Antti Sorri

Bio: Antti Sorri is an academic researcher from Nokia. The author has contributed to research in topics: User equipment & Wireless network. The author has an hindex of 18, co-authored 54 publications receiving 1443 citations. Previous affiliations of Antti Sorri include Nokia Networks.

License-exempt LTE deployment in heterogeneous network

Abstract: Mobile broadband data usage in Long Term Evolution (LTE) networks is growing exponentially and capacity constraint is becoming an issue. Heterogeneous network, WiFi offload, and acquisition of additional radio spectrum can be used to address this capacity constraint. Licensed spectrum, however, is limited and can be costly to obtain. This paper investigates deploying LTE on a license-exempt band as part of the pico-cell underlay. Coexistence mechanism and other modifications to LTE are discussed. Performance analysis shows that LTE can deliver significant capacity even while sharing the spectrum with WiFi systems.

System performance of LTE and IEEE 802.11 coexisting on a shared frequency band

Abstract: This paper presents the system performance analysis of 3GPP Long-Term Evolution (LTE) and IEEE 802.11 Wireless Local Area Networks (WLAN) in a situation where LTE downlink (DL) has been expanded over to unlicensed frequency band usually used by WLAN. Simple fractional bandwidth sharing mechanism is used to allow both technologies to transmit. The system performance is evaluated by means of fully dynamic network simulations.

Power Control For LTE Deployment In Unlicensed Band

Abstract: Methods of power control for LTE transmissions in unlicensed bands are described. One method includes determining, at a first device (such as a LTE UE or LTE eNB), a scheduled transmission window for a LTE transmission in an unlicensed band. The transmission window indicates a time for sending the transmission in the unlicensed band. Prior to the scheduled transmission window, the method also includes determining whether a WiFi transmitter is transmitting a signal in the unlicensed band. The method also includes, in response to determining that the transmitter is transmitting in the unlicensed band, determining an adjusted transmission power for the transmission and sending the transmission (such as from an LTE UE to an LTE eNB or from an LTE eNB to an LTE UE) in the transmission window at the adjusted transmission power. Apparatus and computer readable media are also described.

Methods, apparatuses and computer program products for configuring frequency aggregation

Abstract: An apparatus for determining whether to deactivate a secondary cell includes a processor and memory storing executable computer program code that cause the apparatus to at least perform operations including determining that a secondary cell should be deactivated based on a measurement(s) of the secondary cell or received information associated with frequency spectrum of the secondary cell. The computer program code may cause the apparatus to generate a deactivation message responsive to the measurement(s) indicating secondary cell interference or the received information indicating that the apparatus should no longer use the frequency spectrum. The computer program code may cause the apparatus to provide the deactivation message to a network device. Corresponding methods and computer program products are also provided.

Using unique preambles for D2D communications in LTE

Abstract: A method is disclosed that includes determining a preamble, at least a portion of which is unique to one or more user equipment for a device-to-device communication of one or more subframes on a band, and performing the device-to-device communication of the one or more subframes comprising the preamble on the band. The band could be, e.g., a lightly-licensed band, a licensed-exempt or unlicensed band, a secondary usage of a band of the licensed band, a band in TV white space, or a licensed band. Apparatus and computer program products are also disclosed.

User terminal, radio base station and radio communication method

Abstract: The present invention is designed to provide a user terminal, a radio base station and a radio communication method of novel structures that can achieve a good communication environment. A radio base station non-orthogonal-multiplexes downlink signals for a plurality of user terminals over a given radio resource, a user terminal having received the downlink signals for the plurality of user terminals decodes downlink signal for another user terminal, judges whether or not the downlink signal for the other user terminal has been successfully received, based on the decoding result of the downlink signal, reports a judgement result as to whether or not the downlink signal for the other user terminal has been successfully received and a judgement result as to whether or not a downlink signal for the user terminal has been successfully received, to the radio base station, and then the radio base station executes retransmission control of downlink signals based on reports from the user terminal.

Telecommunications apparatus and methods

Abstract: A wireless telecommunication system comprises base stations for communicating with terminal devices. One or more base stations support a power boost operating mode in which a base station's available transmission power is concentrated in a subset of its available transmission resources to provide enhanced transmission powers as compared to transmission powers on these transmission resources when the base station is not operating in the power boost mode. A base station establishes an extent to which one or more base stations in the wireless telecommunications system support the power boost operating mode conveys an indication of this to a terminal device. The terminal device receives the indication and uses the corresponding information to control its acquisition of a base station of the wireless telecommunication system, for example by taking account of which base stations support power boosting and/or when power boosting is supported during a cell attach procedure.

Method and apparatus to facilitate support for multi-radio coexistence

Abstract: A method of wireless communication includes monitoring coexistence issues among supported radios in a User Equipment (UE). The method includes determining a coexistence policy for communication resource operation within a user equipment (UE) and configuring communication resources of the user equipment in accordance with the determined coexistence policy. The policy may give priority to an LTE modem, an ISM modem, or may implement a variable priority scheme. The policy may be communicated to each modem from a host over a software messaging communication line. Modems in the UE may communicate with each other through logical lines providing real time communication. The policy may determine the operation of each modem and the treatment of the logical lines by each modem.

LTE-unlicensed: the future of spectrum aggregation for cellular networks

Abstract: The phenomenal growth of mobile data demand has brought about increasing scarcity in available radio spectrum. Meanwhile, mobile customers pay more attention to their own experience, especially in communication reliability and service continuity on the move. To address these issues, LTE-Unlicensed, or LTEU, is considered one of the latest groundbreaking innovations to provide high performance and seamless user experience under a unified radio technology by extending LTE to the readily available unlicensed spectrum. In this article, we offer a comprehensive overview of the LTEU technology from both operator and user perspectives, and examine its impact on the incumbent unlicensed systems. Specifically, we first introduce the implementation regulations, principles, and typical deployment scenarios of LTE-U. Potential benefits for both operators and users are then discussed. We further identify three key challenges in bringing LTE-U into reality together with related research directions. In particular, the most critical issue of LTE-U is coexistence with other unlicensed systems, such as widely deployed WiFi. The LTE/WiFi coexistence mechanisms are elaborated in time, frequency, and power aspects, respectively. Simulation results demonstrate that LTE-U can provide better user experience to LTE users while well protecting the incumbent WiFi users’ performance compared to two existing advanced technologies: cellular/WiFi interworking and licensed-only heterogeneous networks (Het-Nets).

Radio base station, user terminal, and radio communication method

Abstract: The present invention is designed to improve spectral efficiency in a radio communication system which can use non-orthogonal multiple access (NOMA). Steps are provided in which a radio base station configures one of a plurality of transmission mode including a first transmission mode, which groups a plurality of transmission methods including a transmission method to employ non-orthogonal multiple access (NOMA) and multiple-user multiple-input and multiple-output (MU-MIMO), and a second transmission mode, which groups a plurality of transmission methods including a transmission method to employ this NOMA and open-loop transmit diversity, and transmits a downlink signal for this user terminal based on the configured transmission mode.