试插值倍数计算第一子滤波器的调试通带截止频率和调试阻带起始频率，所述第一子滤波器为原型成型滤波器Ha(z)，具体可根据如下公式分别计算第一子滤波器的调试通带截止频率和调试阻带起始频率:Then calculate the cut-off frequency of the first sub-filter and the start frequency of the stop-band of the first sub-filter according to the calculated first filter parameter, the second debugging parameter, and the debugging interpolation multiple. The first sub-filter is a prototype shaping filter. Ha(z), the cut-off frequency of the first sub-filter and the start frequency of the stop-band can be calculated separately according to the following formula:

θ＝2*m2*π-ws*M；θ=2*m2*π-ws*M;

其中，θ为第一子滤波器的调试通带截止频率，

为第一子滤波器的调试阻带起始频率，wp为第一滤波参数的通带截止频率。 Among them, θ is the cutoff frequency of the first sub-filter's debugging passband,

Is the start frequency of the tuning stopband of the first sub-filter, and wp is the cutoff frequency of the passband of the first filter parameter.

wsma＝(2*m2*π-θ)/M；wsma=(2*m2*π-θ)/M;

wsmc＝(2*m2*π+θ)/M；wsmc=(2*m2*π+θ)/M;

为了更好地理解本公开，下面以一个具体的实施例来对本技术方案的原理进行说明：In order to better understand the present disclosure, the following uses a specific embodiment to illustrate the principle of the technical solution:

如图4所示，图4为一数字DAS***中最简单的下行链路处理框图，其AD采样率为153.6Msps，我们可选择光纤基带传输采样率为76.8Msps，此时仅需一个半带滤波器就可实现采样率转换。实际数字DAS***中AD采样率还可采用其他采样率，可以通过分数倍滤波器实现采样率变换到基带光纤传输速率。As shown in Figure 4, Figure 4 is the simplest downlink processing block diagram in a digital DAS system. The AD sampling rate is 153.6Msps. We can choose the optical fiber baseband transmission sampling rate to be 76.8Msps. At this time, only one half-band is needed. The filter can realize the sampling rate conversion. In the actual digital DAS system, the AD sampling rate can also adopt other sampling rates, and the sampling rate can be converted to the baseband optical fiber transmission rate through a fractional filter.

在数字DAS***中，假设需要4G LTE频段宽带接入数字DAS***支持60MHz，基带传输采样率为76.8Msps，可设计一低通滤波器，该低通滤波器的通带截止频率为29MHz、阻带起始频率为30MHz、通带纹波为0.1dB、阻带抑制为30dB，采用FIR(Finite Impulse Response，有限长单位冲激响应)等纹波设计，低通滤波器阶数为162阶。假定FPGA工作时钟为307.2MHz，利用滤波器的对称性，该低通滤波器实现IQ二路约需要42个乘法器。In the digital DAS system, assuming that 4G LTE frequency band broadband access is required, the digital DAS system supports 60MHz, and the baseband transmission sampling rate is 76.8Msps. A low-pass filter can be designed. The passband cut-off frequency of the low-pass filter is 29MHz, The band start frequency is 30MHz, the passband ripple is 0.1dB, and the stopband suppression is 30dB. It adopts FIR (Finite Impulse Response, finite-length unit impulse response) and other ripple designs. The low-pass filter order is 162. Assuming that the FPGA working clock is 307.2MHz, using the symmetry of the filter, the low-pass filter needs about 42 multipliers to implement IQ two-way.

在现有数字DAS***中要实现从4G LTE20MHz*3支持到3个NR20MHz带宽，采用传统方法我们设计一个通带截止频率为29.54MHz、阻带起始频率为30MHz、通带纹波为0.1Db、阻带抑制为40Db的目标滤波器，采用FIR等纹波设计，目标滤波器阶数为353阶，如图5所示，假定FPGA工作时钟为307.2MHz，利用滤波器的对称性，采用常规方式实现IQ二路约需要89个乘法器。In the existing digital DAS system, it is necessary to realize from 4G LTE20MHz*3 support to 3 NR20MHz bandwidths. Using traditional methods, we design a passband cut-off frequency of 29.54MHz, stopband start frequency of 30MHz, and passband ripple of 0.1Db , The stop-band suppression is the target filter of 40Db, using FIR and other ripple design, the target filter order is 353, as shown in Figure 5, assuming that the FPGA working clock is 307.2MHz, using the symmetry of the filter, using conventional About 89 multipliers are needed to implement IQ two-way.

