CN104581781B

CN104581781B - Cloud computing system for realizing LTE air interface data analysis

Info

Publication number: CN104581781B
Application number: CN201410821598.0A
Authority: CN
Inventors: 李领; 喻大发
Original assignee: Dingli Corp ltd
Current assignee: Dingli Corp ltd
Priority date: 2014-12-25
Filing date: 2014-12-25
Publication date: 2020-12-15
Anticipated expiration: 2034-12-25
Also published as: CN104581781A

Abstract

The invention discloses a cloud computing system for realizing LTE air interface data analysis, which comprises an antenna, an LTE air interface measuring device and a cloud computing platform. The antenna comprises an antenna unit and a radio frequency connector. The LTE air interface measuring device comprises an LTE air interface demodulation module, a control module and a communication module; the LTE air interface demodulation module comprises a radio frequency module, an LTE uplink receiver and an LTE downlink receiver; the communication module is connected with the control module and also sends the demodulation results of the LTE uplink receiver and the LTE downlink receiver to the cloud computing platform through the Internet for data storage, data operation and data presentation. The cloud computing platform comprises a cloud service module, a cloud computing module and a cloud storage module. By using the method and the device, the air interface communication condition between the LTE network and the LTE terminal can be monitored, and the monitoring data is collected to the cloud platform for analysis and processing.

Description

Cloud computing system for realizing LTE air interface data analysis

Technical Field

The invention relates to the technical field of LTE communication, in particular to a cloud computing system for realizing LTE air interface signal monitoring and data analysis.

Background

According to market statistics, most of the countries and regions around the world have opened LTE networks by the end of 2014, and at least 300 LTE networks are put into practical commercial use. More than 10% of the commercial LTE network is in a TD-LTE mode, and the rest is in an FDD LTE mode.

The core technology adopted by LTE is Orthogonal Frequency Division Multiplexing (OFDM), whose basic principle is to decompose a serial data stream to be transmitted into several parallel sub-data streams of lower rates, then modulate them onto mutually orthogonal sub-carriers, and finally synthesize and output a data rate that is the same as the rate of the serial data stream before decomposition. The OFDM has the main advantages of high frequency spectrum utilization rate, capability of eliminating or reducing intersymbol interference, good narrow-band interference resistance by adopting a frequency hopping method to select orthogonal subcarriers and optimal balance between the frequency spectrum utilization rate and the error rate by adopting an adaptive modulation scheme.

The Core Network (CN) of the LTE is an all-IP-based network, and the whole LTE network architecture is more flat. Compared with the 3G system, the LTE radio access network does not have an RNC, and more radio access functions are implemented in an LTE base station (eNodeB), including physical layer functions, MAC, RLC, PDCP functions, RRC functions, resource scheduling and radio resource management, radio access control, and mobility management.

Therefore, the LTE communication system has better performance than 3G, and is a communication system far more complicated than 3G. From the perspective of mobile operators, the construction and quality optimization of LTE networks will face new challenges:

(1) because the 4G system does not have the RNC, from the perspective of 4G network optimization, the acquisition of uplink signaling and data does not have a standard wired interface, and it is required that uplink signaling data of different 4G base station manufacturers can be directly acquired from a 4G wireless air interface.

(2) The traditional 4G drive test system uses a special 4G drive test terminal for testing, mainly tests the downlink signal coverage of the 4G network and the performance of the 4G network bearing service, and cannot accurately reflect the real user experience of the 4G commercial mobile phone.

(3) The traditional 4G network optimization is divided into foreground optimization and background optimization. The foreground optimization is mainly used for roughly improving the wireless coverage and performance of the 4G base station according to the result of the 4G drive test; the background optimization is mainly used for adjusting and correcting key performance indexes of the network based on network management data output by a 4G base station manufacturer. Foreground optimization and background optimization are generally independently executed by two independent optimization service teams, and due to the complexity of a 4G air interface technology, positioning and solving of 4G network problems often need to combine drive test data and network management data, and an LTE air interface uplink and downlink interaction process is observed simultaneously within a certain time period.

Disclosure of Invention

The invention mainly solves the problems in LTE network optimization, can independently monitor an LTE air interface without depending on any LTE network or LTE terminal manufacturer, and can carry out unified processing by uploading LTE uplink and downlink data simultaneously captured from the air interface to a cloud computing platform so as to objectively present the real communication condition between the LTE network and the LTE terminal.

