Showing papers by "Stefan Parkvall published in 2015"

Ultra-dense networks in millimeter-wave frequencies

Abstract: Demands for very high system capacity and end-user data rates of the order of 10 Gb/s can be met in localized environments by Ultra-Dense Networks (UDN), characterized as networks with very short inter-site distances capable of ensuring low interference levels during communications. UDNs are expected to operate in the millimeter-wave band, where wide bandwidth signals needed for such high data rates can be designed, and will rely on high-gain beamforming to mitigate path loss and ensure low interference. The dense deployment of infrastructure nodes will make traditional wire-based backhaul provisioning challenging. Wireless self-backhauling over multiple hops is proposed to enhance flexibility in deployment. A description of the architecture and a concept based on separation of mobility, radio resource coordination among multiple nodes, and data plane handling, as well as on integration with wide-area networks, is introduced. A simulation of a multi-node office environment is used to demonstrate the performance of wireless self-backhauling at various loads.

Why to Decouple the Uplink and Downlink in Cellular Networks and How To Do It

Abstract: Ever since the inception of mobile telephony, the downlink and uplink of cellular networks have been coupled, i.e. mobile terminals have been constrained to associate with the same base station (BS) in both the downlink and uplink directions. New trends in network densification and mobile data usage increase the drawbacks of this constraint, and suggest that it should be revisited. In this paper we identify and explain five key arguments in favor of Downlink/Uplink Decoupling (DUDe) based on a blend of theoretical, experimental, and logical arguments. We then overview the changes needed in current (LTE-A) mobile systems to enable this decoupling, and then look ahead to fifth generation (5G) cellular standards. We believe the introduced paradigm will lead to significant gains in network throughput, outage and power consumption at a much lower cost compared to other solutions providing comparable or lower gains.

Field experiments on 5G radio access using 15-GHz band in outdoor small cell environment

Abstract: This paper presents outdoor field experimental results showing the achievement of 3-Gbps throughput performance based on 400-MHz bandwidth transmission when applying carrier aggregation with 4 component carriers and 4-by-4 single-user multiple-in multiple-out multiplexing in the 15-GHz frequency band in the downlink of 5G cellular radio access. A new radio interface with time division duplexing and radio access based on orthogonal frequency-division multiplexing is implemented in a 5G testbed to support ultra-high speed transmission with low latency. Experimental results in an outdoor open-space parking area show that the peak throughput is 2.8 Gbps in front of a base station (BS) antenna with a high reference signal received power (RSRP) although rank 2 is selected due to the high antenna correlation. The results also show that the average throughput of 2 Gbps is achieved 120 m from the BS antenna. In a courtyard enclosed by building walls, 3.6 Gbps is achieved in an outdoor-to-outdoor environment with a high RSRP and in an outdoor-to-indoor environment where the RSRP is lower due to the penetration loss of glass windows, but a multipath rich environment contributes to actualizing a low antenna correlation.

Resource allocation for data transmission in wireless systems

Abstract: Techniques are disclosed for allocating time-frequency resources in a system that uses multiple multicarrier modulation numerologies. According to one aspect, a method in a first wireless node comprises allocating (1310) time-frequency resources for use by a second wireless node, where said allocating comprises selecting, for use in multicarrier modulation in the allocated time-frequency resources, one of two or more subcarrier bandwidths that the second wireless node is adapted to use for modulating or demodulating of data. In some embodiments, the method further comprises sending (1320) resource allocation information to the second wireless node, the resource allocation information identifying the allocated time-frequency resources.

A Wireless Device, a Radio Node, and Methods Therein

Abstract: A wireless device 108 and a method therein for assisting in precoder selection for wireless communication with a Radio Node (RN) 106 , and a RN 106 for performing precoder selection for wireless communication with a wireless device 108 . The wireless device is configured with a set of precoders. The wireless device determines a subset of precoders out of the set of precoders; and transmits, to the RN, at least one Sounding Reference Signal (SRS) precoded with a respective at least one precoder comprised in the subset. The RN receives, from the wireless device, at least one SRS precoded with a respective at least one precoder comprised in a subset of precoders; and transmits, to the wireless device, a signal indicative of a selected precoder to be used for a transmission to the RN, wherein the selected precoder is indirectly selected based on the received at least one SRS.