由上可以明显看到，按照传统方法，FPGA资源乘法器要多一倍以上，某些情况下原有设备资源余量不够，限制了设备从4G LTE升级到5G NR的可能性。因此，如图6所述，本公开利用滤波器系数确定方法确定基于FRM技术的下行链路中的子滤波器系数，并将采用该滤波器系数确定方法确定的FRM滤波器配置在该数字DAS***的下行链路中，由于基于FRM技术上行链路是下行链路的逆过程，在此不再具体赘述，下面主要针对下行链路进行分析和仿真。It is obvious from the above that according to the traditional method, the FPGA resource multiplier is more than doubled. In some cases, the original equipment resource margin is insufficient, which limits the possibility of upgrading the equipment from 4G LTE to 5G NR. Therefore, as shown in FIG. 6, the present disclosure uses the filter coefficient determination method to determine the sub-filter coefficients in the downlink based on the FRM technology, and configures the FRM filter determined by the filter coefficient determination method in the digital DAS. In the downlink of the system, since the uplink based on the FRM technology is the inverse process of the downlink, it will not be described in detail here. The following analysis and simulation are mainly performed on the downlink.

如图7所示，仅需要3个子滤波器及一个时延模块就可实现原来一个352阶滤波器的效果，其中上支路原型成型滤波器Ha(z)系数为59阶，Ha(ZM)为上支路原型成型滤波器Ha(z)插值M倍(示例内插因子M为6)滤波器；上支路屏蔽滤波器Hma(Z)滤波器阶数为34阶，下支路屏蔽滤波器Hmc(Z)滤波器阶数为64阶，均为单速率滤波器，下支路延时模块Z-M(N-1)/2，其中N为Ha(z)系数长度等于59。如图8a和8b所示，图8a和8b分别是原型滤波器Ha(z)及内插6倍Ha(ZM)后的频率响应图，可以明显看到插值后滤波器Ha(ZM)的过渡带明显变得更陡峭，对应的阶数更高。如图9所示，图9是屏蔽滤波器Hma(Z)的一种具体响应，其主要用于滤除上分支链路Ha(ZM)多余的频率成分。如图10所示，图10是屏蔽滤波器Hmc(Z)的一种具体响应，用于滤除信号经过时延调整模块Z-M(N-1)/2与Ha(Z ^M)相减后的支路中多的频率成分。如图11所示，图11是一种基于FRM技术的滤波器总响应，可见该滤波器响应与基于传统方法设计的滤波器响应基本一致。 As shown in Figure 7, only 3 sub-filters and a delay module are needed to achieve the effect of the original 352-order filter. The upper branch prototype shaping filter Ha(z) coefficient is 59-order, Ha(ZM) The upper branch prototype shaping filter Ha(z) interpolation M times (the example interpolation factor M is 6) filter; the upper branch shielding filter Hma(Z) filter order is 34 orders, and the lower branch shielding filter The order of the Hmc(Z) filter is 64, all of which are single-rate filters. The lower branch delay module is ZM(N-1)/2, where N is the length of the Ha(z) coefficient equal to 59. As shown in Figures 8a and 8b, Figures 8a and 8b are the frequency response diagrams of the prototype filter Ha (z) and the interpolation 6 times Ha (ZM) respectively. You can clearly see the transition of the interpolated filter Ha (ZM) The band becomes significantly steeper, and the corresponding order is higher. As shown in Fig. 9, Fig. 9 is a specific response of the shielding filter Hma(Z), which is mainly used to filter the redundant frequency components of the upper branch link Ha(ZM). As shown in Figure 10, Figure 10 is a specific response of the shielding filter Hmc(Z), which is used to filter out the signal after the delay adjustment module ZM(N-1)/2 and Ha(Z ^M ) are subtracted Many frequency components in the branch. As shown in Fig. 11, Fig. 11 shows the total response of a filter based on FRM technology. It can be seen that the filter response is basically the same as the filter response designed based on traditional methods.

