Optimization Info Rate Using APSK Modulation Scheme for Delivery GSM ABIS over Satellite Communications

We consider the evolution of a GSM-based indoor corporate network, where base transceiver stations (BTS) are IP end-points of the local area network (LAN). Multiplexing capabilities of real time protocol (RTP) payloads are exploited in order to transport efficiently TRAU (transcoding and rate adaptation unit) frames between each BTS and the BSC (base station controller)/access node. In this context, two RTP connections are used to transmit downlink TRAU frames to both current BTS and candidate BTS during handover execution, thus preventing typical loss of voice frames during this phase. This contributes to improving the quality of service (QoS) for voice communications in the selected environment. Signaling issues and assignments of resources to individual connections within a single RTP/UDP/IP connection in the described environment are also addressed. The proposed architecture also offers advantages for implementing tandem free operation (TFO) in a local environment.

Street characteristics and traffic factors determining road users' exposure to black carbon

We propose an enhancement to the parametric-decomposition method for calculating approximate steady-state performance measures of open queueing networks with non-Poisson arrival processes and nonexponential service-time distributions. Instead of using a variability parameter ca2 for each arrival process, we suggest using a variability function ca2ρ, 0 < ρ < 1, for each arrival process i.e, the variability parameter should be regarded as a function of the traffic intensity ρ of a queue to which the arrival process might go. Variability functions provide a convenient representation of different levels of variability in different time scales for arrival processes that are not nearly renewal processes. Variability functions enable the approximations to account for long-range effects in queueing networks that cannot be addressed by variability parameters. For example, the variability functions provide a way to address the heavy-traffic bottleneck phenomenon, in which exceptional variability (either high or low) in the input has little impact in a series of queues with low-to-moderate traffic intensities, and then has a big impact when it reaches a later queue with a relatively high traffic intensity. The variability functions also enable the approximations to characterize irregular periodic deterministic external arrival processes in a reasonable way; i.e., if there are no batches, then ca2ρ should be 0 for ρ near 0 or 1, but ca2ρ can assume arbitrarily large values for appropriate intermediate ρ. We present a full network algorithm with variability functions, showing that the idea is implementable. We also show how simulations of single queues can be effectively exploited to determine variability functions for difficult external arrival processes.

Hand over is one of the most important function of a cellular network. Hand success rate (HOSR) improvement is an important optimization activity of a GSM network (NW). Cellular operators adapt different approaches like locations area updates at cell boundaries and optimization of adjacencies, threshold parameters etc. for HOSR improvement. Cellular operators don't consider network synchronization as an important issue for call handover success rate. This article presents an investigation and analysis carried out on a live BSC (Base station controller) of a TDM GSM network in India deployed in Madhya Pradesh state to demonstrate how frequency drift of a BSC, resulting from poor synchronization can degrade HOSR. This article also presents the correlation between DAC word value (frequency drift) of a BSC and HOSR, and how DAC word value analysis can be used to assess HOSR degradation. In addition various methods for the performance evaluation of synchronization network, like clock quality, synchronization failure alarms, and clock frequency drift etc. and different issues and requirements with regard to synchronization of cellular network are presented.

For code-division multiple-access (CDMA) cellular communications synchronous operation offers significant advantages over asynchronous operation. This feature has been already included in second-generation systems, such as the CdmaOne based on the IS-95 standard. Nonetheless, synchronous operation does not seem to be assessed as a basic system option for third-generation systems. This is mainly due to the contrasted choice of having global positioning system (GPS) receivers located at any of the base transceiver stations (BTSs) to perform station synchronization. However, the existing CdmaOne interface permits time transfer between the various BTSs and a simple time difference measurement technique can provide an internal, network-based means for time synchronization of base stations clocks. This paper considers a previously proposed approach based on the pilot strength measurements message delivered by every mobile station (MS), combined with round trip delay measurements that BTSs perform on the MS transmissions. We consider some possible algorithms to reduce time misalignments, and continuously phase-lock the clocks at different BTSs. Having developed an appropriate analytical/simulation approach, in the environment of a CDMA network, the paper evaluates and compares the performance of two suitable centralized architecture configurations, i.e., master-slave synchronization (MSS) and mutual synchronization (MUS). Both network architectures turn out to be applicable and provide suitable timing performance. Finally, the paper provides a preliminary discussion on some related issues, such as GPS avoidance, synchronization of BTSs inside buildings, tunnels, and subways and hybrid MSS/MUS synchronization network architectures.

Guest editorial IJSCN special issue on 3GPP NTN standards for future satellite communications

A mathematical matrix formalism which combines network management system (NMS) statistics from Cosmote GSM land mobile radio network and MOS measurements derived from drive tests are used, in order to extract a derivative MOS key performance indicator. Initially, the calculation is performed in a base station controller (BSC) area and then base transceiver stations (BTS) MOS distribution patterns are examined for different speech encodings. Examples of speech encoding effectiveness evaluation are performed using the previous speech encoding distribution patterns. Moreover, the effect of mobile station (MS) technology on different speech encodings is pointed out. Ultimately, different speech encodings are compared using quality and speech codec distribution patterns.