To solve the above technical problem, an embodiment of the present invention provides a cloud computing system for implementing LTE air interface data analysis, which is implemented as follows:

the utility model provides a realize cloud computing system of LTE air interface data analysis which characterized in that, includes antenna, LTE air interface measuring device and cloud computing platform, wherein:

the antenna comprises an antenna unit and a radio frequency connector;

the LTE air interface measuring device comprises an LTE air interface demodulation module, a control module and a communication module;

the LTE air interface demodulation module comprises a radio frequency module, an LTE uplink receiver and an LTE downlink receiver; the radio frequency module receives an LTE wireless air interface signal from the antenna unit through the radio frequency connector and respectively sends the LTE wireless air interface signal to the LTE uplink receiver and the LTE downlink receiver for signal demodulation; the LTE uplink receiver demodulates LTE uplink L1, L2 and L3; the LTE downlink receiver demodulates LTE downlink L1, L2 and L3;

the control module selects a working frequency band and a working mode, controls the uplink and downlink time sequence of the LTE, and controls the demodulation of the LTE uplink receiver and the LTE downlink receiver;

the communication module is connected with the control module and also sends the demodulation results of the LTE uplink receiver and the LTE downlink receiver to the cloud computing platform through the Internet for data storage, data operation and data presentation;

the cloud computing platform comprises a cloud service module, a cloud computing module and a cloud storage module;

the cloud service module provides cloud service for a user through the Internet, the user can remotely log in by using client software, the user can send a data processing request, and LTE air interface test data are displayed on a screen of the user client in a text or/and graphic mode;

the cloud computing module completes extraction, computation and association of LTE air interface test data, and classifies and sorts the data according to specific requirements of users;

the cloud storage module stores LTE air interface original test data and data after calculation and analysis on the cloud computing platform.

the antenna comprises an antenna unit and a radio frequency connector;

the LTE air interface measuring device comprises an LTE air interface demodulation module, a control module, a communication module and a positioning module;

the positioning module is used for measuring the geographical position information of the LTE air interface measuring device during working and sending the geographical position information to the cloud computing platform through the communication module;

the antenna comprises an antenna unit and a radio frequency connector;

the LTE air interface measuring device comprises an LTE air interface demodulation module, a control module, a communication module, a positioning module and a storage module;

the storage module is used for storing original test data when the LTE air interface measuring device works;

According to the technical scheme provided by the embodiment of the invention, through innovation in software and hardware technologies, the wireless communication condition of the LTE air interface is truly and objectively reflected by simultaneously acquiring and analyzing uplink and downlink signals from the LTE wireless air interface and uniformly processing the uplink and downlink signals on the cloud computing platform, so that the effect of quickly positioning the LTE air interface problem is achieved. Therefore, a novel and convenient LTE air interface monitoring and data analysis system is provided for an LTE mobile network operator.

Drawings

Fig. 1 is a schematic diagram of an LTE conventional drive test system;

fig. 2 is a schematic diagram of an embodiment of a cloud computing system for implementing LTE air interface data analysis according to the present invention;

fig. 3 is a schematic diagram of another embodiment of the cloud computing system for implementing LTE air interface data analysis according to the present invention.

Detailed Description

The embodiment of the invention provides a cloud computing system for realizing LTE air interface data analysis.

In order to make the technical field of the invention better understand the scheme of the invention, the following detailed description of the embodiments of the invention is provided in conjunction with the accompanying drawings and the implementation mode.

In a feasible LTE air interface test system scheme, a traditional drive test system of "drive test software" and "drive test terminal" can be used for troubleshooting, evaluation, optimization and maintenance of an LTE network. The drive test software is Windows or Linux application software running on a computer, supports indoor and outdoor tests of voice dialing, data service, value added service and MOS (metal oxide semiconductor) in a mobile network, supports various network frequency scanners (Scanner) tests, supports a user to self-define test events based on L3 signaling and can self-define icons and sound files for displaying the test events, and realizes sound alarm and geographical display of the events in the test process. The drive test software supports data playback and marking in the test process; the method has a flexible playback function, supports forward and reverse playback and random point playback of the test data, can adjust the playback speed in multiple stages, and all open windows of the same data are kept associated during playback. The drive test terminal mainly refers to a special drive test terminal or some commercial terminals which can be connected with drive test software by opening an engineering mode and can be controlled by the drive test software. For example, common LTE-dedicated drive test terminal manufacturers in the market include: companies such as Sequans France, Qualcomm in the United states, Haesi and Pistasia in China; the commercial terminal which can be controlled by the drive test software comprises: some types of LTE mobile phone terminals produced by mobile phone manufacturers such as Samsung, Huacheng and the like. Fig. 1 shows a schematic diagram of such a conventional drive test system.