图12是基于已有FIR core的IFIR滤波器参数配置，基于已有FPGA开发工具调用FIRcore快速实现Ha(Z ^M)滤波；图中三个子滤波器Ha(ZM)、Hma(Z)、Hmc(Z)在实现时均可以直接调用FIR compiler IPcore来实现。 Figure 12 is the IFIR filter parameter configuration based on the existing FIR core, based on the existing FPGA development tools to call FIRcore to quickly implement Ha(Z ^M ) filtering; the three sub-filters in the figure Ha(ZM), Hma(Z), Hmc( Z) FIR compiler IPcore can be called directly to realize it.

如下表所示，分别出示了原有4G LTE所需FPGA乘法器资源、采用常规方式支持5G NR所需的FPGA乘法器资源及采用本技术方案支持5G NR所需的FPGA乘法器资源。As shown in the following table, the original FPGA multiplier resources required for 4G LTE, the FPGA multiplier resources required to support 5G NR using conventional methods, and the FPGA multiplier resources required to support 5G NR using this technical solution are shown respectively.

原有4G LTE所需FPGA乘法器资源FPGA multiplier resources required by the original 4G LTE

常规方式支持5G NR所需FPGA乘法器资源Conventional method to support 5G NR required FPGA multiplier resources

基于FRM技术支持5G NR所需FPGA乘法器资源FPGA multiplier resources required to support 5G NR based on FRM technology

由上可见，基于FRM技术的本技术方案支持5G NR带宽可变滤波器，所需资源(40个乘法器)与原有4G LTE资源(41个乘法器)相当，比常规方式支持5G NR所需的FPGA乘法器资源少了一半。因此，当目标通信***需要不同的带宽，我们仅需改动3个滤波器Ha(ZM)、Hma(Z)、Hmc(Z)系数及下支路时延模块Z-M(N-1)/2参数就可以实现将多个子滤波器替换目标滤波器，并实现相同的滤波效果，从而在已部署的目标通信***不改动原器件资源的情形下，实现将现有移动通信网络升级到新一代移动通信网络，以提高频谱利用率和通信速率。It can be seen from the above that this technical solution based on the FRM technology supports 5G NR bandwidth variable filters, and the required resources (40 multipliers) are equivalent to the original 4G LTE resources (41 multipliers), and are better than the conventional method that supports 5G NR. The FPGA multiplier resources required are reduced by half. Therefore, when the target communication system requires different bandwidths, we only need to modify the three filters Ha(ZM), Hma(Z), Hmc(Z) coefficients and the lower branch delay module ZM(N-1)/2 parameters It is possible to replace multiple sub-filters with the target filter and achieve the same filtering effect, so that the existing mobile communication network can be upgraded to a new generation of mobile communication without changing the original device resources in the deployed target communication system Network to improve spectrum utilization and communication speed.

如图13所示，图13是一种滤波器系数确定装置的结构框图，在这种架构中，只需要通过配置Ha(Z ^M)的插值倍数M、时延调整模块Z-M(N-1)/2、上分支屏蔽滤波器Hma(z)和下分支屏蔽滤波器Hmc(z)的系数就可以实现对不同带宽的支持，从而快速的应用到不同带宽要求的数字DAS***中。 As shown in Figure 13, Figure 13 is a structural block diagram of a filter coefficient determination device. In this architecture, it is only necessary to configure ^{the interpolation multiple M of Ha(Z M} ) and the delay adjustment module ZM(N-1) /2. The coefficients of the upper-branch shielding filter Hma(z) and the lower-branch shielding filter Hmc(z) can support different bandwidths, so that they can be quickly applied to digital DAS systems with different bandwidth requirements.

