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.
In the polarization-division multiplexed coherent optical fiber communication, conventional orthogonal frequency-division multiplexing (OFDM) and discrete Fourier transform spread OFDM (DFT-S-OFDM) sacrifice the baud rate with either zero-padded subcarriers in the high-frequency region to mitigate the frequency fading, or with a large cyclic prefix (CP) to eliminate the residual inter-symbol interference...
This paper focuses on the feedback scheme for downlink Multi-User Multiple-Input Multiple-Output (MU-MIMO) transmission with linear precoding. When the maximum transmission rank per user is limited to one, the multiple-antenna receiver uses a weight vector to transform MIMO channel matrix into an equivalent Multiple-Input Single-Output (MISO) channel vector. Then a Channel Directional Index (CDI)...
This paper proposes a differential codebook-based method to reduce the feedback overhead for closed-loop MIMO-OFDM systems. With the assumed multimode transmit precoding, both the number of data streams (rank) and the index of precoding matrix are fed back to the transmitter at each sub-band. By exploiting the channel correlation in frequency domain, an enhanced differential codebook (a subset of...
The approximate minimum average symbol error rate (SER) precoder is designed for spatial multiplexing (SM) system in Ricean channels. Based on long-term channel state information (CSI), a closed-form solution that combines eigen-beamforming (E-BF) and power allocation is presented for correlated Ricean channel. Moreover, a simple precoder only based on K-factor and line-of-sight (LOS) departure angle...
The transmitter side precoding shows excellent performance for multiuser multiple input multiple output (MIMO) wireless systems. However, joint transmitter and receiver design might achieve further improvement. The optimum precoding and decoding matrices can be solved iteratively. In this paper, we propose a modified joint iterative algorithm, based on minimum mean square error (MMSE) criterion in...
This paper proposes a codebook based limited feedback zero-forcing(ZF) precoding scheme for multi-user multiple-input multiple-output (MIMO) downlink channels. In such system, each user needs to calculate a channel directional index (CDI) and a channel quality indicator (CQI), feedback them to the base station (BS). BS selects the set of active users, and calculates transmit beams through zero forcing...
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.