Field Experiments on 5G Radio Access Using Multi-Point Transmission

Abstract: This paper presents outdoor field experimental results to clarify the 4x4 MIMO throughput performance from applying multi-point transmission in the 15 GHz frequency band in the downlink of 5G cellular radio access system. The experimental results in large-cell scenario shows that up to 30 % throughput gain compared to non-multi-point transmission is achieved although the difference for the RSRP of two TPs is over 10 dB, so that the improvement for the antenna correlation is achievable and important aspect for the multi-point transmission in the 15 GHz frequency band as well as the improvement of the RSRP. Furthermore in small-cell scenario, the throughput gain of 70% and over 5 Gbps are achieved applying multi-point transmission in the condition of two different MIMO streams transmission from a single TP as distributed MIMO instead of four MIMO streams transmission from a single TP.

A Trial System for 5G Wireless Access

Abstract: 5G is the next step in the evolution of mobile communication and a key component of the future networked society. With capabilities such as massive system capacity, higher data rates, very low latency and ultra-high reliability, 5G will provide significantly enhanced mobile-broadband experience but also support a wide range of new wireless applications and use cases. In this paper, a trial system for 5G mobile broadband operating at 15 GHz is outlined, together with initial experimental results showing that multi-Gbps data rates are possible.

Methods, Base Station and Wireless Device for Supporting Radio Communication

Abstract: A base station(300), a wireless device (302)and methods thereinfor supporting radio communication, wherein the base station(300) employs carrieraggregation with multiple carriers serving a primary cell, PCell, and at least one secondary cell, SCell.Thebase station(300)signals (3:3) an SCell status to the wireless device (302), the SCell status indicating whether the at least one SCell will bein active state where thebase station(300) transmits downlink signals on a carrier serving the at least one SCell, or in inactive statewhere thebase station(300) does not transmit downlink signals on the carrier serving the at least one SCell. Thereby, thewireless device (302) canadapt its behaviour depending on the signalled SCell status, e.g. by turning off its receiver and not perform any signal measurements when the SCell is in inactive state.

Control of timing for mixed-mode multicarrier modulation

Abstract: In one aspect, a wireless transmitter forms (1110) a first signal having a first integer number of symbol intervals in each of one or more time intervals of a predetermined length and forms (1120) a second signal having a second integer number of symbol intervals in each of the one or more time intervals of the predetermined length, the second integer number differing from the first integer number. The wireless transmitter simultaneously transmits(1130) the first and second signals in a frequency band, such that the first and second signals are frequency- domain multiplexed in the frequency band and such that a symbol interval starting time in the first signal is aligned with a corresponding symbol interval starting time in the second signal at least once per time interval.

5G Wireless Access

Abstract: This chapter covers the background to, and basic principles for 5G wireless access. It describes the key requirements for 5G wireless access, including the requirements of IMT-2020 as defined by ITU. It goes on to discuss the 5G spectrum situation and the overall structure of 5G wireless access consisting of the evolution of LTE in combination with a new radio-access technology. Finally, it gives an overview of the 3GPP process with regard to 5G, including the time schedule developed to ensure timely 5G commercial introduction in 2020.

Interference Randomization of Control Channel Elements

Abstract: A method and a radio base station for interleaving control channel data to be transmitted in a telecommunications system are described. The method comprises grouping the control channel elements CCE1-CCEn into a first order of control channel symbol groups, adding symbol groups comprising dummy values or zeros to the first order of control channel symbol groups based on a number of available symbol group positions for the shared control channel, interleaving the first order of the control channel symbol groups resulting in an a second order, and mapping the second order of control channel symbol groups to the available control channel transmission resources.

The Fundamentals for Mobile Broadband, HSPA Evolution

Abstract: This book is essential reading for those wishing to obtain a systems perspective and a broad view on the background, performance and application of the latest developments in HSPA in the context of the demands on todays mobile broadband devices and networks. It takes the reader behind the scenes of 3GPP and provides an easily accessible understanding of the basic principles, the latest steps in the standards evolution, and the motivations behind the development of standardized features. It covers important topics such as smartphone related features, multi-carrier and multi-antenna operation, interface architecture, heterogeneous networks and HSPA system performance. Offering full coverage of recent developments in HSPA up to Release 13, this book will provide a comprehensive description of one of the dominating standards for mobile broadband.

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.

Method and apparatuses for operating a wireless communication network

Abstract: The present disclosure pertains to a method for operating a wireless communication network, wherein a first member of the network transmits a scheduling message to a secondary member of the network and the secondary member receives the scheduling message. The secondary member schedules sounding signal transmissions and/or a corresponding schedule based on the scheduling message, wherein the scheduling message and/or the sounding signal schedule refers to a schedule for sounding signals based on a status of beam forming performed in the network and/or wherein the sounding signal schedule and/or the schedule message refers to a compact schedule of sounding signals. There are also disclosed associated devices and methods.