如图14所示，本公开提供的一种滤波器系数确定装置，包括：获取模块11，配置为获取目标通信***所支持的目标滤波器的第一滤波参数；调试模块12，配置为基于所述第一滤波参数对多个子滤波器进行调试，确定达到与所述目标滤波器相同的滤波效果时，得到各个子滤波器所对应的子滤波参数；确定模块13，配置为根据所述子滤波参数确定各子滤波器的系数。As shown in FIG. 14, a device for determining filter coefficients provided by the present disclosure includes: an obtaining module 11 configured to obtain the first filter parameter of a target filter supported by the target communication system; and a debugging module 12 configured to obtain the first filter parameter of the target filter supported by the target communication system; The first filter parameter is used to debug multiple sub-filters, and when it is determined that the same filtering effect as the target filter is achieved, the sub-filter parameters corresponding to each sub-filter are obtained; the determining module 13 is configured to be configured according to the sub-filter The parameters determine the coefficients of each sub-filter.

本公开提供的滤波器系数确定装置，通过获取目标通信***所支持的目标滤波器的第一滤波参数，基于第一滤波参数对多个子滤波器进行调试，确定达到与所述目标滤波器相同的滤波效果时，得到各个子滤波器所对应的子滤波参数，并根据所述子滤波参数确定各子滤波器的系数，以后续利用各子滤波器的系数，在原FPGA芯片上实现信号的乘积累加，实现将多个子滤波器替换目标滤波器，并实现相同的滤波效果，从而在已部署的目标通信***不改动原器件资源的情形下，实现将现有移动通信网络升级到新一代移动通信网络，以提高频谱利用率和通信速率。The filter coefficient determination device provided by the present disclosure obtains the first filter parameter of the target filter supported by the target communication system, and debugs multiple sub-filters based on the first filter parameter, and determines that the filter coefficient is the same as the target filter. During the filtering effect, the sub-filter parameters corresponding to each sub-filter are obtained, and the coefficients of each sub-filter are determined according to the sub-filter parameters, and the coefficients of each sub-filter are subsequently used to realize signal multiplication and accumulation on the original FPGA chip. , To achieve multiple sub-filters to replace the target filter, and achieve the same filtering effect, so that the existing mobile communication network can be upgraded to a new generation mobile communication network without changing the original device resources in the deployed target communication system , In order to improve spectrum utilization and communication speed.

关于上述实施例中的装置，其中各个模块执行操作的具体方式已经在有关该方法的实施例中进行了详细描述，此处将不做详细阐述说明。Regarding the device in the foregoing embodiment, the specific manner in which each module performs operation has been described in detail in the embodiment of the method, and detailed description will not be given here.

本公开提供的一种数字DAS***，包括接入单元、扩展单元和远端单元，所述接入单元、扩展单元和远端单元中的至少一个滤波器系数采用所述滤波器系数确定方法进行确定。A digital DAS system provided by the present disclosure includes an access unit, an extension unit, and a remote unit. At least one filter coefficient of the access unit, the extension unit, and the remote unit is performed using the filter coefficient determination method. determine.

本领域普通技术人员可以理解实现上述实施例方法中的全部或部分流程，是可以通过计算机程序来指令相关的硬件来完成，该计算机程序可存储于一存储介质中，该程序在执行时，可包括如上述各方法的实施例的流程。其中，前述的存储介质可为磁碟、光盘、只读存储记忆体(Read-Only Memory，ROM)等非易失性存储介质，或随机存储记忆体(Random Access Memory，RAM)等。A person of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing relevant hardware through a computer program. The computer program can be stored in a storage medium. When the program is executed, it can be Including the flow of the embodiments of the above-mentioned methods. Among them, the aforementioned storage medium may be a non-volatile storage medium such as a magnetic disk, an optical disc, a read-only memory (Read-Only Memory, ROM), or a random access memory (Random Access Memory, RAM), etc.

