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.
As a special class of space-time code, space-time trellis coding (STTC) can achieve the best compromise of coding complexity, performance and bandwidth efficiency. In the paper, we present a MIMO-OFDM system model basing on the STTC. Firstly, we generally describe the framework and the basic principles of the STTC-MIMO-OFDM system. Then simulation is performed under the case of different time delay,...
In multiple-relay cooperative wireless networks, opportunistic relaying is a promising scheme, where the most challenging problem is to choose the best relay efficiently. The traditional opportunistic relay selection scheme is based on the channel conditions of source-relay (S-R) and relay-destination (R-D) links. In comparison with conventional narrowband networks, an appealing merit of impulse radio...
A bit loading algorithm is presented for orthogonal frequency division multiplexing (OFDM) systems to minimize bit error rate (BER), where quadrature amplitude modulation (QAM) is employed. The target data bits are loaded onto selected subcarriers that have largest remaining signal-to-noise ratio (SNRrem) values on a group-by-group basis. The number of iterations is determined by the maximum size...
This paper focuses on the coexistence problem of multi-band orthogonal frequency division multiplexing (MB-OFDM) ultra-wideband (UWB) systems and current radio systems such as IEEE802.11a. Aiming at improving the performance of MB-OFDM UWB, we attempt to avoid interferences from IEEE802.11a systems. The cognitive radio (CR) technology is introduced to detect the distribution of co-channel interferences...
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.