Filtreler

2002 - 20083
Filtreleri Sıfırla

Ayarlar

Erişim Hakkı: info:eu-repo/semantics/closedAccess × Konu: Channel capacity ×

Arama Sonuçları

Listeleniyor 1 - 3 / 3
  • Küçük Resim
    Yayın
    On the extraction of the channel allocation information in spectrum pooling systems
    (IEEE, 2007-04) Öner, Mustafa Mengüç; Jondral, Friedrich K.
    The spectrum pooling strategy allows a license owner to share a part of his licensed spectrum with a secondary wireless system (the rental system, RS) during its idle times. The coexistence of two mobile systems on the same frequency band poses many new challenges, one of which is the reliable extraction of the channel allocation information (CAI), i.e. the channel occupation of the licensed system (LS). This paper presents a strategy for the extraction of the CAI based on exploiting the distinct cyclostationary characteristics of the LS and RS signals and demonstrates, via simulations, its application on a specific spectrum pooling scenario, where the LS is a GSM network and the RS is an OFDM based WLAN system.
  • Küçük Resim
    Yayın
    Blind channel estimation for space-time coding systems with Baum-Welch algorithm
    (IEEE, 2002) Çırpan, Hakan Ali; Panayırcı, Erdal
    In recent years, space-time coding is proposed to provide significant capacity gains over the traditional communication systems in fading wireless channels. In this paper, we consider the problem of blind estimation of the channel parameters along with space-time coded signals. Our proposed approach exploits the finite alphabet property of the space-time coded signals and is based on the unconditional signal model by treating the information sequence as stochastic I.I.D. sequences. The iterative Baum-Welch algorithm is then adapted to solve resulting unconditional ML optimization cost function. Finally, some simulation results are presented.
  • Küçük Resim
    Yayın
    On the spectral correlation of UWB impulse radio signals
    (IEEE-INST Electrical Electronics Engineers Inc, 2008-10) Öner, Mustafa Mengüç
    Cyclostationarity is an inherent characteristic of many communication signals, which can be exploited for performing various signal processing tasks. Determining the cyclic statistics of a signal of interest is often necessary in the design of signal processing systems exploiting this cyclostationary behaviour. This work investigates the second order cyclic statistics of various signalling schemes employed in ultra wideband impulse radio systems. Analytical expressions are derived for the cyclic autocorrelation and spectral correlation density functions.