We study the formation of B i lines in a grid of cool stellar model atmospheres without the assumption of local thermodynamic equilibrium (lte). The non-lte modelling includes the effect of other lines blending with the B i resonance lines. Except for the cases where the B i lines are very strong, the departures from lte relevant for the resonance lines can be described as an overionisation eff...

Long Term Evolution (LTE) was initially designed for a high data rates network. However, voice service is always a main service that brings a big benefit for mobile operators. Hence the deployment of Voice over LTE (VoLTE) is very essential and urgent. LTE network is a fully All-IP network, thus, the deployment of VoLTE is very complex, specially for guaranteeing of Quality of Service (QoS) to ...

Augmenting the LTE evolved NodeB with cloud resources offers a low-latency, resilient, and LTE-aware environment for offloading the Internet of Things (IoT) services and applications. By means of devices memory replication, the IoT applications deployed at an LTE integrated edge cloud can scale its computing and storage requirements to support different resource-intensive service offerings. Des...

Repeaters have been an attractive solution for mobile operators to upgrade their wireless networks at low cost and to extend network coverage effectively. Since the first LTE commercial deployment in 2009, many mobile operators have launched LTE networks by upgrading their 3G and legacy networks. Because all 3G frequency bands are shared with the frequency bands for LTE deployment and 3G mobile...

Korea has made a plan to transfer from analog television to Digital Television (DTV). Therefore, TV White Spaces (TVWS)are the unused TV broadcast channels which can be available for wireless communication systems. This paper assumes that DTV operates on Channel 34 and Long Term Evolution (LTE) is assumed that it uses Frequency Division Duplexing (FDD), and then upper 4 MHz of Channel 32 and ch...

LTE networks have been rapidly commercialized for 4G cellular communications systems in all over the world as well as Korea. Because many internet applications use TCP as their transport layer protocol, TCP throughput measurements and its performance improvements in LTE networks is very important. In this paper, we analyze the impact of “in-sequence delivery” in LTE link layer on TCP RTT increm...

Long Term Evolution (LTE) is the next step towards in the arena of 3G cellular wireless services. Expected in the 2008 time frame, it is a 3GPP standard which provides an uplink transmission rate of up to 50 megabits per second (Mbps) and a downlink transmission rate of up to 100 Mbps. LTE evolved from an early 3GPP wireless standard identified as Universal Mobile Telecommunication System (UMTS...

This paper presents low-level models of cellular LTE signals along with an architecture for a software-defined radio (SDR) that is capable of (1) extracting the essential parameters for navigation from the received LTE signals and (2) acquiring and tracking real LTE signals transmitted from multiple base stations. Moreover, a method for obtaining time-of-arrival (TOA) estimates that is highly r...

To avoid the foreseeable spectrum crunch, LTE operators have started to explore the option to directly use 5GHz unlicensed spectrum band being used by IEEE 802.11 (WiFi). However, as LTE is not designed with shared spectrum access in mind, there is a major issue of coexistence with WiFi networks. Current coexistence schemes to be deployed at the LTE-U BS create coexistence gaps only in one doma...