Multimedia broadcast multicast services

Abstract: In the past, cellular systems have mostly focused on transmission of data intended for a single user and not on broadcast services. Traditional broadcast networks, exemplified by the radio and TV broadcasting networks, have on the other hand focused on covering very large areas and have offered no or limited possibilities for transmission of data intended for a single user. Multimedia Broadcast and Multicast Services (MBMS), introduced for WCDMA in release 6, supports multicast/broadcast services in a cellular system, thereby combining multicast and unicast transmissions within a single network. With MBMS, the same content is transmitted to multiple users located in a specific area, the MBMS service area , in a unidirectional fashion. The MBMS service area typically covers multiple cells, although it can be made as small as a single cell. In this chapter, the principles behind MBMS in the radio access network and their introduction into WCDMA are discussed.

Radio resource allocation of unlicensed frequency bands based on utilization rate of primary and secondary channels on one of the sharing technologies

Abstract: A method of a network node is disclosed. The network node is adapted to operate in accordance with a first radio access technology for allocation of radio resources of a frequency band (e.g. an unlicensed frequency band) to communication in accordance with the first radio access technology, wherein communication according to a second radio access technology may occupy one or more of the radio resources of the frequency band. The method comprises receiving a beacon signal associated with the second radio access technology and determining whether or not the beacon signal comprises information indicative of which of the radio resources of the frequency band are used as primary and secondary channels, respectively, in accordance with the second radio access technology. The method also comprises determining a communication activity rate of at least one of the radio resources of the frequency band. The method also comprises selecting one or more of the radio resources of the frequency band based on the determined communication activity rate (wherein, if the beacon signal comprises information indicative of which of the radio resources of the frequency band are used as primary and secondary channels, the selection is further based on the information), and allocating one or more of the selected radio resources to communication in accordance with the first radio access technology. Corresponding scheduler, network node and computer program product are also disclosed.

Signaling of antenna associations

Abstract: For future wireless systems, it is desired to keep network implementation aspects, such as transmission point selection, precoder selection, etc, transparent to the terminal. This means that terminals are envisaged to be unaware of e.g. from which specific network node a transmission is made. This may be referred to as the transparency principle. The proposed solution comprises enabling a receiver to determine a type of antenna association that may be assumed in regard of two blocks of information, based on the result of the decoding of e.g. the first data block. The determination is done in a way such that the principle of transparency is not broken.

High-speed uplink packet access

Abstract: High-Speed Uplink Packet Access (HSUPA), also known as Enhanced Uplink , was introduced in WCDMA release 6. It provides improvements in WCDMA uplink capabilities and performance in terms of higher data rates, reduced latency, and improved system capacity and is therefore a natural complement to HSDPA. Together, the two are commonly referred to as High-Speed Packet Access (HSPA). This chapter describes in detail release 6 HSUPA since HSUPA is the fundamental uplink building block of the subsequent HSPA evolution. Subsequent chapters then elaborate on the enhancements to the release 6 HSUPA framework that were introduced in later releases.

Using a precoded multi-carrier modulation scheme in a wireless communication network

Abstract: A method performed by a communication node (110, 121) for transmission using a precoded multi-carrier modulation scheme in a wireless communications network (100) is provided The communication node splits a precoded multi-carrier symbol into at least a first symbol part and at least a second symbol part Also, the communication node modulates the at least first and second symbol parts such that the first symbol part of the precoded multi-carrier symbol is used for transmission of a reference signal and the second symbol part of the precoded multi-carrier symbol is used for transmission of data and/or control information Then, the communication node transmits the reference signal and the data and/or control information in the modulated precoded multi-carrier symbol

Multi-antenna transmission

Abstract: Support for efficient multi-antenna transmission techniques is fundamental for any modern communication system to meet the demand of increased data rates from today’s mobile broadband users. Tools for enabling improved and more efficient use of multiple transmit and receive antennas for WCDMA/HSPA have been a key area of research and standardization in 3GPP for many years, and the current standard supports a flexible toolbox to facilitate multi-antenna transmission techniques. This chapter examines in detail the signaling and procedures associated with HSPA multi-antenna features, including downlink Tx diversity, two-branch MIMO, and four-branch MIMO, as well as uplink closed- and open-loop Tx diversity and UL MIMO, within the context of the history of the development of multi-antenna features from release 5 to release 11.

