Balakrishnan Kannan

Learn More
A comprehensive statistical model is described for ultrawideband (UWB) propagation channels that is valid for a frequency range from 3-10 GHz. It is based on measurements and simulations in the following environments: residential indoor, office indoor, builtup outdoor, industrial indoor, farm environments, and body area networks. The model is independent of(More)
We present a statistical model for the characterization of ultra-wideband (UWB) channels for the outdoor office environment. The bandwidth is from 3-6 GHz and measurements are done for the line-of-sight (LOS) and non-line-of-sight (NLOS) cases. Small scale effects are modeled by the Saleh-Valenzuela (S-V) model with modifications on the ray arrival times(More)
Learning disability (LD) is a neurological condition that affects a child’s brain and impairs his ability to carry out one or many specific tasks. LD affects about 10% of children enrolled in schools. There is no cure for learning disabilities and they are lifelong. The problems of children with specific learning disabilities have been a cause of concern to(More)
In this letter, the influence of temporal and spatial diversities on the performance of ultra-wideband time-hopping pulse-position modulated multiple-access impulse radio (IR) systems is analyzed. We investigate how an antenna array can be used at the receiver to improve the bit-error rate (BER) performance and can cope with the effects of multiple-access(More)
A new analytical method is introduced for the exact statistical modeling of multiple access interference (MAI), in time hopping pulse position modulation (TH-PPM) ultra wideband (UWB) systems. Based on this model the exact bit error rate (BER) is expressed in simple formulas. The proposed modeling of MAI considers complete asynchronism, and is also suitable(More)
Handwritten character recognition is always a frontier area of research in the field of pattern recognition and image processing and there is a large demand for OCR on hand written documents. Even though, sufficient studies have performed in foreign scripts like Chinese, Japanese and Arabic characters, only a very few work can be traced for handwritten(More)
© 2016 Journal of ophthalmic and Vision research | published by Wolters KluWer medKnoW Dear Editor, We report a 15-year-old girl who presented to us with a history of progressive weakness of both upper and lower limbs for 2 days before. On examination, the power of lower and upper limbs were 2/5 and 4/5, respectively. She had decreased tone and areflexic(More)
Ultrawideband (UWB) technology is characterized by transmitting extremely short duration radio impulses. To improve its multiple-access capability, the UWB technology can be combined with traditional spread-spectrum techniques. This paper demonstrates the influence of spatial and temporal diversities on the performance of direct-sequence (DS) UWB(More)