摘要
游牧和移动宽带无线接入将成为未来通信市场的重要需求。WiMAX正是针对这一需求而专门发展的,其性能强、效率高、成本低,具有灵活的体制,可通过配置满足各种应用场景的要求。同样,为了进入宽带无线接入市场,3GPP首先发展了被称为3.5G的HSDPA技术(可以大幅度提高分组数据的传输速率),2004年底又决定发展长期演进(LTE)计划,其指标和技术都与WiMAX相近,可以说是殊途同归。面对LTE的竞争,WiMAX要想在宽带无线接入市场中占有一席之地必须拥有好的频率,使用地面电视广播频率可提供大面积覆盖,降低成本。
Nomadic/mobile broadband wireless access will be the main stream of market in the future. WiMAX (IEEE802.16d/e) was designed to meet the requirement of broadband wireless access specially. It's key technologies include: burst packet data fast scheduling in time frequency domain (OFDMA), advanced modulation and coding (AMC), hybrid automatic repeat request (H-ARQ), multiple-input-multiple-output (MIMO) diversity, enhanced advanced antenna systems (AAS). 3G was designed according to voice service with fixed bandwidth channel, it has very poor performance for burst data. 3GPP develop HSDPA, HSUPA (EV-DO, EV-DV) and then 3GPP LTE by using same technology to increase data rate meet the requirement of broadband wireless access. That means WiMAX and 3G reach the same goal by different routes. Facing the competition from 3GPP LTE, if WiMAX want to get market share of broadband wireless access, have to get good frequency band to increase coverage area and decrease cost. The UHF/VHF TV frequency may be best choice.
出处
《电信科学》
北大核心
2005年第10期18-21,共4页
Telecommunications Science