综合上述实施例可知，本公开最大的有益效果在于：Based on the foregoing embodiments, it can be seen that the greatest beneficial effect of the present disclosure lies in:

本公开提供的滤波器系数确定方法、装置及数字DAS***，通过获取目标通信***所支持的目标滤波器的第一滤波参数，基于第一滤波参数对多个子滤波器进行调试，确定达到与所述目标滤波器相同的滤波效果时，得到各个子滤波器所对应的子滤波参数，并根据所述子滤波参数确定各子滤波器的系数，以后续利用各子滤波器的系数，在原FPGA芯片上实现信号的乘积累加，实现将多个子滤波器替换目标滤波器，并实现相同的滤波效果，从而在已部署的目标通信***不改动原器件资源的情形下，实现将现有移动通信网络升级到新一代移动通信网络，以提高频谱利用率和通信速率。The method and device for determining filter coefficients and the digital DAS system provided by the present disclosure obtain the first filter parameter of the target filter supported by the target communication system, and debug multiple sub-filters based on the first filter parameter to determine that the When the target filter has the same filtering effect, the sub-filter parameters corresponding to each sub-filter are obtained, and the coefficients of each sub-filter are determined according to the sub-filter parameters, so that the coefficients of each sub-filter can be used in the original FPGA chip. Multiplying, accumulating, and adding signals, realizing multiple sub-filters to replace the target filter, and achieving the same filtering effect, so that the existing mobile communication network can be upgraded without changing the original device resources in the deployed target communication system To the new generation of mobile communication networks to improve spectrum utilization and communication speed.

本公开实施例还提供一种计算机存储介质，其中，该计算机存储介质可存储有程序，该程序执行时可实现上文实施例提供的滤波器系数确定方法的各实现方式中的部分或全部步骤。The embodiments of the present disclosure also provide a computer storage medium, wherein the computer storage medium may store a program, and when the program is executed, some or all of the steps in each implementation manner of the filter coefficient determination method provided in the above embodiments can be implemented .

工业实用性Industrial applicability

本公开公开的滤波器系数确定方法包括：获取目标通信***所支持的目标滤波器的第一滤波参数；基于第一滤波参数对多个子滤波器进行调试，确定达到与目标滤波器相同的滤波效果时，得到各个子滤波器所对应的子滤波参数；根据子滤波参数确定各子滤波器的系数。本公开实现了在已部署的目标通信***不改动原器件资源的情形下，将现有移动通信网络升级到新一代移动通信网络，以提高频谱利用率和通信速率，具有很强的工业实用性。The method for determining filter coefficients disclosed in the present disclosure includes: acquiring a first filter parameter of a target filter supported by a target communication system; debugging a plurality of sub-filters based on the first filter parameter, and determining to achieve the same filtering effect as the target filter When, the sub-filter parameters corresponding to each sub-filter are obtained; the coefficients of each sub-filter are determined according to the sub-filter parameters. The present disclosure realizes that the existing mobile communication network is upgraded to a new generation mobile communication network under the condition that the deployed target communication system does not change the original device resources, so as to improve the spectrum utilization rate and the communication rate, and has strong industrial applicability. .

Claims

一种滤波器系数确定方法，包括如下步骤：A method for determining filter coefficients includes the following steps:

获取目标通信***所支持的目标滤波器的第一滤波参数；Acquiring the first filter parameter of the target filter supported by the target communication system;

基于所述第一滤波参数对多个子滤波器进行调试，确定达到与所述目标滤波器相同的滤波效果时，得到各个子滤波器所对应的子滤波参数；Debug multiple sub-filters based on the first filter parameter, and obtain the sub-filter parameters corresponding to each sub-filter when it is determined that the same filtering effect as the target filter is achieved;

根据所述子滤波参数确定各子滤波器的系数。The coefficients of each sub-filter are determined according to the sub-filter parameters.
根据权利要求1所述的滤波器系数确定方法，其中，得到各个子滤波器所对应的子滤波参数的步骤，包括：The method for determining filter coefficients according to claim 1, wherein the step of obtaining the sub-filter parameters corresponding to each sub-filter comprises:

根据子滤波器每次调试得到的子滤波调试参数计算各个子滤波器的调试系数；Calculate the tuning coefficients of each sub-filter according to the sub-filter tuning parameters obtained during each tuning of the sub-filter;

