As mobility skyrockets, every device can get a smoothest internet connectivity with a Wireless LAN (WLAN) whether there is a need of 150-Mbps speeds or more for a power-hungry ERP or CAD application, or only 11 Mbps suffices for simple e-mail. Users can access Internet from WLAN hotspots in restaurants, commercial complexes and schools with portable devices such as laptops, tablets and PDAs.
Two key elements, Wireless LAN Controllers (WLCs) and Access Points (APs), form the core of the WLAN system, where the APs (often called Wi-Fi access points) provide the radio connection between wireless clients and the network, and the WLCs provide network managers provision to configure the WLAN according to business requirements. WLANs have gained popularity due to ease of installation and use, much faster speeds than some other technologies such as GPRS, EDGE and even UMTS and HSDPA, minimized need for traditional wired connections with use of radio or infrared signals, and good range (30 to 100 meters indoors and about 650 meters outdoors).
Deploying a WLAN is no easy task. First, you must do a survey of the wireless site with the placement of all access points to ensure good performance of WLAN. There are portable hardware and software tools that give a detailed view of coverage areas at different sites and help in deployment, management, and controlling some aspects of a wireless network.
An important factor to improve performance in WLAN is throughput planning. A WLAN should contain enough access points to cater to the network speeds of users at which they need to connect and cover all the users which may move away from their access points leading to reduced speeds. Some speed hungry applications may require 54-Mbps speeds of 802.11a and 802.11g, while a simple web browsing application will only need 802.11b’s 11 Mbps, though more recent standards 802.11n and Wi-Fi ac offer even higher speeds up to 150Mbps and 500 Mbps per channel respectively. Further, to meet increasing future demands, a WLAN using 802.11a should be upgradable to 11b. Another point to be kept in mind is that WLAN being a shared medium unlike Ethernet divides speeds among all connected users rather than providing them dedicated speeds.
Security is the second important aspect for WLAN design. Some security solutions such as WEP restrict random wireless clients from joining the WLAN. Many of them incur data overheads with their authentication methods. Data leakage can also be restricted simply by limiting their power outputs and proper antenna orientation.
Mentioned below are some high-performance and cost-effective WLAN reference designs along with complete documentation such as BOM, schematics and user guides:-
- Low-cost WLAN Design: This reference design is a complete high performance RF front-end solution designed to meet the WLAN IEEE 802.11b/g standard in a small PCB form-factor. Using the MAX2830 RF transceiver eliminates the need for external SAW filters, a RF switch, and a PA. Only a RF filter, RF balun, and a small number of passive components are required to form a complete 11b/g WLAN RF front-end solution. Using the MAX2830 RF transceiver, the design is capable of accommodating full range of 802.11g OFDM data rates and 802.11b QPSK data rates. This solution offers high performance, small size, and low BOM cost. More on this Reference Design
- WLAN Access Point with Security: Here is a reference design that supports applications of Wi-Fi Router, DMS (Digital Media Server), NAS with RAID, or Office in BOX, etc. The design is based on the MPC8377E PowerQUICC Pro processor. The design features integrated hardware acceleration for wireless security, MiniPCI or MiniPCI Express based interfaces for 802.11N radio modules, gigabit Ethernet LAN and WAN interfaces, USB 2.0 host/device interface and support for dual-concurrent MIMO operation. The design comes equipped with schematics, Gerber files, reference software, Bill Of Material (BOM) which can help original equipment manufacturers (OEMs) and original design manufacturers (ODMs) accelerate the development process and speed time-to-market for their real product. More on this Reference Design
- Compact RF Wireless Module: This reference design is a cost-effective and small-footprint (1.61″ by 1.02″) wireless radio system that can be designed into any number of monitoring and control applications to enable wireless control. It is available in both the 868 MHz and 915 MHz radio frequency bands. The Module can be easily mounted on a two-layer PCB with minimal external connections. This document discusses its specifications, lists schematics and software commands, and provides a procedure for quickly getting started with development. More on this Reference Design