From the actual requirement of LTE network optimization, the scheme only supports the acquisition and analysis of downlink signals of the LTE network, and cannot simultaneously observe the uplink and downlink interaction process of LTE air interface signals; in addition, not all LTE commercial terminals support the control of the drive test software, and thus, this solution lacks versatility and convenience.

Fig. 2 is a schematic diagram illustrating an embodiment of a cloud computing system for implementing LTE air interface data analysis according to the present invention, where arrows mainly indicate main flow directions of LTE air interface monitoring data and system control signals in these devices and the cloud computing platform.

As shown in fig. 2, the system comprises an antenna, an LTE air interface measurement device, and a cloud computing platform.

An antenna is a converter which converts a guided wave propagating on a transmission line into an electromagnetic wave propagating in an unbounded medium (usually free space) or vice versa, and is a component for transmitting or receiving an electromagnetic wave in a radio device. Including LTE mobile communications, all that utilizes electromagnetic waves to transmit information relies on antennas to operate. The antennas can be divided into transmitting antennas and receiving antennas according to the operating property, and the antennas are reversible, that is, the same antenna can be used as both the transmitting antenna and the receiving antenna. The directional antennas may be classified into an omni-directional antenna and a directional antenna. The antenna can be classified into a long wave antenna, a medium wave antenna, a short wave antenna, an ultra-short wave antenna, a microwave antenna, etc. according to the operating wavelength. The antenna used in the invention belongs to a receiving antenna because the antenna only carries out LTE air interface monitoring and does not need to send signals; secondly, the LTE can work in dozens of different wireless frequency bands from 700MHz to 3700MHz in the global range, so that a receiving antenna used by the LTE air interface monitoring device can support the frequency bands; finally, the LTE system specifies three types of antenna technologies: MIMO, beamforming and diversity methods, therefore, the LTE receiving antenna used in the present invention may be 1 or multiple (e.g. 4 or 8) antenna units, and an omni-directional antenna or a directional antenna is adopted according to the monitoring requirement. The radio frequency connector of the antenna is used for transmitting the received wireless signals to the LTE air interface measuring device, and the SMA type or N type coaxial connector is commonly used in mobile communication and adopts threaded connection, so that the radio frequency connector has the characteristics of high reliability, strong shock resistance, excellent mechanical and electrical properties and the like. Selecting a proper antenna is very important for improving the robustness of the LTE air interface measuring device and the sensitivity of air interface monitoring.

The LTE air interface measuring device comprises an LTE air interface demodulation module, a control module and a communication module. The LTE air interface demodulation module comprises a radio frequency module, an LTE uplink receiver and an LTE downlink receiver.

The radio frequency module in the LTE air interface demodulation module comprises 1 or more independent radio frequency receiving channels, each channel can realize independent tuning, and parameters such as gain, frequency and the like of each channel can be independently controlled, so that various requirements of LTE air interface monitoring can be met. Each independent radio frequency receiving channel comprises a pre-protection circuit, a band-pass filter, a local oscillator, a mixer, an amplifier, an attenuator and other functional modules, so that the radio frequency module can be protected from being damaged when electrostatic discharge or large signals are input, and the radio frequency module is realized according to the system design requirements of LTE on key technical indexes such as working frequency band, dynamic range, sensitivity, noise coefficient and the like. For example, the sensitivity required by the protocol of the TD-LTE system under the bandwidth of 20MHz is-101.5 dBm, and the radio frequency module in the present invention should not be lower than this standard in design. In addition, in the TD-LTE system, uplink and downlink work in the same frequency band, so the configuration parameters of the working frequency bands of 1 or more radio frequency channels are completely the same; in the FDD LTE system, the uplink and the downlink respectively operate in different frequency bands, and at this time, the radio frequency module should include more than 2 independent radio frequency receiving channels, where not less than 1 radio frequency channel is used for receiving uplink signals, and not less than 1 radio frequency channel is used for receiving downlink signals.

