Showing papers by "Rapeepat Ratasuk published in 2013"

Millimeter Wave Access Architecture with Cluster of Access Points

Abstract: The exemplary embodiments of the invention provide at least a method and an apparatus to determine a beacon signal for a network node, where the network node is configured to connect with a cluster of access points in a wireless communication network, and where the beacon signal identifies the cluster; and send the beacon signal towards the wireless communication network. Further, the exemplary embodiments of the invention provide at least a method and an apparatus to determine a dominant access point of a cluster of access points based on signaling from at least one access point associated with the cluster of access points; and in response to the determining, direct communications towards the dominant access point of the cluster of access points.

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.

Moving Towards Mmwave-Based Beyond-4G (B-4G) Technology

Abstract: Availability of large untapped spectrum resources in the millimeter wave (Mmwave) band is suitable for providing a gigabit experience with true local feel using high capacity small cells. Unlike traditional cellular systems, millimeter wave transmissions do not benefit from diffraction and dispersion making it difficult for them to propagate around obstacles thus resulting in higher shadowing loss. They also have less favorable link budgets due to lower power amplifier (PA) output powers and greater pathloss at these higher frequencies. Also, current costs of the Mmwave circuits are higher, but the costs will become much lower when the technology becomes mainstream. One advantage of millimeter wave, however, is that the smaller wavelengths allow for the fabrication of antenna arrays having a much higher number of antenna elements in a much smaller area than is typical at microwave bands. In this article, we outline a framework for Beyond-4G (B-4G) local area network in the millimeter wave band for both access and backhaul including air-interface, antenna-arrays and IC technology. It is shown that Mmwave B-4G small cell technology can provide peak and cell edge rates greater than 10 Gbps and 100 Mbps respectively with latency less than 1msec for local area network.

Wireless communication scheduling on shared spectra

Abstract: A method includes scheduling, by a base station configured to service a cell within a cellular communication network, multiple grants to an apparatus in a coverage area of the cell. Each of the scheduled multiple grants includes time-frequency resources in at least one shared spectrum that is to be used by the apparatus to attempt to communicate. Each of the scheduled multiple grants differs from others of the scheduled multiple grants in one or both of time or frequency. The method includes sending indications of the scheduled multiple grants. Another method includes receiving, at the apparatus in the cell, indications of the multiple grants and attempting by the apparatus to communicate using one or more of the multiple grants. Apparatus, computer programs, and program products are also disclosed.

Carrier aggregation in heterogeneous cellular networks

Abstract: Heterogeneous networks (HetNets) and carrier aggregation (CA) are two distinct features of next-generation cellular networks. Small cells in HetNets are vital for data off-loading and can significantly improve area and cell edge spectral efficiency compared to using just macrocells. CA further increases the transmission bandwidth and thus network capacity by aggregating multiple component carriers on the physical layer. In this paper, we propose a tractable multi-band multi-tier model to study multi-flow CA in HetNets, where base station positions in each tier follow an independent Poisson point process. Our model incorporates an appropriate notion of load which allows the study of the impact of biasing on HetNet performance. For a typical HetNet consisting of two tiers, macro cells and small cells, and two bands, 800MHz band and 2.4GHz band, we observe that the gain (in terms of UE ergodic rate) is about 35% to 40% if the small cells adopt optimal biasing factor compared to the case without biasing. Our model also incorporates the impact of band deployment. For the typical HetNet described, our study suggests that deploying the 800MHz band and 2.4GHz band in both the macro and small cells helps the HetNet best exploit the CA feature.

Performance of Low-Cost LTE Devices for Advanced Metering Infrastructure

Abstract: Machine type communications (MTC) is defined as data communication among devices without the need for human interaction With the decommissioning of legacy cellular systems, migration of MTC devices to LTE is under investigation by many operators It is desirable that the cost of LTE MTC devices is similar to that of existing GSM devices Several cost reduction techniques have been studied This paper summarizes cost reduction techniques for MTC devices and examines system impacts from such devices being introduced in LTE Performance is evaluated for the Advanced Metering Infrastructure used in smart grid It is seen that LTE offers significant capacity for smart metering even with low-cost devices For a system with 10 MHz bandwidth, approximately 2% of the system resource is required to support AMI in an urban deployment scenario

Method and apparatus for moderated access to shared radio spectrum resources

Abstract: Certain embodiments may relate to communication systems, for example wireless communication systems. For example, wireless communication networks may benefit from moderated access to shared radio spectrum resources. A method may include receiving an identification of radio spectrum resources corresponding to at least one incumbent and available for sharing. The method may also include sharing the radio spectrum resources to at least one radio access network operator. The method may further include maintaining a priority for the at least one incumbent over the at least one operator with respect to the radio spectrum resources.

Compact dci for machine type communications

Abstract: A method for coverage enhancement is described. The method includes determining a DCI assignment for a communications device experiencing limited coverage. A DCI assignment includes a plurality of configuration fields. Selecting an indication of the DCI assignment is included in the method. The indication of the DCI assignment uses fewer resources than the DCI assignment. The method also includes sending the indication of the DCI assignment to the communications device. The communications device receives the indication of a DCI assignment. The method also includes determining, by the communications device, the DCI assignment for the communications device based at least in part on the indication of the DCI assignment.

Synchronization of a device in communications

Abstract: A method for synchronizing communication devices comprises receiving, in a communication device (102), a first synchronization signal transmitted from a network apparatus (101). Based on the first synchronization signal, communication device (102) performs a coarse synchronization process. Based on the coarse synchronization process, the communications device (102) transmits a scheduling request message to the network apparatus (101). The communication device (102) receives (306), from the network apparatus (101), a second synchronization signal, together with a scheduling grant, at a predetermined time window with reference to the scheduling request, and transmits (307) data from the communication device (102) to the network apparatus (101), based on the scheduling grant.

Compact downlink control information for machine type communications

Abstract: A method for coverage enhancement is described. The method includes determining a DCI assignment for a communications device experiencing limited coverage. A DCI assignment includes a plurality of configuration fields. Selecting an indication of the DCI assignment is included in the method. The indication of the DCI assignment uses fewer resources than the DCI assignment. The method also includes sending the indication of the DCI assignment to the communications device. The communications device receives the indication of a DCI assignment. The method also includes determining, by the communications device, the DCI assignment for the communications device based at least in part on the indication of the DCI assignment.

Shared Access of Uplink Carrier

Abstract: A method includes configuring user equipment to support use of one or more carriers for authorized shared access. The configuring is performed to emphasize use of a first set of a plurality of carriers over use of a second set of the plurality of carriers. The second set comprises the one or more carriers for authorized shared access. The method also includes communicating with the user equipment using the first and second sets of carriers. Apparatus, computer programs, and program products are also disclosed.

Half duplex scheduling

Abstract: Systems and techniques are described for scheduling communication by half-duplex devices. One or more half-duplex devices informs a base station that it is capable only of half-duplex operation. For each such device, the base station configures a transmit/receive pattern comprising sequences of uplink and downlink subframes and applies the pattern to the device. The half-duplex device may receive during a downlink subframe and may transmit during an uplink subframe. Uplink and downlink subframes within a pattern are separated by an offset based at least in part on a number of hybrid automatic repeat request processes.