The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Direct device-to-device (D2D) communication is considered to be part of fifth generation (5G) networks, while embodying vehicle-to- anything (V2X) communication into the recently defined Long Term Evolution (LTE) sidelink is already on the way. Coexistence of in-band D2D and cellular transmissions requires time synchronization between multiple links to prevent from interference and avoid using longer...
Location-Based services are gaining momentum as an important advancement in context aware services. That is, empowering users to identify potential services in their current space, and the prospect for services that are able to target local users, are pushing interest in research and industry alike. This paper explores the use of non-audible sound as a communication medium to tag and access location...
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...
In this paper, we look at reusing existing packet-based network (e.g. Ethernet) to possibly decrease deployment costs of fronthaul Cloud Radio Access Network (C-RAN) network and cost of Baseband Unit (BBU) resources. The challenge of this solution is that it requires mobile traffic (until now transmitted over synchronous protocols) to traverse the asynchronous Ethernet without losing synchronization...
Synchronization in transport networks was a hot topic for telecom in early 90's with the advent of SDH, replacing PDH. When packet networks and the Internet began to spread, it subsided for some years, until mobile technologies evolved from TDM (2G) to packets (3G, 4G). Nowadays the transport of frequency and time over transport networks is one of the most debated topics both in the industry and within...
We propose a time and frequency synchronized λ-tunable WDM/TDM-PON with a synchronization method using timestamps. We clarify requirements of synchronization accuracy for mobile backhaul networks numerically and confirm its feasibility experimentally.
This paper presents a novel High-speed aeronautical communication technique based on orthogonal frequency division multiplexing (OFDM) and practical implementation of it. We described several blocks in the OFDM system to establish the specifications for the receiver which is in the airplane equipment. Especially, the synchronization block and channel estimation block play a key role among the receiving...
In the lately released Chinese mobile multimedia broadcasting standard CMMB, cyclic-prefix based OFDM technique has been adopted. Traditional timing synchronization for this system requires a correlator to correlate the last Ng samples of the received OFDM symbol with their copies ahead, and at least N (the length of OFDM symbol) data and Ng correlation results have to be stored for implementation,...
In this paper, we present coarse synchronization algorithms for OFDM systems, specifically applied with mobile WiMAX transmissions. We consider computationally efficient synchronization algorithms, which are applicable also without full knowledge of the properties of the transmitted signal at the receiver. Although the proposed algorithms are considered for a mobile WiMAX system, their application...
This paper presents a BFSK demodulation method using discrete short-time Fourier transform (DSTFT). The method discusses the BFSK signal in time-frequency domain, which is different from conventional demodulation methods. The principle of demodulation and a new code synchronization algorithm are given in the paper, different window functions are tried during the simulation, which bring different demodulated...
Class D amplifiers are becoming the most feasible solution for embedded audio application. However, distortions due to the non-linear nature of switching stage are the main drawback for this amplifier topology. This paper discusses the design and implementation of high fidelity audio class D using sliding mode control scheme. This design method proves to be a cost effective solution for industrial...
In the high-speed wireless communication, by the frequency difference impact, it took longer time to capture the carrier and to establish the symbol synchronization within the demodulation. Given the characteristics of pi/4 -DQPSK modulation and frequency-hopping communication, which were widely used in the wireless communication, the algorithm of the rapid signal capture and synchronization recognition...
Correlative minimum shift keying (MSK), a second order polynomial modulation scheme known as tamed frequency modulation (TFM), is a constant envelope type of modulation with a perfect peak to average power ratio (PAPR), besides the property of low out of band power. We apply the linearized TFM to the single carrier transmission with frequency domain equalization (SC/FDE) concept. We then obtain a...
While two-dimensional (2-D) orthogonal variable spreading factor (OVSF) codes were proposed for multicarrier direct-sequence code-division multiple-access (MC/DS-CDMA) systems in order to eliminate multiple-access interference, the number of orthogonal sequences (or code cardinality) was restricted by the number of carrier frequencies. Non-orthogonal 2-D frequency-time-spreading (FTS) codes were then...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.