The LTE uplink receiver or the LTE downlink receiver in the LTE air interface demodulation module includes an Analog-to-Digital Converter (a/D Converter or ADC), which samples a band-pass signal or a baseband signal output by the radio frequency module to complete conversion from an Analog signal to a Digital signal. The main technical indexes of the ADC comprise resolution, conversion rate, quantization error, linearity and the like, and a parallel interface or a serial interface is adopted for sample value output. Because the transmission rate of an LTE signal after IFFT operation in 20MHz bandwidth reaches 30.72Mbps, the conversion rate of an ADC in practical application is generally 2-8 times of the transmission rate, namely 61.44-245.76 Mbps, the conversion rate is calculated by 12 bits of resolution, the highest output rate of a single channel can reach 3Gbps, and therefore a differential serial output mode is generally adopted. Major ADC manufacturers in the market at present include ADI, Texas Instrument (TI), Linear (Linear), and Maxim in the united states, and take a device with the model AD6649 of the ADI company as an example, the resolution of the AD6649 is 14bit, the maximum conversion rate supports 250Mbps, and the requirements of the present invention on the ADC performance can be satisfied.

The LTE uplink receiver demodulates LTE uplink L1, L2, and L3. Wherein, L1 is a Physical Layer (Physical Layer), and mainly includes three channels of PRACH, PUCCH, and PUSCH, and respectively handles LTE user uplink random access, uplink signaling control, and uplink data shared transmission; l2 is a media access control layer, which mainly includes MAC, RLC and PDCP sublayers; l3 is the service layer, which mainly includes RRC, NAS signaling sublayer, and IP data layer.

The content of the demodulation output of the LTE uplink receiver mainly includes: the LTE system comprises control information such as the category of an LTE terminal, user identification information, random access, power control, cell reselection, BLER, RB occupation, MCS, scheduling condition, switching process, HARQ, uplink throughput and the like; l2 header information of MAC, RLC, PDCP; RRC and NAS complete signaling; IP packets and traffic data.

The LTE downlink receiver demodulates LTE downlink L1, L2, and L3. Wherein, L1 is a Physical Layer (Physical Layer), which mainly includes channels such as PBCH, PCFICH, PHICH, PDCCH, PDSCH, etc., and respectively handles LTE downlink synchronization and cell search, downlink signaling control, and downlink data sharing transmission; l2 is a media access control layer, which mainly includes MAC, RLC and PDCP sublayers; l3 is the service layer, which mainly includes RRC, NAS signaling sublayer, and IP data layer.

The content of the demodulation output of the LTE downlink receiver mainly includes: network information such as cell ID, working mode, working frequency, bandwidth, special subframe type and the like; service cell information such as RSSI, RSRP, RSRQ, SINR and the like; neighbor cell information; control information such as CQI, PMI, RI, ACK, NACK, BLER, MIMO, RB occupancy, DCI, MCS, HARQ, and downlink throughput; RRC and NAS complete signaling; IP packets and traffic data.

Specifically, the functions of the LTE uplink receiver and the LTE downlink receiver may be realized in a manner of combining software and hardware.