当各个子滤波器的调试系数长度之和最小时，将各个子滤波器当前调试得到的子滤波调试参数作为各个子滤波器所对应的子滤波参数。When the sum of the lengths of the tuning coefficients of each sub-filter is the smallest, the sub-filter tuning parameter currently debugged for each sub-filter is used as the sub-filter parameter corresponding to each sub-filter.
根据权利要求2所述的滤波器系数确定方法，其中，所述子滤波器包括第一子滤波器，基于所述第一滤波参数对多个子滤波器进行调试的步骤，包括：The method for determining filter coefficients according to claim 2, wherein the sub-filter comprises a first sub-filter, and the step of debugging a plurality of sub-filters based on the first filter parameter comprises:

设定第一子滤波器的初始插值倍数，确定该初始插值倍数对应的第一子滤波器的初始通带截止频率和初始阻带起始频率；Setting the initial interpolation multiple of the first subfilter, and determining the initial passband cutoff frequency and the initial stopband start frequency of the first subfilter corresponding to the initial interpolation multiple;

判断所述初始通带截止频率是否小于所述初始阻带起始频率；Judging whether the initial passband cutoff frequency is less than the initial stopband start frequency;

若所述初始通带截止频率小于所述初始阻带起始频率时，根据第一预设算法计算各子滤波器的调试通带截止频率和调试阻带起始频率；If the initial passband cutoff frequency is less than the initial stopband start frequency, calculate the debug passband cutoff frequency and the debug stopband start frequency of each sub-filter according to the first preset algorithm;

若否，则根据第二预设算法计算各子滤波器的调试通带截止频率和调试阻带起始频率；If not, calculate the cut-off frequency of the cut-off frequency of each sub-filter and the start frequency of the cut-off frequency of each sub-filter according to the second preset algorithm;

根据子滤波器每次调试得到的子滤波调试参数计算各子滤波器的调试系数的步骤，包括：The steps of calculating the commissioning coefficients of each sub-filter according to the sub-filter commissioning parameters obtained during each commissioning of the sub-filter include:

根据各子滤波器每次调试得到的调试通带截止频率和调试阻带起始频率计算各子滤波器的调试系数。Calculate the debugging coefficient of each sub-filter according to the cut-off frequency of the debugging pass band and the starting frequency of the debugging stop-band obtained during each debugging of each sub-filter.
根据权利要求3所述的滤波器系数确定方法，其中，根据第一预设算法计算各子滤波器的调试通带截止频率和调试阻带起始频率的步骤，包括：The method for determining filter coefficients according to claim 3, wherein the step of calculating the cut-off frequency of the tuning passband and the starting frequency of the tuning stop-band of each sub-filter according to the first preset algorithm comprises:

根据第一滤波参数及每次调试设定的调试插值倍数计算第一调试参数；Calculate the first debugging parameter according to the first filtering parameter and the debugging interpolation multiple set for each debugging;

根据所述第一滤波参数、第一调试参数及调试插值倍数计算第一子滤波器的调试通带截止频率和调试阻带起始频率；Calculating the cut-off frequency of the debugging passband and the starting frequency of the debugging stop-band of the first sub-filter according to the first filter parameter, the first debugging parameter, and the debugging interpolation multiple;

根据所述第一调试参数、调试插值倍数、第一子滤波器的调试通带截止频率和调试阻带起始频率计算其他子滤波器的调试通带截止频率和调试阻带起始频率。According to the first tuning parameter, the tuning interpolation multiple, the tuning passband cutoff frequency of the first sub-filter, and the tuning stopband start frequency, the tuning passband cutoff frequency and the tuning stopband start frequency of other subfilters are calculated.
根据权利要求3所述的滤波器系数确定方法，其中，根据第二预设算法计算各子滤波器的调试通带截止频率和调试阻带起始频率的步骤，包括：The method for determining filter coefficients according to claim 3, wherein the step of calculating the cut-off frequency of the tuning passband and the starting frequency of the tuning stop-band of each sub-filter according to the second preset algorithm comprises:

根据第一滤波参数及每次调试设定的调试插值倍数计算第二调试参数；Calculate the second debugging parameter according to the first filtering parameter and the debugging interpolation multiple set for each debugging;

