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Stefan Parkvall

Bio: Stefan Parkvall is an academic researcher from Ericsson. The author has contributed to research in topics: Telecommunications link & Node (networking). The author has an hindex of 58, co-authored 502 publications receiving 19083 citations. Previous affiliations of Stefan Parkvall include Royal Institute of Technology & University of California, San Diego.


Papers
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Patent
28 Sep 2018
TL;DR: In this article, a wireless transmitter simultaneously transmits (1130) first and second signals in the frequency band in such a manner that the first and the second signals are multiplexed in the spectrum domain in frequency band, and the start time of the symbol interval in the first signal is aligned with the corresponding start time in the second signal at least once per time slot.
Abstract: FIELD: wireless communication equipment.SUBSTANCE: invention generally relates to wireless communication networks and, in particular, multi-mode multi-carrier configurations. In one aspect, the wireless transmitter generates (1110) first signal having a first integer number of symbol intervals in each of one or more time slots of a predetermined length, and generates (1120) second signal having a second integer number of symbol intervals in each of one or more time slots of a predetermined length, the second integer being different from the first integer.EFFECT: wireless transmitter simultaneously transmits (1130) first and second signals in the frequency band in such a manner that the first and second signals are multiplexed in the frequency domain in the frequency band, and in such a manner that the start time of the symbol interval in the first signal is aligned with the corresponding start time of the symbol interval in the second signal at least once per time slot.39 cl, 15 dwg, 2 tbl
Patent
26 Nov 2020
TL;DR: In this article, a method of operating a transmitting node in a millimeter-wave communication network is described, which includes transmitting communication signaling in a transmission timing structure, communication signaling including control signaling and data signaling, the communication signaling further comprising reference signaling common to the control and data signals.
Abstract: There is disclosed a method of operating a transmitting node in a millimeter-wave communication network. The method includes transmitting communication signaling in a transmission timing structure, the communication signaling including control signaling and data signaling, the communication signaling further comprising reference signaling common to the control signaling and data signaling. The disclosure also pertains to related devices and methods.
Patent
19 May 2020
TL;DR: In this article, the authors present a method and apparatus for configuring or pre-configuring random access procedures when there are a plurality of configurable numeric values for one carrier.
Abstract: FIELD: computer equipment.SUBSTANCE: present disclosure provides methods and apparatus for configuring or pre-configuring random access procedures when there are a plurality of configurable numeric values for one carrier. In some embodiments, a random access numerical value of a wireless device is configured using a system information unit. In other embodiments, the random access numeric value used by the wireless device is implicitly determined based on detection of one or more synchronization signals.EFFECT: technical result of this invention is higher flexibility of random access message for arrangement of 5G-systems using mixed numerology.10 cl, 22 dwg
Patent
22 Jun 2017
TL;DR: In this article, a random access message is transmitted to the base station, which receives from the second base station scrambling sequence uplink differing type and uses it for subsequent communication with the radio base station.
Abstract: FIELD: radio engineering, communication.SUBSTANCE: user terminal determines one of uplink scrambling sequences, the first communication type, and generates a random access message using the determined one of uplink scrambling sequences, the first type of communication. The random access message is transmitted to the base station. The user terminal receives from the second base station scrambling sequence uplink differing type and uses it for subsequent communication with the radio base station.EFFECT: provision of opportunities scrambling posts random access uplink.20 cl, 10 dwg

