Innovative, Integrated and Effective MR Data Optimization

Since firstly appeared in the 1990s, GSM has been growing for 20 years. As it is becoming more and more mature and robust, its network optimization methods keep evolving from drive test data analysis to signaling trace analysis, counter-based performance data analysis, and to handset-based Measurement Report (MR) data analysis. The optimization methods tend to be more intelligent, diversified and more concerned about user speech perception. In particular, the appearance of MR data optimization has greatly changed the traditional way of network optimization, for it can optimize network performance for each user by acquiring and analyzing key MR data in the call. With a complete analysis from the macro analysis at the network level to the micro analysis at the user level, the MR data optimization is adopted to decode the private “call password” of each user, making it possible to offer user-oriented optimization and enhance user speech perception.

Innovative Data Acquisition

As we all know, under the GSM mode, the mobile phone makes a measurement report every 480ms on the uplink and downlink level/quality/Time Advance (TA), power, and neighboring cell level during the call, which accurately describes the user’s wireless signal environment. However, because of the huge number of users, the daily call measurement reports contain massive data. To acquire and analyze the massive MR data, a higher requirement has been raised on system architecture and the way of data acquisition.

Different from the hard data acquisition mode commonly adopted by equipment manufacturers like Ericsson, Nokia Siemens Networks, and Nortel Networks, where MR data are acquired by hanging a meter on the Digital Distribution Frame (DDF) that connects BSC and BTS, ZTE adopts its innovative soft data acquisition mode (see Figure 1), in which MR data are acquired directly from BSC and used for the dedicated server. The direct MR data acquisition from BSC allows simple networking and easy deployment, making it possible to acquire MR data from multiple equipment rooms and adjust the home location of BTS without any effect on MR data acquisition. As a result, the efficiency and stability of data acquisition has been greatly improved.

Integrated Basic Data

Acquiring all users’ measurement reports cannot fully satisfy the need of network optimization analysis. We are more concerned about in which call events the users make their measurement reports, namely, about the wireless signal environment during the key call events, such as mobile phone access, assignment, handover, and disconnection. As these data are not carried in the measurement reports, they must be provided with the help of BSC. Through the integrated data analysis, an in-depth analysis of each user’s CDR, and the simulation of each user’s wireless environment during the call, we can get the most accurate first-hand information for network optimization and adjustment.

To make basic data as informative as possible, ZTE’s BSC system provides key information about connection point and time for key call events during each user’s call, and gives a detailed explanation for event failure or abnormal connection release. Moreover, the analysis software can simulate the location where the call is made through a special location algorithm to recover to some extent the whole call process. As a result, all users in the network can provide their “drive test reports” 24 hours every day. The perfect integration of the data from BSC and the MR data from the mobile phone provides a basis for analyzing user call behavior and simulating user speech perception, thus making network optimization more accurate and efficient. 

Efficient Network Analysis

ZTE developed its NETMAX, a professional network optimization tool that helps to make all kinds of efficient network analysis.

It can acquire relational data of all cells and their related cells through the automatic full-band BCCH allocation scheduling and use them as the basic data to implement network-wide frequency optimization and neighboring cell optimization. All this helps to reduce interference, lower call-drop rate, improve wireless access rate and handoff success rate, and finally achieve the whole network optimization.

It can acquire MR data of the whole network, and provide uplink and downlink coverage statistics, quality statistics, interference statistics, and traffic distribution statistics. With the fine granularity for statistics that covers the carriers of each Network Element (NE), it can accurately tell apart over-coverage, weak coverage, and interfered cells and areas, providing a basis for adjustment of antenna feeder and frequency band.

It can make relational quality/level/TA analysis (see Figure 2) on the basis of the massive statistical data to find the hidden failure and the cells or carriers. Moreover, through the user access failure or assignment failure, it can find the fault connection boards without dial testing, thus enabling quick and efficient trouble shooting.

It can make a statistical analysis of the terminal capability for all users to find the terminal models that have common problems, and thus implement a real end-to-end network optimization.    

It can analyze user call behavior (such as frequency offset and handoff), simulate user call behavior, optimize wireless parameters of a single cell, and adjust the Location Area Code (LAC) to provide professional and customized network optimization service.

ZTE focuses on decoding and analyzing the private “call password” of each user with its special MR optimization tool, with the view of offering more considerate and professional network optimization service to operators and best service experience to each subscriber.