We propose a systematic method for creating constellations of unitary space–time signals for multiple-antenna communication links. Unitary space–time signals, which are orthonormal in time across the antennas, have been shown to be well-tailored to a Rayleigh fading channel where neither the transmitter nor the receiver knows the fading coefficients. The signals can achieve low probability of e...

In this study, we analyze the environmental efficiency performance and its determinants of 29 manufacturing industries in China from 2006 to 2011 by employing a two-stage DEA (data envelopment analysis)-Tobit model. For providing comparative and robust evidence, the 29 manufacturing industries are classified into three groups based on the pollution intensity. In the first stage, a SBM (slacks-b...

With the emergence of a global economy, e-commerce is becoming strong catalyst to expand business activities and build an active customer base. It not very surprising see revolutionary way in which has helped industry. The integration information communication totally changed relationship between organizations, consumers those who act as mediators organizations consumers. use technology only en...

the study is based on covid19 effect small scale industries in ernakulam district , kerala. The aims at like food processing, textiles, furniture making, importing etc.