Showing papers by "Stefan Parkvall published in 2000"
TL;DR: The uplink performance in a cellular direct-sequence code-division multiple-access system using long and short spreading sequences is compared in terms of the distribution of the bit-error probability.
Abstract: The uplink performance in a cellular direct-sequence code-division multiple-access system using long and short spreading sequences is compared in terms of the distribution of the bit-error probability. Three different receiver types are considered: conventional; MMSE; and interference cancellation, both with and without forward-error correction. The short code system has a slightly higher performance variability among the user population than the corresponding long code system, which requires attention when designing a short code system. Code hopping as a technique to mitigate this is investigated.
52 citations
15 May 2000
TL;DR: It is found that transmit diversity can greatly improve the system capacity, both at the link and system levels.
Abstract: In the current WCDMA standard, support for transmit diversity is provided in the down-link to combat fading and changing interference situations. The base station (node B) is equipped with two transmit antennas, while the terminal (user equipment, UE) uses only a single antenna. This arrangement is advantageous compared to receive diversity as it removes the need for two antennas in the terminal. This paper describes the various transmit diversity schemes in WCDMA and gives simulation results, both at the link and system levels. It is found that transmit diversity can greatly improve the system capacity.
36 citations
25 Jun 2000
TL;DR: An approach to code design for joint channel estimation, equalization and error correction is proposed where the code is designed based on knowledge of the receiver structure and the statistical properties of the channel.
Abstract: The problem of data transmission over an unknown channel is considered and an approach to code design for joint channel estimation, equalization and error correction is proposed. In contrast to most traditional approaches, where the receiver is designed given knowledge of the code used at the transmitter, this paper proposes an approach where the code is designed based on knowledge of the receiver structure and the statistical properties of the channel.
3 citations