Cited by
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Book
01 Jan 2005

9,038 citations

Journal ArticleDOI
Thomas L. Marzetta1
TL;DR: A cellular base station serves a multiplicity of single-antenna terminals over the same time-frequency interval and a complete multi-cellular analysis yields a number of mathematically exact conclusions and points to a desirable direction towards which cellular wireless could evolve.
Abstract: A cellular base station serves a multiplicity of single-antenna terminals over the same time-frequency interval. Time-division duplex operation combined with reverse-link pilots enables the base station to estimate the reciprocal forward- and reverse-link channels. The conjugate-transpose of the channel estimates are used as a linear precoder and combiner respectively on the forward and reverse links. Propagation, unknown to both terminals and base station, comprises fast fading, log-normal shadow fading, and geometric attenuation. In the limit of an infinite number of antennas a complete multi-cellular analysis, which accounts for inter-cellular interference and the overhead and errors associated with channel-state information, yields a number of mathematically exact conclusions and points to a desirable direction towards which cellular wireless could evolve. In particular the effects of uncorrelated noise and fast fading vanish, throughput and the number of terminals are independent of the size of the cells, spectral efficiency is independent of bandwidth, and the required transmitted energy per bit vanishes. The only remaining impairment is inter-cellular interference caused by re-use of the pilot sequences in other cells (pilot contamination) which does not vanish with unlimited number of antennas.

6,248 citations

Journal ArticleDOI
TL;DR: The gains in multiuser systems are even more impressive, because such systems offer the possibility to transmit simultaneously to several users and the flexibility to select what users to schedule for reception at any given point in time.
Abstract: Multiple-input multiple-output (MIMO) technology is maturing and is being incorporated into emerging wireless broadband standards like long-term evolution (LTE) [1]. For example, the LTE standard allows for up to eight antenna ports at the base station. Basically, the more antennas the transmitter/receiver is equipped with, and the more degrees of freedom that the propagation channel can provide, the better the performance in terms of data rate or link reliability. More precisely, on a quasi static channel where a code word spans across only one time and frequency coherence interval, the reliability of a point-to-point MIMO link scales according to Prob(link outage) ` SNR-ntnr where nt and nr are the numbers of transmit and receive antennas, respectively, and signal-to-noise ratio is denoted by SNR. On a channel that varies rapidly as a function of time and frequency, and where circumstances permit coding across many channel coherence intervals, the achievable rate scales as min(nt, nr) log(1 + SNR). The gains in multiuser systems are even more impressive, because such systems offer the possibility to transmit simultaneously to several users and the flexibility to select what users to schedule for reception at any given point in time [2].

5,158 citations

Journal ArticleDOI
TL;DR: The article consists of background material and of the basic problem formulation, and introduces spectral-based algorithmic solutions to the signal parameter estimation problem and contrast these suboptimal solutions to parametric methods.
Abstract: The quintessential goal of sensor array signal processing is the estimation of parameters by fusing temporal and spatial information, captured via sampling a wavefield with a set of judiciously placed antenna sensors. The wavefield is assumed to be generated by a finite number of emitters, and contains information about signal parameters characterizing the emitters. A review of the area of array processing is given. The focus is on parameter estimation methods, and many relevant problems are only briefly mentioned. We emphasize the relatively more recent subspace-based methods in relation to beamforming. The article consists of background material and of the basic problem formulation. Then we introduce spectral-based algorithmic solutions to the signal parameter estimation problem. We contrast these suboptimal solutions to parametric methods. Techniques derived from maximum likelihood principles as well as geometric arguments are covered. Later, a number of more specialized research topics are briefly reviewed. Then, we look at a number of real-world problems for which sensor array processing methods have been applied. We also include an example with real experimental data involving closely spaced emitters and highly correlated signals, as well as a manufacturing application example.

4,410 citations

Proceedings Article
01 Jan 1991
TL;DR: It is concluded that properly augmented and power-controlled multiple-cell CDMA (code division multiple access) promises a quantum increase in current cellular capacity.
Abstract: It is shown that, particularly for terrestrial cellular telephony, the interference-suppression feature of CDMA (code division multiple access) can result in a many-fold increase in capacity over analog and even over competing digital techniques. A single-cell system, such as a hubbed satellite network, is addressed, and the basic expression for capacity is developed. The corresponding expressions for a multiple-cell system are derived. and the distribution on the number of users supportable per cell is determined. It is concluded that properly augmented and power-controlled multiple-cell CDMA promises a quantum increase in current cellular capacity. >

2,951 citations