summaryrefslogtreecommitdiff
path: root/chapter07
diff options
context:
space:
mode:
authorPhilipp Le <philipp-le-prviat@freenet.de>2020-06-30 17:06:54 +0200
committerPhilipp Le <philipp-le-prviat@freenet.de>2021-03-04 22:44:39 +0100
commitc1db4510292b388c228d8d8dab18c6d09cc869ba (patch)
tree9a94765f384bff98d71fd490336783be6b5e6503 /chapter07
parentb0307201182f7222402b8d767fd851ce5b9434fd (diff)
downloaddcs-lecture-notes-c1db4510292b388c228d8d8dab18c6d09cc869ba.zip
dcs-lecture-notes-c1db4510292b388c228d8d8dab18c6d09cc869ba.tar.gz
dcs-lecture-notes-c1db4510292b388c228d8d8dab18c6d09cc869ba.tar.bz2
Note on relation of number of users and OVSF code length
Diffstat (limited to 'chapter07')
-rw-r--r--chapter07/content_ch07.tex14
1 files changed, 12 insertions, 2 deletions
diff --git a/chapter07/content_ch07.tex b/chapter07/content_ch07.tex
index 56871e7..82a4b01 100644
--- a/chapter07/content_ch07.tex
+++ b/chapter07/content_ch07.tex
@@ -1899,8 +1899,18 @@ The rules for creating the \acs{OVSF} code tree are (derived from the constructi
The different code lengths have benefits and drawbacks.
\begin{itemize}
- \item Longer codes have lower data rates. But they have a higher processing gain and better noise immunity. Data decoding works in noisy environments with low \ac{SNR}.
- \item Short codes give a higher data rate. However, the processing gain is less as well as the noise immunity. Data decoding may not work in noisy environments. A proper \ac{SNR} is required.
+ \item Long codes
+ \begin{itemize}
+ \item Long codes have lower data rates.
+ \item But they have a higher processing gain and better noise immunity. Data decoding works in noisy environments with low \ac{SNR}.
+ \item Furthermore, more users can use the transmission channel, because more orthogonal codes are available (see Figure \ref{fig:ch07:ovsf_code_tree}).
+ \end{itemize}
+ \item Short codes
+ \begin{itemize}
+ \item Short codes give a higher data rate.
+ \item However, the processing gain is less as well as the noise immunity. Data decoding may not work in noisy environments. A proper \ac{SNR} is required.
+ \item Less users can use the transmission channel, because less orthogonal codes are available (see Figure \ref{fig:ch07:ovsf_code_tree}).
+ \end{itemize}
\end{itemize}
\subsection{Asynchronous \acs{DS-CDMA}}