Because the LTE network provides the peak rates of 50Mbps uplink and 100Mbps downlink, the network delay is low, the control plane delay is required to be less than 100ms, and the user plane delay is required to be less than 5 ms; in the demodulation process, not only precise and complex algorithm calculation including matrix inversion and Turbo decoding needs to be performed, but also analysis of control plane messages and interactive control between uplink and downlink need to be completed in time. Therefore, in a specific implementation, an FPGA (Field Programmable Gate Array) and/or a DSP (digital signal processor) device is generally used, and demodulation of L1 (physical layer) or demodulation of part of L2 functions is implemented by programming; and part or all of the L2 function, and the demodulation of L3, are implemented on the CPU of the ARM or PowerPC architecture. In order to improve the operation processing capacity, a multi-core ARM or a multi-core PowerPC is generally used, and a mode that a plurality of CPU cores share a large number of demodulation tasks is adopted. In addition, in order to meet the requirement of low processing delay of L2 and L3, an embedded real-time operating system must be run on an ARM or PowerPC, so that not only is timely response to interrupts from an FPGA and/or a DSP outside a CPU ensured, but also effective task scheduling is ensured when a plurality of CPU cores cooperate. At present, suppliers of the FPGAs in the market mainly include Virtex series of Xilinx and Altera, and stratex series FPGAs of Xilinx and Altera in the united states, which can meet the operation requirement of LTE uplink or downlink L1 demodulation; suppliers of DSP are mainly Texas Instruments (TI) and Freescale (Freescale) in the United states, and both manufacturers have their own multi-core DSP products. In addition, the multi-core PowerPC is used for years in the mobile communication industry and is a common device of an LTE base station product; the multi-core ARM is also gradually widely used in the LTE research and development field due to the characteristics of low power consumption, strong expandability and the like. Embedded real-time operating system suppliers include U.S. WindRiver and sweden ENEA corporation, VxWorks of WindRiver, and OSE embedded real-time operating system of ENEA corporation, which are always the best products in the industry; in addition to VxWorks and OSE, embedded Linux is also an option.

The control module in the LTE air interface demodulation module has the main functions of receiving a control instruction sent by a user through the cloud computing platform through the communication module and controlling the radio frequency module to select the working frequency band of the LTE; and setting the working mode of the LTE air interface measuring device, enabling the LTE air interface measuring device to work in a frequency sweeping mode, a monitoring mode and other states, generating corresponding LTE uplink and downlink time sequences according to the working mode, and respectively controlling the LTE uplink receiver and the LTE downlink receiver to complete demodulation of L1, L2 and L3. In a concrete reality, the radio frequency control is generally directly driven by an FPGA or a DSP; the control of the LTE uplink receiver and the LTE downlink receiver specifically relates to demodulation control of L1, L2, and L3, and requires sequential cooperative operation from an embedded CPU to an FPGA and/or a DSP; from the perspective of an embedded operating system, the control module may be comprised of a set of embedded drivers, each of which performs one or more specific control functions.

The communication module in the LTE air interface demodulation module is used for connecting the control module with the cloud computing platform and also completing the function of transmitting the demodulation results of the LTE uplink receiver and the LTE downlink receiver to the cloud computing platform. The minimum time unit of the data format output here is 1ms, which is also one TTI (or one Subframe) period in LTE. The LTE system takes TTI as a basic unit, and performs uplink or downlink wireless resource scheduling once every 1ms at the fastest speed. Therefore, as an LTE air interface monitoring system and device, control information and user data demodulated in every 1ms need to be completely sent to a cloud computing platform for data storage, data operation and data presentation. The connection between the LTE air interface measuring device and the cloud computing platform can be in a wired mode or a wireless mode. The wired mode may be GbE (gigabit ethernet), and the wireless mode may be WiFi (a standard in IEEE 802.11), 4G, or other high-speed wireless access technologies.

The cloud computing platform can be a private cloud, namely a cloud computing platform built by an enterprise; public clouds such as amazon, google, and chinese arilocos, and cloud computing platforms provided for the whole society may also be rented. In a cloud computing environment, software technology and architecture are changed remarkably. Firstly, developed software must be adaptive to cloud, can be organically combined with a cloud platform virtualized as a core, and is adaptive to dynamic changes of computing capacity and storage capacity; secondly, the use of a large number of users, including data storage structures and processing capacity, is required to be met; thirdly, providing application of software based on the internet by internet; fourthly, the security requirement is higher, can resist attacks, and can protect private information, and fifthly, the mobile terminal can work in various environments such as mobile terminals, mobile phones, network computers and the like. In the cloud computing environment, the environment and the working mode of software development will also change. Although the traditional software engineering theory cannot be fundamentally changed, the development tool, the development environment and the development platform based on the cloud platform bring convenience for agile development, project group collaboration, remote development and the like. The cloud platform can be utilized in the software development project group to realize online development, and the cloud is utilized to realize knowledge accumulation and software reuse. Under the cloud computing environment, the final expression forms of the software products are more abundant and diversified. On the cloud platform, the software may be a service, such as SaaS, or may be Web Services, or may be an application that can be downloaded online.

