Serwis Infona wykorzystuje pliki cookies (ciasteczka). Są to wartości tekstowe, zapamiętywane przez przeglądarkę na urządzeniu użytkownika. Nasz serwis ma dostęp do tych wartości oraz wykorzystuje je do zapamiętania danych dotyczących użytkownika, takich jak np. ustawienia (typu widok ekranu, wybór języka interfejsu), zapamiętanie zalogowania. Korzystanie z serwisu Infona oznacza zgodę na zapis informacji i ich wykorzystanie dla celów korzytania z serwisu. Więcej informacji można znaleźć w Polityce prywatności oraz Regulaminie serwisu. Zamknięcie tego okienka potwierdza zapoznanie się z informacją o plikach cookies, akceptację polityki prywatności i regulaminu oraz sposobu wykorzystywania plików cookies w serwisie. Możesz zmienić ustawienia obsługi cookies w swojej przeglądarce.
Full-duplex radio has potential to double spectral efficiency by simultaneously transmitting and receiving signals in the same frequency band, but at the expense of additional hardware and power consumption for self-interference cancellation. Hence, the deployment of a full-duplex cellular network can be realized by employing full-duplex functionality only at an eNodeB, which is supposed to have sufficient...
In this paper, we analyze temporal and spatial distribution characteristics of multipath components considering for device-to-device (D2D) communications scenarios in urban very high-rise environments. Using the 3.7GHz wideband channel sounder and uniform circular array antennas, a channel measurement campaign has been performed at Gangnam of Seoul in Korea which the place very high-rise buildings...
In this paper we derive a non-line-of-sight (NLOS) path loss model between low-height terminals in rectangular street grid environments. With the Uniform Geometrical Theory of Diffraction, the path loss due to diffraction and scattering at corner edges is calculated for 1-Turn NLOS and 2-Turn NLOS links. In particular, we consider the case that 2-Turn NLOS links have multiple propagation route paths...
In this paper, we focus on multipath channel characteristics of low-height antenna links for mobile to mobile communications in urban street canyon environments. We present a wideband MIMO channel sounder and antennas used to measure multipath channel characteristics in the 3.7GHz frequency band and the result of calibration test to evaluate a system performance before field measurement. We carried...
In this paper, we investigate the characteristics of spatial correlation coefficient (SCC) of low-height links in urban street grid environments. The SCC is calculated from measurement data collected in Seoul city with a 100MHz wideband channel sounder at the center frequency of 3.7GHz. To emulate low-height D2D links, we installed TX and RX antennas at the height of 1.9 m above the ground. The SCC...
This paper presents line-of-sight (LoS) path loss characteristics for low-antenna links in urban street environments to account for propagation channels in mobile-to-mobile direct communications. The key variables, from the perspective of horizontal and vertical planes of such environments, are street width and surrounding building height. In this paper, we investigate the effects of the environmental...
In this paper, we focus on multipath channel characteristics of low-height antenna links for mobile to mobile communications in urban street grid environments. We present a wideband MIMO channel sounder and antennas used to measure multipath channel characteristics at 3.7GHz frequency band and the result of calibration test to evaluate a system performance before field measurement. We carried out...
Dynamic spectrum access (DSA) based on interruptible spectrum leasing allows secondary users (SUs) to lease a licensed, but idle, spectrum that is owned by primary users (PUs) on condition that the PUs preempt the access to the leased spectrum. This paper considers a DSA scenario where the SUs opportunistically use the primary spectrum in addition to their own band and the PUs use their own band regardless...
This paper considers a dynamic spectrum allocation (DSA) model that a spectrum broker (SB) coordinates the allocation of the spectrum with the regional license inside the region of responsibility. It has a potential to leverage the spectrum utilization but requires a sophisticated approach to manage the allocation-dependent interference effect. Thus, the SB is responsible to manage the wireless interference...
In this paper, we introduce dynamic spectrum access/cognitive radio activities in Korea. In the past, spectrum management in Korea was command and control with exclusive usage rights and small portions of spectrum commons bands. With the development of the radio technologies, Korea government, KCC(Korea Communications Commission), has been adopting new spectrum policies based on dynamic spectrum access...
Chaotic oscillators can generate wide-band signals and the spectrum characteristics of the signals are not changed by switching the output power of the oscillators. If communication systems could be implemented using a chaotic oscillator, the communication system need not a local oscillator, a mixer, IF amp. And so forth which are needed in conventional transceivers. Therefore the configuration of...
Podaj zakres dat dla filtrowania wyświetlonych wyników. Możesz podać datę początkową, końcową lub obie daty. Daty możesz wpisać ręcznie lub wybrać za pomocą kalendarza.