Commercial Availability of Smart Antennas Hệ thống ăng-ten thông minh được thiết kế để làm giảm căng thẳng khả năng trong các trang web di động kinh nghiệm phân phối giao thông nặng và mất cân bằng. Kể từ khi giao thông có xu hướng thay đổi đáng kể trong vòng một mạng, một trang web di động cá nhân và theo thời gian, nó là rất quan trọng cho các nhà cung cấp dịch vụ không dây để phân bổ hiệu quả các nguồn tài nguyên cơ sở hạ tầng và phổ để đáp ứng năng lực mạng lưới. | 149 CHAPTER 9 Commercial Availability of Smart Antennas Smart antenna systems are designed to relieve capacity strain in cell sites experiencing heavy and imbalanced traffic distribution. Since traffic tends to vary considerably within a network at an individual cell site and over time it is critical for wireless service providers to allocate efficiently infrastructure and spectrum resources to meet network capacity and performance demands. Although smart antennas date back since the late 1950s it is only because of today s advancement in powerful low-cost digital signal processors general-purpose processors and ASICs - Application Specific Integrated Circuits as well as innovative software-based signal processing techniques algorithms that smart antenna systems are gradually becoming commercially available. Several papers and studies in the area have been published in the recent years and a growing number of companies are studying MIMO systems for future use. Several companies have been created recently that are trying to commercialize MIMO systems and a number of larger companies are also studying this area. In 94 the author well clarifies the main reasons which explain why smart antenna-enabled systems have not yet been deployed more widely. These are repeated here verbatim as stated in 94 DSP and CPU speeds need to be fast enough to handle the increased computations needed for smart antenna algorithms to be able to be implemented in realtime. This was a big problem until 1999 or so particularly for low-cost solutions. However computing power has now progressed to the point where smart antenna systems can feasibly be installed using inexpensive processors. The value proposition provided by smart antenna systems needs to outweigh the additional cost of a smart antenna system. In the early days of advanced mobile phone systems one base station could cover a large area and there was no need for multiplying the capacity of a base station. Today when microcells and .
