André Noll Barreto

Learn More
In this paper we propose two precoding schemes for the downlink of CDMA systems which help reduce the multiuser interference by jointly precoding the transmitted signal based on knowledge of the downlink channel. These methods provide a substantial capacity increase without requiring complex multiuser detectors at the mobile terminals and can be applied for(More)
—The downlink capacity tends to be the limiting factor in future communications systems. In this paper, we propose two schemes for the downlink of code-division multiple-access systems that help reduce the multiuser interference by jointly precoding the transmitted signal based on knowledge of the downlink channel. Methods that operate on blocks of bits(More)
Spread-spectrum systems are used to transmit over frequency selective fading channels. The RAKE receiver is a well-established technique to exploit the multipath diversity. However, if the channel impulse response (CIR) is known a priori in the transmitter, the signal can be precoded to increase the SNR at the receiver while the transmit power remains(More)
In this paper we present an interference analysis which reveals capacity reserves for a hierarchical GSM radio network. In the investigated concept a low-power Cordless Telephony System reuses the frequencies of a cellular GSM system based on Total Frequency Hopping (T-FH) multiple access. Based on a novel simulation method, which considers the dynamics of(More)
'Mobile communications is characterized by a fast growing number of users and an increasingly heterogeneous data traffic due to emerging multimedia packet services. Likewise, users desire more mobility support, thus demanding permanent availability at any place and any speed. The conventional answer to this problem is building new wireless standards. But(More)
In this paper, the capacity in the Integrated Broad-band Mobile System (IBMS) is studied. This new mobile system approach utilizes smart antennas. Capacity increase due to smart antennas has already been investigated, but typically only concerning the number of users per cell. But IBMS follows the approach to support higher data rates with the use of smart(More)