Geographic Information System (GIS) is an effective medium to identify the location of cellular operator telecommunication towers in finding locations that are not covered by cellular operator telecommunication tower signals and supports the placement of new cellular operator telecommunication towers. Based on this, the problems that arise are difficulties in obtaining information on the location of telecommunication towers for cellular operators, differences in distances that can be traveled, the difficulty of the BTS (Base Transceiver Station) Development and Control Supervisory Board knowing how many telecommunication towers from each provider in Bandar Lampung. and the absence of a system to identify the location of cellular operator telecommunication towers in Bandar Lampung digitally. Based on this, the researcher proposes a Geographic information system for mapping tower bases transceiver stations (BTS). From the results of the research that has been done, the Geographic Information System (GIS) can identify the tower location points. With this system, it is hoped that this system can be used as a reference for the BTS Development and Control Supervisory Agency in identifying the location of cellular operator telecommunication towers in Bandar Lampung as well as being a reference for the BTS (Base Transceiver Station) Development and Control Supervisor in the construction and placement of new cellular operator telecommunication towers in Bandar Lampung. Bandar Lampung.

In this paper, the performance of peer-to-peer (P2P) file sharing service based-on flooding search algorithm is analyzed. We focus on six types of four-terminal four-router physical network, and investigate the impact of topology inconsistency and flooding search on the file retrieval performance. The analysis model is based on a two-layer queueing network in which both logical and physical topologies are taken into account, and the file search time and file transfer delay are analyzed. We observe from numerical examples that an overlay network with high node degree provides a small file search time for a low traffic intensity, while the performance of the high node-degree overlay network rapidly degrades with a high traffic intensity.

Traffic alternatives for harvesting soybean ( Glycine max L.): Effect on yields and soil under a direct sowing system

The research work was conducted to determine the concentration of Arsenic, Cupper, Strontum, and Zinc in some plant leaves (Dodoneae, Eucalyptus, Albizia Lebbeck) grown in different location in Kalar- Sulaymaneyah, Iraq to investigat contamination caused by traffic related pollutant. The samples were collected in (City Center, Industrial Area, Salih Agha village, and Garmian university campus). Concnetration of the selected elemnts were measured by inducively coupled plasma optical emission spectroscopy (ICP-OES) after wet digestion with acid mixture of (HNO3:H2O2). The mean concentration ranges of heavy metals in different plant leaves samples were: As = ND – 0.9; Cu =0.4 – 1.9; Sr =15 – 797.7 Zn = ND - 20 mg/Kg. The highest concentrations of different heavy metals were found in the samples collected from heavy traffic. The study revealed that the concnetration ranges of Sr and Zn in samples collected in higher traffic intensities were several times higher than those collected from lower traffic intensities compared to Cu and As which the increase in thier concnetration is slight.

The influence of heavy goods vehicle traffic on accidents on different types of Spanish interurban roads

Environmental pollution caused by heavy metals is an increasingly pressing ecological issue. One of the main sources of these pollutants is road transport. This study aimed to assess the impact of traffic intensity on heavy metal emissions using locally occurring vegetation as a natural indicator of environmental contamination. The research focused on a common and widely distributed plant species – dandelion (Taraxacum officinale) – analyzing its capacity to accumulate pollutants. Plant samples were collected from four different locations with varying levels of traffic: near a highway, urban roads, and a forest area used as a reference site. The plants differed visually depending on the collection site, indicating the influence of pollution on their physical condition. Laboratory analyses revealed that plants from the area with the highest traffic intensity contained approximately four times higher concentrations of selected heavy metals – including Cd, Fe, Mn, Pb and Zn – compared to samples from the forest site. These results demonstrated the ability of dandelions to accumulate heavy metals in their biomass show that local vegetation can serve as a simple, cost-effective, and non-invasive tool for environmental monitoring, supporting the planning of pollution mitigation efforts and soil phytoremediation strategies in urbanized and traffic-exposed areas.

The base station (BS) in the CDMA Mobile System (CMS) connects calls through the radio interface and is designed to provide mobile subscribers with high quality service in spite of mobile subscribers’ motions. The BS consists of multiple base station transceiver subsystems (BTSs), a base station controller (BSC) and a base station manager (BSM). This paper is concerned with the BSC and the BSM. The BSC is located between the BTSs and the mobile switching center (MSC) connected with the public network, and is responsible for controlling mobile calls from and to mobile subscribers via the BTSs. The BSM provides operator-interfaces per the BS and takes responsibility of operation and maintenance (OAM) of the BS. Design of the BSC is based on two module types: functional module and unit module. The functional module is used to support new services easily and the unit module to increase the system capacity economically. Both modular types are easily achieved by inserting the corresponding modules to the system. Particularly, in order to efficiently support the soft handover which is one of CDMA superior advantages, the BSC adopts a large high-speed packet switch connecting up to 512 BTSs, and thus mobile subscribers can be provided with soft handover in high probability. The BSM is based on a commercial workstation to support OAM functions efficiently and guarantee high reliability of the functions. The BSM uses graphical user interface (GUI) for efficient OAM functions of the BS.

Most of the models of road traffic flow at fixed-cycle controlled intersection assume stationary distributions and provide steady state results. The assumption that a constant number of vehicles can leave the system during the green phase is unrealistic in real life situations. A discrete time queuing model was developed to describe the operation of traffic flow at a road intersection with fixed-cycle signalized control and to account for the randomness in the number of vehicles that can leave the system. The results show the expected queue size in the system when the traffic is light and for abusy period, respectively. For the light period, when the traffic intensity is less than one, it takes a shorter green cycle time for vehicles to clear up than during high trafficintensity (the road junction is saturated). Increasing the number of cars that can leave the junction at the turn of the green phase reduces the number of cycle times before the queue is cleared.