Network Swapping

NSW_IMThis topic describes the general principles of network swapping planning, preparations for and implementation of network swapping, principles of coverage planning and cell parameter planning, and acceptance after network swapping.

Network swapping involves equipment from different manufacturers. The difference in the characteristics of the equipment, network structure, quality of construction during swapping, interoperability of the equipment from different manufacturers and optimization level of the swapping project can affect the network performance of the equipment in the same topography. Therefore, GSM network swapping is considered to be complex system engineering. General Principles of Network Swapping Planning.

The prerequisite for network swapping is that the coverage quality should be higher than that of the original network. Network coverage includes the BTS characteristics, site type configuration, combiner performance, and combination mode. Before network swapping, make preparations and set down plans. After network swapping, perform acceptance.

Preparations for Network Swapping

Preparations for network swapping are as follows:

• Information collection: Collect the information about the BTS type, BTS configuration, combination mode, BTS location, antenna system, radio networking parameters, and performance counters.

• Coverage test: Before network swapping, perform the drive test (DT) in the areas where the network coverage is important.

After swapping, perform the DT along the previous route and compare the test results. The purpose of performing the coverage test before network swapping is to fully understand the original network coverage, to test the original network performance, to set down specific network swapping scheme, and to collect the basic data for the entire swapping.

Implementation of Network Swapping

Based on the impact on the network, network swapping can be categorized into the following types:

• Once-and-for-all swapping

• Regional swapping

• Segmental swapping

In terms of the swapping complexity and network quality control, the three swapping strategies have the following features:

• He once-and-for-all swapping is the most advantageous but has the highest requirements, highest influence on the network, and highest risk.

• Regional swapping is moderately complex in terms of network swapping and network quality control, and thus is commonly used.

• Segmental swapping is the most complex network swapping. The network quality control of segmental swapping is difficult because it requires a high engineering quantity and complex Interco operation between manufacturers.

Principles of Coverage Planning

With the same topography and frequency band, radio network coverage may differ because it depends on the BTS hardware characteristics, combination mode, and antenna system configuration.

To maintain the performance of the network coverage, compare the BTS coverage capability before and after swapping.

• Comparing uplink coverage capability: Compare the reference sensitivity of BTSs from different manufacturers and improve the uplink sensitivity using the TMA and the receive diversity technique.

• Comparing downlink coverage capability: Compare the cabinet-top power of BTSs in different configurations and from different manufacturers. Also compare the configuration strategies provided for maintaining the coverage area.

Principles of Cell Parameter Planning

The principles of cell parameter planning are as follows:

• Frequency planning: Check the available frequency resources before and after swapping. Evaluate the frequency planning of the original network through the DT test and the interference traffic statistic counters.

– If the site configuration changes slightly, you need only to modify the original frequency planning.

– If the site configuration changes significantly, or the frequency resources need to be reallocated, or the original frequency planning is not satisfactory, you need to perform a new frequency planning.

• Handover and power control planning: You can make some adjustment in the original neighbor cell relations and then use the adjusted relations. Set the handover algorithm and handover parameters based on the original handover algorithm and handover parameters.

To avoid great changes in handover behaviors after swapping, use algorithms that are of comparatively slight difference.

• Location area planning: The MSC independent networking requires new location areas. In other cases, new location area planning depends on the number of BTSs. When perform new location area planning, consider the paging strategy, location update, SDCCH setting on the edge of the location area, BSC signaling links, and CPU usage.

Acceptance after Networks Swapping

The acceptance after network swapping consists of the DT test, traffic statistics analysis, alarm analysis, and user complaint analysis. Compare the results of the tests performed before and after swapping to know the changes in network quality.