The IEEE802.11b standard was designed to be compatible with the existing IEEE802.11 standard, but this one was standardized using the latest technology at the time without being bound by compatibility.
The radio frequency uses the 5GHz band, and the theoretical maximum transmission speed is 54Mbps. If you use it only in the room, the radio waves are easy to reach and you can use it stably, but if you are in different rooms or on different floors, the radio waves are difficult to reach and the exchange of data becomes unstable.
The center frequency of the channel used for IEEE802.11a has become an international standard, replacing the 4-channel allocation of J52 (5.15 to 5.25 GHz) used in Japan due to the revision of the ministerial ordinance in May 2005. W52 and W53 use 5.15 to 5.35 GHz because the W52 has 4 channels and the new W53 has 4 channels.
This makes a total of 8 channels available.
In January 2007, an amendment to the ministerial ordinance added 11 W56 channels that can be used outdoors, bringing the total number of channels to 19.
This added channel is also available outdoors.
In this way, IEEE802.11a has changed the channel allocation, so even if you are using products that support IEEE802.11a, there may be cases where devices manufactured at different times cannot be connected. I have.
The appeal of IEEE802.11a is that it can be used outdoors and has a large number of available channels.
As a result of rearranging and adding channels, IEEE802.11a currently has 19 channels available.
As shown above, all 19 channels can be used simultaneously because there is no overlap between channels.
Outdoor use of IEEE802.11a
IEEE802.11a was amended in January 2007 by ministerial ordinance, adding 11 channels of W56 that can be used outdoors, bringing the total number of channels to 19.
This added channel can be used outdoors.
Not all channels available in IEEE802.11a are available outdoors. Please note that outdoor use of IEEE802.11a (5.2GHz, 5.3GHz) is prohibited by the Radio Law.
With the release of the 5.6GHz band (W56), wireless LAN can now be used outdoors under the IEEE802.11a standard, so outdoor antennas that can be used outdoors are on the market.
W56 is a newly opened band, so there is little possibility of receiving radio wave interference, and stable outdoor communication can be performed. Mounting brackets for outdoor antennas are also available for easy installation.
- Building independent installation type
- Veranda installation type
- Veranda installation simple type
etc., are on sale.