Residential Area Construction and Application of Broadband Wireless Access System

In the previous article, we introduced the concept of Dual-Layer Broadband Wireless Access Network. Next we will give a detailed introduction to the broadband wireless access system used by the macro community network. The broadband wireless access system is the main application technology of the residential network.

Macro Community Network

According to the current frequency distribution in China, the LMDS low frequency (3.5 GHz) network is used as the high-speed core network in the macro community, AN03W-X035 LMDS system with WRI (this system can be smoothly upgraded to 2 GHz ~ 40 GHz ). This system is a point-to-multiple-point Broadband Wireless Access System Based on IP addresses. It adopts the TDM/TDMA multi-access mode and supports bidirectional speech, Data, video images, and circuit services. The core part of the system is composed of wireless base station equipment (WMTS), wireless client equipment (WMU) and network management system (NMS.

A typical GHz broadband wireless access system consists of multiple base stations, hundreds of user-side devices, and a unified network management system. In order to improve the spectrum utilization of the gold GHz band and expand the system capacity, the macro-cell adopts sector segmentation (optional sector angle), band refinement, and same-frequency multiplexing. Dynamic Power Control, antenna polarization, and frequency planning are used to overcome interference between different base stations and sectors. Optional values: 7 MHz, 3.5 MHz, and 1.75MHz. Optional values: 3.2 MHz, 1.6 MHz, 800 KHz, 400 KHz, and KHz.

The broadband wireless access system adopts the docsis enhanced standard (provided by VYYO), which is improved and ENHANCED in the DOCSIS standard of the Cable Modem industry to apply to wireless environments. DOCSIS standards are well defined in terms of network and data connection protocols, QOS, coverage areas, synchronization, registration, encryption, and confidentiality. However, because the DOCSIS standard is designed for cable TV (CATV) systems, it is insufficient to overcome some unique problems in the wireless environment, such as frequency offset, dynamic range, stray emission, multi-Longitude effect and fading. WRI enables stable and efficient system operation in the full-band (including registered or unregistered) by enhancing the DOCSIS standard. The enhancement content mainly includes: Multiple modulation modes, three modulation modes are adopted: downlink PSK, 16QAM, and 64QAM, and two types are supported: uplink PSK and 16QAM; compensate for the offset and drift frequency generated with temperature and aging, low stray emission and Intermodulation Interference, extended dynamic range, and improved power control. Some of the enhancements above make the AN03W-X035 system fully compliant with national standards and provide robust performance in RF channels.

WRI AN03W-X035 network management system is a kind of customer/server system, based on SNMP Network industrial standard, applied to WindowsNT4.0/2000 platform. System operators can monitor and control all WMTS and WMU in the network through the Network Manager. The main functions include polling status, downloading software, system configuration, traffic statistics, alarm support, and monitoring. The network management system is flexible and operable. It can monitor and control devices in any network at any physical address. The network structure of the macro community is shown in figure 2.