802.11a,g channels

hi,
can anybody answer me:
g)what is the size of 1 channel in 802.11g and where are the centers of this
channels? and how many channels has 802.11g standard specified in allowed
bandwidth (2.4000 - 2.4835).how many channels are independent (transmissions
without disturbing each other)
a)where can i find informations about channels and bandwidth used in 802.11a
standard. In standard there are informations only about channels in usa (8
independent channels in lower unii bands and 4 in higher unii band). i'm
intrested in european regulations. I know that there are 2 bandwidth
allowed: 5150-5350MHz and 5470-5725MHz but how many channels can be used in
them? (in 5150-5350 i guess it is 8 channels)

thx
michal

the answer is called DO A SEARCH - google.com etc idle twat


"mikez" <(E-Mail Removed)> wrote in message
news:boo53c$aor$(E-Mail Removed)...
> hi,
> can anybody answer me:
> g)what is the size of 1 channel in 802.11g and where are the centers of
this
> channels? and how many channels has 802.11g standard specified in allowed
> bandwidth (2.4000 - 2.4835).how many channels are independent
(transmissions
> without disturbing each other)
> a)where can i find informations about channels and bandwidth used in
802.11a
> standard. In standard there are informations only about channels in usa (8
> independent channels in lower unii bands and 4 in higher unii band). i'm
> intrested in european regulations. I know that there are 2 bandwidth
> allowed: 5150-5350MHz and 5470-5725MHz but how many channels can be used
in
> them? (in 5150-5350 i guess it is 8 channels)
>
> thx
> michal
>
>
>

U¿ytkownik "383" <(E-Mail Removed)> napisa³ w wiadomo¶ci
news:boo656$o0p$(E-Mail Removed)...
> the answer is called DO A SEARCH - google.com etc idle twat

thank you for help

michal

Michael, you can answer all your channel-related questions by getting the
actual 802.11 standards. They are available for free from IEEE 6 months
after they are published. Goto:

http://standards.ieee.org/getieee802/

802.11g was finalized in June and is not available free yet, but it uses the
same channel layout as 802.11b. Look for table 105 in IEEE Std 802.11b-1999.
You can also get 802.11a for free.

B and G channels are 25Mhz wide, and you can't get more than three
completely non-overlapping cells. In the U.S., the only choices for
nonoverlap are 1, 6, and 11. In ETSI countries channels 12 and 13 are also
used, so in theory you have six different sets of three nonoverlap channels.
France and Spain have much more restricted frequency choices (10-13 and
10-11, respectively) so all cells overlap in these countries.

"mikez" <(E-Mail Removed)> wrote in message
news:boo53c$aor$(E-Mail Removed)...
> hi,
> can anybody answer me:
> g)what is the size of 1 channel in 802.11g and where are the centers of
this
> channels? and how many channels has 802.11g standard specified in allowed
> bandwidth (2.4000 - 2.4835).how many channels are independent
(transmissions
> without disturbing each other)
> a)where can i find informations about channels and bandwidth used in
802.11a
> standard. In standard there are informations only about channels in usa (8
> independent channels in lower unii bands and 4 in higher unii band). i'm
> intrested in european regulations. I know that there are 2 bandwidth
> allowed: 5150-5350MHz and 5470-5725MHz but how many channels can be used
in
> them? (in 5150-5350 i guess it is 8 channels)
>
> thx
> michal
>
>
>

> B and G channels are 25Mhz wide, and you can't get more than three
> completely non-overlapping cells. In the U.S., the only choices for
> nonoverlap are 1, 6, and 11.

B channels are 5MHz wide but one should use 25MHz space to avoid
interferences
unfortunately I cannot find anywhere detailed informations about g
standard(as you have written standard is not available for free yet, i found
some informations but only about draft versions of standard). in particular
i cannot find information about g channel (that is what i really need now).

michal

Here is a spectral plot of b and g signals. Scale is 10 MHz per division.
http://www.corridor.biz/wpc54g.gif

n6gn

mikez wrote:
>>B and G channels are 25Mhz wide, and you can't get more than three
>>completely non-overlapping cells. In the U.S., the only choices for
>>nonoverlap are 1, 6, and 11.
>
>
> B channels are 5MHz wide but one should use 25MHz space to avoid
> interferences
> unfortunately I cannot find anywhere detailed informations about g
> standard(as you have written standard is not available for free yet, i found
> some informations but only about draft versions of standard). in particular
> i cannot find information about g channel (that is what i really need now).
>
> michal
>
>

In article <boqq3j$2o1s$(E-Mail Removed)>, (E-Mail Removed)
says...
> > B and G channels are 25Mhz wide, and you can't get more than three
> > completely non-overlapping cells. In the U.S., the only choices for
> > nonoverlap are 1, 6, and 11.
>
> B channels are 5MHz wide but one should use 25MHz space to avoid
> interferences

802.11b channels are 22MHz wide. Please refer to the 802.11b
specification.

Leszek

Channel *center* frequencies are 5Mhz apart. At the bottom of table 105 in
the B standard, you will see it says that channel centers for
non-overlapping networks must be 25Mhz apart to avoid inteference. Most of
the energy in B signals is spread over 22 Mhz within that range. The
standard does not say how wide the channels are - it's kind of irrelevant.
You can think of it as 14 5Mhz channels which are aggregated together five
at a time for each network cell, or you can think of it as 14 overlapping
25Mhz channels. I prefer the second approach, and I think it's what the
standard actually intends. Either way of thinking models the behavior
correctly.

802.11g uses exactly the same coding techniques as 802.11a (OFDM). 802.11g
clause 19.5.4 says that the 802.11a transmit pulse mask is to be used.
802.11g clause 19.4.2 says that channel numbering and layout follow table
105 in clause 18.4.6.2 of the B standard. In other words, you only need to
look at table 105.

This was done because B and G networks must be able to interoperate. If G
transmitted on a different set of frequencies than B, they would wipe each
other out due to interference.

"mikez" <(E-Mail Removed)> wrote in message
news:boqq3j$2o1s$(E-Mail Removed)...
> > B and G channels are 25Mhz wide, and you can't get more than three
> > completely non-overlapping cells. In the U.S., the only choices for
> > nonoverlap are 1, 6, and 11.
>
> B channels are 5MHz wide but one should use 25MHz space to avoid
> interferences
> unfortunately I cannot find anywhere detailed informations about g
> standard(as you have written standard is not available for free yet, i
found
> some informations but only about draft versions of standard). in
particular
> i cannot find information about g channel (that is what i really need
now).
>
> michal
>
>