The cloud computing platform comprises a cloud service module, a cloud computing module and a cloud storage module. The cloud service module mainly solves the problem of human-computer interaction. On one hand, the working mode of the LTE air interface measuring device is set according to the selection of a user, and control information is sent to the LTE air interface measuring device through a communication module so as to start the measuring device and execute the test according to the task set by the user; on the other hand, the air interface monitoring information is displayed on the client screen of the user in a text or/and graphic mode, and the air interface monitoring information can be original test data of the LTE air interface measuring device or processed analysis data.

The cloud computing platform comprises a cloud computing module, completes data extraction, computation and association according to the characteristics of LTE air interface data, and classifies and sorts data according to the content of a user request.

Specifically, the cloud service module and the cloud computing module are cloud application programs on the cloud platform. The specific programming language may be one or more of PHP, ASP, JAVA, and other common programming languages.

The cloud storage module in the cloud computing platform provides mass data storage capacity by integrating a large number of heterogeneous storage devices, and has good expandability and extremely high reliability. The cloud storage module stores LTE air interface original test data and data after calculation and analysis on the cloud computing platform.

In addition, a positioning module can be added in the LTE air interface measuring device and used for recording the geographical position information of the LTE air interface measuring device during working. When analyzing and presenting LTE air interface monitoring data, a user often needs to associate measured technical parameter values with geographical locations to study the wireless coverage condition of an LTE network.

Specifically, the positioning module may be one or more of chinese beidou, american GPS, russian GLONASS, and european union GALILEO satellite positioning devices. The method can realize that the longitude and latitude coordinate values at the time are recorded when the LTE air interface measuring device works.

A positioning module may be added to the LTE air interface measurement apparatus as shown in fig. 3, where an arrow mainly indicates a main signal flow direction when the positioning apparatus interacts with the control module. In addition, the positioning module sends the geographic location information to the cloud computing platform through the communication module.

In addition, the LTE air interface measurement apparatus may further include a storage module. The main function of the storage module is to directly store original test data on an LTE air interface measuring device so as to prevent loss of very important external field test data when connection with an external cloud computing platform is interrupted. Because many air interface problems of the LTE are not easily reproduced, the cost of testing in the field is very high, and the memory module can be used as a standby function to be started when necessary.

As shown in fig. 3, the storage module and the control module are connected to each other, and may be a high-speed storage device such as a Solid State Disk (SSD), a FlashRAM, a Flash memory Card (Flash Card), and the like.

Typical application scenarios of a cloud computing system implemented according to the present invention include, but are not limited to: network optimization of an LTE mobile operator; testing the service performance of an LTE mobile operator; testing a base station of an LTE network equipment manufacturer; and (4) testing the performance of the commercial mobile phone of an LTE mobile terminal manufacturer.

While the embodiments of the present invention have been described by way of example, those skilled in the art will appreciate that there are numerous variations and permutations of the present invention without departing from the spirit of the invention, and it is intended that the appended claims cover such variations and modifications as fall within the true spirit of the invention.

Claims

1. The utility model provides a realize cloud computing system of LTE air interface data analysis which characterized in that, includes antenna, LTE air interface measuring device and cloud computing platform, wherein:

the antenna comprises an antenna unit and a radio frequency connector;

the LTE air interface demodulation module comprises a radio frequency module, an LTE uplink receiver and an LTE downlink receiver; the radio frequency module receives an LTE wireless air interface signal from the antenna unit through the radio frequency connector and respectively sends the LTE wireless air interface signal to the LTE uplink receiver and the LTE downlink receiver for signal demodulation; the LTE uplink receiver demodulates LTE uplink L1, L2 and L3; the LTE downlink receiver demodulates LTE downlink L1, L2 and L3; the L1 is a physical layer, the L2 is a media access control layer, and the L3 is a service layer;

the control module selects a working frequency band and a working mode, generates an LTE uplink and downlink time sequence according to the working mode, and controls the demodulation of the LTE uplink receiver and the LTE downlink receiver;

2. The utility model provides a realize cloud computing system of LTE air interface data analysis which characterized in that, includes antenna, LTE air interface measuring device and cloud computing platform, wherein:

the antenna comprises an antenna unit and a radio frequency connector;

3. The utility model provides a realize cloud computing system of LTE air interface data analysis which characterized in that, includes antenna, LTE air interface measuring device and cloud computing platform, wherein:

the antenna comprises an antenna unit and a radio frequency connector;