Omron and Wireless LAN

This Technical Note is aimed at giving an overview of Omron's wireless LAN capabilities and interactions.
A wireless LAN or WLAN is a wireless local area network, which is the linking of two or more computers or PLCs without
using wires. WLAN utilizes spread-spectrum modulation technology based on radio waves to enable communication
between devices in a limited area, also known as the basic service set. This gives users the mobility to move around
within a broad coverage area and still be connected to the network.
Omron introduced WLAN Access Point (WE70AP)and WLAN Client (WE70CL).

The WE70 products conform with IEEE 802.11 a/b/g, supports WEP RC4 and OCB AES encryption, TKIP, AES, and WOC KEY (Omron Security). The smart roaming function enables highspeed roaming therefore moving equipment and mobile objects can communicate at high speed.

Spectrum assignments and operational limitations are not consistent worldwide. Most of Europe allows for additional channels beyond those permitted in the U.S for the 2GHz band. (1-13 vs.1-11);Japan has one more on top of that (1-14).

WiFi signal occupies five channels in the 2.4GHz resulting in only 3 non-overlapped channels in the US: 1,6,11.

24GHz channels

WLAN, or an excessive number of access points in the area, especially on the same or neighboring channel, can prevent access and interfere with the use of other access points by others, caused by overlapping channels in the 802.11g/b spectrum. This can be a problem in high-density areas, such as large apartment complexes or office buildings with many WiFi access points.

The typical range of a common 802.11g network with standard equipment is in the order of tens of meters. While sufficient for a typical home, it will be insufficient in a larger structure. To obtain additional range, repeaters or additional access points will have to be purchased.

Additionally, other devices using the 2.4GHz band: microwave ovens, cordless phones, baby monitors, security cameras, and Bluetooth devices can cause significant additional interference. General guidance to those who suffer these forms of interference or network crowding is to migrate to a WiFi 5GHz product (802.11a) usually a dual band product as the 5GHz band is relatively unused and there are many more channels available. This also requires users to set up the 5GHz band to be the preferred network in the client and to configure each network band to a different name (SSID).

5GHz channel
In addition to the pencil type antenna provided as standard, magnet antenna and flat diversity antenna are now available as options. For the magnet antenna the main body can be installed in the panel and the antenna outside the panel. An antenna suitable for installation sites can be selected. TheWE70 family is developed for the industrial environment (noise and environment resistance at industrial levels equivalent with PLC). Specific models for use in USA, Europe and China are available.