The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
A method to enhance the performance of IDMA system by means of irregular LDPC codes was studied. Interleavers were used as signature character for user identification and iterative turbo detection and decoding approach was employed with reduced complexity. Gaussian approximation was applied to approximate the message probability density function on factor graph with multiple users. Iterative message...
A scheme of applying unequal spreading to LDPC-Coded IDMA system was proposed. The issue of LDPC-Coded IDMA system with equal spreading and unequal spreading was studied. Gaussian approximation was applied to the messages probability density distribution function between nodes on factor graph of LDPC-Coded spreading system. We compare two cases, the first is optimization of LDPC with fixed spreading...
Based on factor graph representation of IDMA (interleave division multiple-access) systems, an interleaver design criterion is proposed. The progressive edge growth (PEG) algorithm proposed for LDPC codes is adapted to multi-user interleavers pattern design. Simulation results show that the designed interleavers perform over random interleavers especially when the number of users is relative large.
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.