根据所述第一滤波参数、第二调试参数及调试插值倍数计算第一子滤波器的调试通带截止频率和调试阻带起始频率；Calculating the cut-off frequency of the debugging passband and the starting frequency of the debugging stop-band of the first sub-filter according to the first filter parameter, the second debugging parameter, and the debugging interpolation multiple;

根据所述第一调试参数、调试插值倍数、第一子滤波器的调试通带截止频率和调试阻带起始频率计算其他子滤波器的调试通带截止频率和调试阻带起始频率。According to the first tuning parameter, the tuning interpolation multiple, the tuning passband cutoff frequency of the first sub-filter, and the tuning stopband start frequency, the tuning passband cutoff frequency and the tuning stopband start frequency of other subfilters are calculated.
根据权利要求1所述的滤波器系数确定方法，还包括：The method for determining filter coefficients according to claim 1, further comprising:

当所述目标通信***传输的采样率不变，且总带宽发生变化时，重新调试得到各子滤波器的系数；When the sampling rate transmitted by the target communication system does not change and the total bandwidth changes, re-adjust to obtain the coefficients of each sub-filter;

将各子滤波器重新调试得到的系数与原带宽对应的系数进行系数长度比较，选取系数长度长的系数作为总带宽变化后的子滤波器的系数，并得到由各子滤波器系数组成的系数组。Compare the coefficient length of the coefficients obtained from the re-adjustment of each sub-filter with the coefficients corresponding to the original bandwidth, select the coefficient with the longer coefficient length as the coefficient of the sub-filter after the total bandwidth change, and obtain the coefficients composed of the coefficients of the sub-filters group.
根据权利要求1所述的滤波器系数确定方法，获取目标通信***所支持的目标滤波器的第一滤波参数之前，还包括：The method for determining filter coefficients according to claim 1, before acquiring the first filter parameter of the target filter supported by the target communication system, further comprising:

根据所述目标通信***的资源剩余情况，将所述目标滤波器替换为多个子滤波器；其中，所述子滤波器为基于FRM的可变带宽成型滤波器。According to the remaining resources of the target communication system, the target filter is replaced with a plurality of sub-filters; wherein, the sub-filters are FRM-based variable bandwidth shaping filters.
根据权利要求1所述的滤波器系数确定方法，其中，根据所述子滤波参数确定各子滤波器的系数的步骤，包括：The method for determining filter coefficients according to claim 1, wherein the step of determining the coefficients of each sub-filter according to the sub-filter parameters comprises:

根据所述子滤波参数设定各子滤波器的通带纹波和阻带衰减；Setting the passband ripple and stopband attenuation of each subfilter according to the subfilter parameters;

根据所述通带纹波和阻带衰减，计算各子滤波器的系数。According to the passband ripple and stopband attenuation, the coefficients of each sub-filter are calculated.
一种滤波器系数确定装置，其特征在于，包括：A device for determining filter coefficients is characterized by comprising:

获取模块，配置为获取目标通信***所支持的目标滤波器的第一滤波参数；An obtaining module, configured to obtain the first filter parameter of the target filter supported by the target communication system;

调试模块，配置为基于所述第一滤波参数对多个子滤波器进行调试，确定达到与所述目标滤波器相同的滤波效果时，得到各个子滤波器所对应的子滤波参数；A debugging module, configured to debug multiple sub-filters based on the first filter parameter, and obtain the sub-filter parameters corresponding to each sub-filter when it is determined that the same filtering effect as the target filter is achieved;

确定模块，配置为根据所述子滤波参数确定各子滤波器的系数。The determining module is configured to determine the coefficients of each sub-filter according to the sub-filter parameters.
一种数字DAS***，包括接入单元、扩展单元和远端单元，其特征在于，所述接入单元、扩展单元和远端单元中的至少一个滤波器系数采用如权利要求1-8中任一项所述的滤波器系数确定方法进行确定。A digital DAS system, comprising an access unit, an extension unit and a remote unit, characterized in that at least one filter coefficient of the access unit, the extension unit and the remote unit adopts any one of the filter coefficients in claims 1-8. The filter coefficient determination method described in one item is determined.