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.
We propose a novel regenerator site selection scheme for nonlinear impairment-aware elastic optical networks. The proposed scheme reduces bandwidth use by up to 40% in a realistic network by employing only 6 regenerator sites.
We transmit CM DP-16QAM signals at 4.88 b/s/Hz SE in C+L band EDFAs. We demonstrate nonlinearity noise mitigation by MAP-LMS equalizer. We show 2 dB error-correction margin improvement over DP-8QAM after 6,673 km transmission.
Real-time transmission with 26-GBaud PAM-4 as a promising modulation format for data-center interconnects with operation in C-band is evaluated. For an OSNR penalty below 2 dB a dispersion tolerance of up to 10 km of SSMF is achieved.
The RAN architecture splitting BS functions within PHY layer is prototyped and evaluated to confirm its validity. Experiments show that mobile fronthaul optical bandwidth is reduced by 90% compared to conventional C-RAN maintaining wireless performance.
We apply DBP to an experimental WDM system where multisubcarrier transmission provides a 12% reach gain vs. single-carrier. DBP provides further gain for both single- and multisubcarrier systems but significantly underperforms ideal theoretical predictions.
We investigate Nyquist spectral shaping using two-channel-interleaved DAC with zero-order holding for Nyquist-WDM 64QAM systems, which requires FIR filter with 57 taps, bandwidth of 0.4–0.6 times of the symbol rate, and DAC resolution >7 bits.
It is well known that the time-of-flight ranging performance is heavy influenced by multipath propagation within a radio environment. This holds in particular in dense multipath channels as encountered in indoor scenarios. The signal bandwidth has a tremendous influence on this effect, as it determines whether the time resolution is sufficient to resolve the useful line-of-sight (LOS) signal component...
The IEEE 802.16m based broadband wireless access is a promising technology to provide high speed and wide coverage communications for wireless users. However, how to achieve the desired utilization of the radio frequency bandwidth resource in such networks is an open issue as it covers the radio channel capacity exploitation, channel transmission bandwidth utilization optimization and resource utilization...
Relay enabled high speed wireless access, based on the IEEE 802.16j standard, is emerging as an attractive technology to realize the next generation broadband wireless metropolitan area networks. However, the link schedule associated with the traffic transmission, which has not specified and remained as an unsolved issue in such networks. In this respect, we construct a high efficient link schedule...
The energy efficiency of underwater acoustic carrier aggregation in Orthogonal Frequency Division Multiplexing (OFDM) systems is studied and an energy-efficient aggregation bandwidth selection method is proposed. Via simulations it is found that (i) the aggregation bandwidth has an optimal value maximizing the energy efficiency, (ii) this optimal aggregation bandwidth decreases with increasing distance,...
In the coexistence scenario of NB-IoT and LTE system, several factors affect the evaluating indicators of system performance. Considering the narrow bandwidth character of NB-IoT system, the simulation result would be over-optimistic if the evaluation method about ACLR and ACS in coexistence study of LTE system is still used. In this paper, a new evaluation method about ACLR and ACS is proposed aimed...
Next-generation cellular networks require new flexible backhaul technologies. Directed mmWave links with high order modulation can play an important role in cellular backhaul networks. To facilitate the research on such systems, a directional 60 GHz link using complex sub-sampling with a sampling bandwidth of up to 1.8 GHz is presented. The 60 GHz link is fully based on commercially available components...
Millimeter wave (mmWave) spectrum bands have been proposed for commercial wireless communications to relieve the spectrum crunch in the microwave band. The mmWave bands are being vigorously pursued for multiple gigabit data transmission. In this paper, channel models for line-of-sight (LOS) and non-line-ofsight (NLOS) links for specific mmWave frequency bands are presented and then used in the evaluation...
In the underwater communication, satellite communication, secure communication and other channels, the channel bandwidth is narrow and the channel condition is relatively poor. Therefore, higher quality and lower rate speech coding is needed. In order to improve the synthetic speech quality and save channel bandwidth, voice activity detection (VAD) technique is introduced to Mixed Excitation Linear...
Due to the upsurge of context-aware and proximity aware applications, device-to-device (D2D) enabled mobile cloud (MC) emerges as next step towards future 5G system. There are many applications for such MC based architecture but mobile data offloading is one of the most prominent one especially for ultra dense wireless networks. The proposed system exploits the short range links to establish a cluster...
Today's mobile radio systems deploy reference signals which can be used or which are even dedicated for signal propagation delay-based mobile terminal positioning. Usually, the signal power of such reference signals is uniformly distributed over the available spectrum. It is known from estimation theory that such a uniform power distribution of reference signals is not optimal for signal propagation...
Beamforming can spatially filter out a jamming signal and effectively obtain the desired directional gain. However, due to side-lobe, blunt beam of main-lobe, fault adaptation, and so forth, a targeted signal can be leaked to a reactive jammer. By sensing the leaked signal power, the reactive jammer concentrates its own power to the frequency band of the targeted signal. To solve this problem, we...
In case of wideband communications the analog-to-digital converter becomes a power consumption implementation bottleneck. Alternatively, transmission schemes based on coarse (1-bit) quantization and oversampling at the receiver can be beneficial. In this regard, information is conveyed in the zero-crossings. However, in presence of spectral constraints the waveform design becomes a challenge. In this...
Bandwidth and power are the major radio resources of a wireless communication system. Designing an efficient wireless communication system requires trade-off between these resources. In this context, definitions of radio resource efficiencies are given in terms of bandwidth efficiency, bit/s/Hz, and power efficiency, bit/Thermal Noise Energy Unit, for an arbitrary communication system. These efficiencies...
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.