IDMA – the future of wireless technology
                     IDMA – THE FUTURE OF 
WIRELESS 
TECHNOLOGY
INTRODUCTION
As wireless broadband 
communication has been 
experiencing a tremendous growth 
in past few year, the demands for 
various new & advanced multiple 
access techniques is increasing 
consistently. We can experience 
many new multiple access 
techniques in 3G & 4G.
Source: edelweisspublications.com
TURBO-CODE
The most important in IDMA is 
turbo-code which has increased the 
efficiency of 4G to a larger extent. 
By using these turbo codes with 
interleave division multiple excess 
the data rates 4G technology has 
been increased significantly. 
Source: edelweisspublications.com
SWITCH TO IDMA 
FROM OFDM
The main reason to switch to IDMA 
from OFDM is the complexities that 
were observed in OFDM. 
In OFDM, for all the signals to 
maintain orthogonality amongst 
themselves was the major 
challenge and many times it can be 
observed that even if a single signal 
on the entire bandwidth losses 
orthogonality then all the signals on 
that bandwidth are affected.
Source: edelweisspublications.com
HOW IT WORKS?
Whenever a signal is transmitted 
from mobile to base station or vice 
versa, the signal uses a dedicated 
bandwidth, this bandwidth is been 
allocated to multiple users from its 
respective service providers; the 
multiple access techniques allows 
all the users to communicate with 
the base station of its respective 
service providers or with any other 
users of any particular service 
providers efficiently. 
Source: edelweisspublications.com
MAIN CHALLENGE
In IDMA system, the main challenge 
is to avoid ISI in the non-orthogonal 
signals, since here signal are not 
orthogonal as in OFDM.
Source: edelweisspublications.com
IDMA PRINCIPLE
Interleaver is the heart of IDMA 
system. IDMA is often called as the 
next generation multiple access 
techniques for CDMA and also for 
OFDM. 
In IDMA different users can use 
different types of Interleavers and 
also Interleavers are used to 
differentiate the signals on entire 
bandwidth spectrum.
Source: edelweisspublications.com
TYPES OF 
INTERLEAVERS
• Random Interleavers: This form 
the easiest way for the symbols 
to spread across the spectrum 
using Interleavers.
• Master Random Interleavers: 
Master Random Interleavers is 
similar to random Interleavers in 
its functioning but it overcomes 
the drawbacks encountered in 
random Interleavers.  
Source: edelweisspublications.com
TYPES OF 
INTERLEAVERS 
CONT.
• Tree Based Interleaver: Main 
objective here in tree-based 
Interleaver is to overcome the 
issue of memory consumption in 
random and power Interleaver 
and also to overcome the 
computational complexities 
encountered in each of them 
respectively.
Source: edelweisspublications.com
PERFORMANCE 
PARAMETER
• BER (Bit Error Rate) parameter is 
used to compare the 
performance of digital system .
Source: edelweisspublications.com
FUTURE SCOPE
• In regards with all the 
advantages IDMA have got, it 
will be very interesting to see 
the role of IDMA in 5G (where 
the proposed multiple access 
technique is BDMA an advanced 
version of IDMA) as it has 
already left an outstanding 
impact in 4G. 
Source: edelweisspublications.com