Methods and apparatuses for controlling timing of feedback transmissions

Abstract: There is disclosed a method for controlling the timing of feedback transmissions by a communication device (80) communicating over a communication link (70), wherein the communication link supports a retransmission scheme. The method comprises transmitting (42) a feedback timing indicator, FTI, wherein the indicator is selected from a set of indicators.

Resource scheduling of uplink resources

Abstract: The present embodiments herein provide methods, apparatuses and a system for the purpose of scheduling resources to a UE (11) by a network node (12). The UE or CE (11) is configured to receive (210), from the network node (12), a control message, comprising information about a resource allocation as well as an indicator indicating whether a single-subframe scheduling scheme or a multi-subframe scheduling scheme. The CE (11) then retrieves the indicator and act according the information associated with the indicator.

Overview of release 99 WCDMA

Abstract: This chapter provides a brief overview of WCDMA release 99 to serve as a background to subsequent chapters. WCDMA is a versatile and highly flexible radio interface that can be configured to meet the requirements from a large number of services, but the focus for the description is the functionality commonly used to support packet-data transmissions. The goal of this description is to provide sufficient background to the underlying release 99 WCDMA specifications such that HSPA and the HSPA enhancements that are described in subsequent chapters can be seen in context.

CDMA transmission principles

Abstract: HSPA is built upon release 99 Wideband CDMA, which is a technology based on the concept of spread spectrum transmission. The spread spectrum technique emerged out of military research as a basis for communications that aim to flexibly multiplex multiple users and services and to provide robustness against external interference. This chapter reviews some of the basics of spread spectrum techniques and building blocks that are required for a successful communications link and develops a baseband transmitter model. Impacts of multipath radio propagation effects on spread spectrum signals are examined, together with a short overview of receiver equalization strategies.

Method and apparatus for reporting channel state information in a telecommunication system

Abstract: A method and an arrangement (800) in a user equipment (420) for reporting Channel State Information, CSI, and a method and an arrangement (1000) in a base station (410) for obtaining CSI are provided. The user equipment (420) is in connection with the base station (410) in a cellular communication network (400). After receiving a receiving (702) a grant in a subframe n to be used for CSI reporting, from the base station, the user equipment determines (703) subframe type of a subframe n+p. The user equipment then reports (704) to the base station, CSI reflecting channel conditions in the subframe type of subframe n+p. p is a variable value.

Efficient multi-tti scheduling for uplink tdd

Abstract: Systems and methods are disclosed for transmission and reception of an uplink grant during a gap created in radio resources assigned by a previous multiple Transmit Time Interval (multi-TTI) uplink grant in a system operating according to a Time Division Duplexing (TDD) scheme. In one embodiment, a 5 method of operation of a radio network node (12) in a cellular communications network (10) is provided. The method includes transmitting a first uplink grant that assigns radio resources for a multi-TTI uplink transmission, and transmitting a second uplink grant during a gap in the radio resources assigned by the first uplink grant. In one embodiment, by utilizing the gap to transmit the second 10 uplink grant, uplink radio resources assigned for uplink transmission can be maximized, which is particularly beneficial in high uplink traffic conditions.

Introduction to HSPA

Abstract: Following the standardization of WCDMA in early 2000, it was soon recognized that the existing 3G technology would need to evolve to meet the challenges of the era of mobile broadband. Shifts in technology, user behavior, traffic models, business models, and the learning curve of the early phases of 3G deployment drove a research effort that lead to the evolution from the release 99 specifications to modern HSPA. Today, HSPA stands alongside LTE as one of 3GPP’s market-leading air interfaces, capable of around 346 Mbps in downlink and 34 Mbps in uplink. With around two billion subscribers worldwide in 2014, demand for traffic and technology evolution in HSPA continues to grow. This chapter provides an overview of the HSPA evolution path over 3GPP releases 5 to 11 by describing each of the main building blocks.

Multi-flow transmission

Abstract: Multi-flow transmission , also referred to as HSDPA multi-flow data transmission , was introduced in WCDMA release 11. It enables improved user experience for cell-edge UEs located in the soft or softer handover coverage region of two cells on the same carrier frequency by allowing HS-PDSCH to be scheduled from both cells. Such operation allows more scheduling opportunities for the network, aids system load balancing, and improves cell-edge throughputs. Multi-flow operation relies on simultaneous reception of up to four HS-DSCH transport channels in the CELL_DCH state on up to two frequencies, of which a maximum of two HS-DSCH transport channels may reside at the same frequency and belong either to same or different Node Bs. This chapter describes in detail the release 11 Multi-flow feature.