We investigate a combination of linear scalable space-time block codes with OFDM and present a systematic code design. This approach leads to space-frequency coded MIMO-OFDM with a variable tradeoff between improving link reliability (by using diversity techniques) and increasing data rate (using spatial multiplexing). The proposed coding scheme achieves spatial, temporal and frequency diversit...

Optical cavities containing a negative dispersion medium have been proposed as a means of improving the sensitivity of laser interferometric gravitational wave detectors through the creation of white-light signal recycling cavities. Here we demonstrate that negative dispersion can be realized using an optomechanical cavity pumped by a blue detuned doublet. We used an 85-mm cavity with an intrac...

Linear dispersion codes (LDCs) are an attractive tool for attaining spatial diversity in OFDM systems with multiple transmit antennas. To reach the potential gains, in each situation, the selection of a proper set of codes depends, in general, on the existence of a reliable feedback channel. We propose LDCs for multiple-input multiple-output (MIMO) channels with a fixed amount of feedback. The ...

We reconsider the problem of producing fair and accurate tariffs based on aggregated insurance data giving numbers of claims and total costs for the claims. Jorgensen and de Souza (Scand. Actuarial J., 1994) assumed Poisson arrival of claims and gamma distributed costs for individual claims. Jorgensen and de Souza (1994) directly modelled the risk or expected cost of claims per insured unit, p ...

In the present study, analytical solutions are obtained for two-dimensional advection dispersion equation for conservative solute transport in a semi-infinite heterogeneous porous medium with pulse type input point source of uniform nature. The change in dispersion parameter due to heterogeneity is considered as linear multiple of spatially dependent function and seepage velocity whereas seepag...