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.

Radio node, wireless device and methods for carrier aggregation control information

Abstract: The present invention relates to a radio node ( 212 ), a wireless device ( 220 ) and methods performed by the radio node ( 212 ) and the wireless device ( 220 ) for communicating in a wireless communication system ( 200 ). The wireless device ( 220 ) is configured with cells on at least two component carriers, CCs, available to the wireless communication system ( 200 ) for communication with the wireless device ( 220 ). Each one of the at least two CCs is associated with at least one CC group out of a set of CC groups. The radio node ( 212 ) transmits control information to the wireless device ( 220 )indicating a CC group. The transmitted control information applies to at least one CC, which at least one CC is at least one of those CCs, out of the at least two CCs, that are associated with the indicated CC group. The wireless device ( 220 ) receives the control information from the radio node ( 212 ) and applies the received control information to at least one CC, which at least one CC is at least one of those CCs, out of the at least two CCs, that are associated with the indicated CC group.

Node B-Control-Proxy

Abstract: The present invention relates to a first node and a second node in a mobile telecommunication network. The network comprises a first node, a second node and a third node, wherein the first node is connectable to the second node and the second node is connectable to the first node and to the third node and the third node is connectable to the second node. A system function is realized by the execution of a master-process implemented in the first node and a slave-process implemented in the third node, wherein the execution of the master-process realizes a control function associated with the system function. The master-process of the first node is adapted to temporarily delegate the responsibility to realize the control function to a master-proxy-process implemented in the second node and the master-proxy-process implemented in the second node is adapted to take over the responsibility to realize the control function from the master-process of the first node.

Harq handling for nodes with variable processing times

Abstract: A method for use in a transmitter includes sending a transmission comprising a transport block (TB) comprising a plurality of code blocks (CBs) arranged in one or more code block groups (CBGs). Each code block group includes one or more code blocks and each code block includes a plurality of coded bits. The transmission is sent to a receiver configured to use multi-bit hybrid automatic repeat request (HARQ) feedback per transport block. The method further includes receiving HARQ ACK or NACK feedback from the receiver one or more of the one or more code block groups of the transport block. The method further includes determining a number of code blocks or code block groups to send to the receiver in a retransmission based on at least the received HARQ ACK or NACK feedback.

Method of reducing feedback signalling using sic

Abstract: The present invention relates to a method and arrangements for reducing signalling in a communications system by reducing feedback and/or forward transmission signalling. The system comprises receivers and transmitters for transmission of signal streams. Each stream is encoded. The receiver indicates an identity of the latest correctly decoded uniquely encoded stream.

Near-far resistant receivers without a priori synchronization for asynchronous DS-CDMA systems

Abstract: A receiver for data demodulation in an asynchronous direct-sequence code-division multiple access (DS-CDMA) system without prior knowledge of the propagation delays is proposed. Special attention is paid to the near-far problem and the proposed schemes are experimentally shown to be near-far robust. The near-far robustness is obtained by estimating the a priori unknown propagation delay using a subspace based technique. Quantities obtained in the estimation procedure are subsequently used to design a filter, used for suppression of interference, according to the minimum mean-squared error criterion. A simple two-state Viterbi algorithm is used for the data demodulation.

Noncooperative Cellular Wireless with Unlimited Numbers of Base Station Antennas

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.

Scaling Up MIMO: Opportunities and Challenges with Very Large Arrays

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].

Two decades of array signal processing research: the parametric approach

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.

On the capacity of a cellular CDMA system

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. >