Some Wireless Network Specifications
Here we will learn some technology specifications that can be used as a base reference in the development of network infrastructure without wires, whether indoor or outdoor, even MAN.
A. Fixed Wireless
is a wireless technology where the sender and receiver occupy a fixed location such as home or office. Applying this technology is MMDS (Multichannel Multipoint Distribution Service), LMDS (Local Multipoint Distribution Services), Point-to-Point Microwave, or WLAN.
A.1 MMDS (Multichannel Multipoint Distribution Service)
operate in the spectrum of 2.5 - 2.7 GHz with a width of 200 MHz. Throughput which can be given is 1-2 Mbps. The distance that can be taken is 35 mile from the radio port controller (RPC) which is based on the strength of signal.
A.2 LMDS (Local Multipoint Distribution Services)
a microwave communication systems with models of point-to-multipoint who works on a frequency of 20 GHz. Bandwidth provided to 500 Mbps. Typically used for short distances that require bandwidth high, such as campuses, companies, etc..
Example:
A.3 Point-to-point microwave
is a technology line-of-sight is very influenced by multipath and the absorption of some other object, such as MMDS and LMDS
A.4 Wireless LAN
Connection type Wireless LAN
● W-LAN Outdoor - used for connecting devices in the outdoors, follow the 802.16 standard
● W-LAN Indoor - used for connecting devices in the indoors, follow the 802.11 standard
Use of wireless technology for local networks, can follow standardization of IEEE 802.11x, where x is a sub standard which consists of:
• 802.11 - 2.4 GHz speed up to 2Mbps
• 802.11a - 5GHz speeds up to 54Mbps
• 802.11a 2X - 5GHz speeds up to 108Mbps
• 802.11b - 2.4 GHz speeds up to 11Mbps
• 802.11g - 2.4 GHz speeds up to 22Mbps
• 802.11n - 2.4 GHz speeds up to 120Mbps
802.11 MAC is known DFWMAC (distributed foundation wireless MAC). Flowchart of the algorithm is:
Here are the types of W-LAN devices
Examples of W-LAN device specifications
● Output Power
• 5150 ~ 5700 GHz
15 dBm (+ / - 2 dB) for 6 Mbps
12 dBm (+ / - 2 dB) for 54 Mbps
• 5745 ~ 5850 GHz
15 dBm (+ / - 2 dB) for 6 Mbps
10 dBm (+ / - 2 dB) for 54 Mbps
● Antenna Gain
2.81dBi Max.
● Receiver Sensitivity
Min. -67dBm for 54 Mbps @ 10% PER
Min. -73dBm for 36 Mbps @ 10% PER
● Power Consumption
520 mA at transmit mode
310 mA at receive mode
Use of specification 802.16 (wireless broadband) to the network outdoor is very expensive, so there is no harm if we also using the 802.11 specification for these outdoor networks. There a few things to note:
● Radio 802.11b only has 11 channels
● The installation must follow the rules of Line of Sight
● Requires the tower if two points are at different levels
● Use a small power should really be taken into account
● Must overcome the interference that occurs Using the PCMCIA in the computer
Using the Access Point to connect to external antenna
802.11 is used in indoor known as the HotSpot and standards WiFi
● One access point can not serve more than 50 clients
● Installation of access points should not interfere with each other frequencies (Remember: there are only 3 frequencies are not mutually stacked)
No comments:
Post a Comment