Abstract— This paper investigates different diversity concepts for OFDM systems. These are space frequency block codes (SFBC) and code division multiplexing (CDM). The performance of both and of combinations of both is compared for coded OFDM systems in a Rayleigh fading channel. The SFBCs and CDM applied in this paper have in common that they have no rate loss and thus do not decrease the band...

In this paper, the potential of orthogonal frequencydivision multiplexing-code-division multiplexing (OFDM-CDM) combined with the pre-equalization is investigated. The codedivision multiplexing (CDM) component within an orthogonal frequency-division multiplexing (OFDM) system enables additional diversity in frequencyand time-selective mobile radio channels. While, by applying pre-equalization a...

A gamma-ray halo in a nearby starburst galaxy NGC 253 was found by the CANGAROO-II Imaging Atmospheric Cherenkov Telescope (IACT). By fitting the energy spectrum with expected curves from Cold Dark Matter (CDM) annihilations, we constrain the CDM-annihilation rate in the halo of NGC 253. Upper limits for the CDM density were obtained in the wide mass range between 0.5 and 50 TeV. Although these...

Cold Dark Matter (CDM) has become the standard modern theory of cosmological structure formation. Its predictions appear to be in good agreement with data on large scales, and it naturally accounts for many properties of galaxies. But despite its many successes, there has been concern about CDM on small scales because of the possible contradiction between the linearly rising rotation curves obs...

The overall objective of this work is to apply GIS-based cost distance modeling (CDM) to site catchment modeling and analysis of prehistoric (Solutrean) sites in Andalusia. The implementation of a GIS-method for slope-based CDM was explained in detail, so that it can be replicated easily in future studies. Additional cost components, vegetation and stream networks, were included in the method. ...

Cold Dark Matter (CDM) has become the standard modern theory of cosmological structure formation. Its predictions appear to be in good agreement with data on large scales, and it naturally accounts for many properties of galaxies. But despite its many successes, there has been concern about CDM on small scales because of the possible contradiction between the linearly rising rotation curves obs...

We present a semi-analytical model to test the hypothesis that Lyα QSO absorption lines originate in gaseous halos produced by multiple supernova explosions occurring in Pop III objects in a CDM cosmological scenario hoping to assess the validity of CDM models and/or constrain their parameters. The preliminary results indicate that the range of NHI , redshift distribution and metallicity of clo...

There are three multiplexing schemes for Multi-Input MultiOutput (MIMO) channel sounder Time-division multiplexing (TDM), Code-division multiplexing (CDM) and Frequencydivision multiplexing (FDM). The purpose of this paper is comparison overview of multiplexing schemes for MIMO channel sounder. In this paper TDM, FDM and CDM techniques for MIMO channel sounding are considered. TDM, FDM and CDM ...