680896
13
Zoom out
Zoom in
Previous page
1/97
Next page
LANCOM L-32x Access Point series
Chapter 1: Introduction
12
EN
Modulation of digital data into analog carrier signals
Modulation of the carrier signal into a radio signal in the selected fre-
quency band, which for a wireless LAN is either 2.4 or 5 GHz.
The second modulation step in IEEE 802.11n occurs in the same way as in
conventional wireless LAN standards and is therefore not covered here.
However, there are a number of changes in the way digital data are modula-
ted into analog signals in 802.11n.
Improved OFDM modulation (MIMO-OFDM)
Like 802.11a/g, 802.11n uses the OFDM scheme (Orthogonal Frequency Divi-
sion Multiplex) as its method of modulation. This modulates the data signal
not on just one carrier signal but in parallel over several. The data throughput
that can be achieved with OFDM modulation depends on the following para-
meters, among other things:
Number of carrier signals: Whereas 802.11a/g uses 48 carrier signals,
802.11n can use a maximum of 52.
Payload data rate: Airborne data transmission is fundamentally unreli-
able. Even small glitches in the WLAN system can result in errors in data
transmission. Check sums are used to compensate for these errors, but
these take up a part of the available bandwidth. The payload data rate
indicates the ratio between theoretically available bandwidth and actual
payload. 802.11a/g can operate at payload rates of 1/2 or 3/4 while
802.11n can use up to 5/6 of the theoretically available bandwidth for
payload data.
20 MHz 20 MHz
IEEE 802.11a/b/g:
48 carrier signals
IEEE 802.11n:
52 carrier signals
13


Need help? Post your question in this forum.

Forumrules


Report abuse

Libble takes abuse of its services very seriously. We're committed to dealing with such abuse according to the laws in your country of residence. When you submit a report, we'll investigate it and take the appropriate action. We'll get back to you only if we require additional details or have more information to share.

Product:

For example, Anti-Semitic content, racist content, or material that could result in a violent physical act.

For example, a credit card number, a personal identification number, or an unlisted home address. Note that email addresses and full names are not considered private information.

Forumrules

To achieve meaningful questions, we apply the following rules:

Register

Register getting emails for Lancom L-321agn Wireless at:


You will receive an email to register for one or both of the options.


Get your user manual by e-mail

Enter your email address to receive the manual of Lancom L-321agn Wireless in the language / languages: English as an attachment in your email.

The manual is 1,57 mb in size.

 

You will receive the manual in your email within minutes. If you have not received an email, then probably have entered the wrong email address or your mailbox is too full. In addition, it may be that your ISP may have a maximum size for emails to receive.

The manual is sent by email. Check your email

If you have not received an email with the manual within fifteen minutes, it may be that you have a entered a wrong email address or that your ISP has set a maximum size to receive email that is smaller than the size of the manual.

The email address you have provided is not correct.

Please check the email address and correct it.

Your question is posted on this page

Would you like to receive an email when new answers and questions are posted? Please enter your email address.



Info