Mainak Mukhopadhyay

Augmentation of Anti-Jam GPS System Using Smart Antenna with a Simple DOA Estimation Algorithm

Smart Antenna system analysis presented with multipath and null constraint for reducing interference and efficient use of spectrum with the help of LMS algorithm for GPS (Global Positioning System) System. A new simple DOA (Direction of Arrival) estimation method by rotation of antenna plane proposed. Simulated Result obtained using MATLABTM.

Accessibility of Enzymatically Delignified Bambusa bambos for Efficient Hydrolysis at Minimum Cellulase Loading: An Optimization Study

In the present investigation, Bambusa bambos was used for optimization of enzymatic pretreatment and saccharification. Maximum enzymatic delignification achieved was 84%, after 8 h of incubation time. Highest reducing sugar yield from enzyme-pretreated Bambusa bambos was 818.01 mg/g dry substrate after 8 h of incubation time at a low cellulase loading (endoglucanase, β-glucosidase, exoglucanase, and xylanase were 1.63 IU/mL, 1.28 IU/mL, 0.08 IU/mL, and 47.93 IU/mL, respectively). Enzyme-treated substrate of Bambusa bambos was characterized by analytical techniques such as Fourier transformed infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The FTIR spectrum showed that the absorption peaks of several functional groups were decreased after enzymatic pretreatment. XRD analysis indicated that cellulose crystallinity of enzyme-treated samples was increased due to the removal of amorphous lignin and hemicelluloses. SEM image showed that surface structure of Bambusa bambos was distorted after enzymatic pretreatment.

Incorporation of Anti-Jamming Techniques in a GPS Receiver

GPS guidance uses low power signals from satellites which are 11000 NMI away. The satellite transmitter power is modest nearly 10 W orders of magnitude. Neither satellite nor receivers have the luxury of very high antenna gain since both entities have significant field of view requirements. These factors result in a very low power density incident on a GPS receiver antenna. The signal received is generally 165 dB down than the thermal noise level. Such signals are notoriously easy to jam either by intentional noise sources (Jammer) or unintentionally from harmonics of broadcasting stations or other out of band sources. Here in this paper we will show how a nulling antenna or controlled reception pattern antenna with adaptive spatial filtering technique efficiently mitigate the intentional and non intentional interferences.

Oleaginous Fungi: A Solution to Oil Crisis

Oleaginous fungi are known for microbial oil as they can accumulate intracellular lipid up to 70% under stress condition. Like vegetable oils, microbial oils component is TAG, composed of C16 and C18 series long chain fatty acids, due to which microbial lipids can be subjected to transesterification process. High growth rate, short generation time and high lipid content of oleaginous microorganism, under specific conditions, open new prospects for scaling up the cultivation. Although microbial lipid content is high in such microorganism, but process optimization and isolation of organism that can grow on cheap sources of carbon, would add advantage to the production system. Oil from oleaginous fungi has given a new turn to the fuel generation and to the food industries, as their lipid is rich in TAG and the specific PUFA. With the increase in population, demand for food is also soaring, in such scenario food based fuel production will be highly expensive and unwise option, a promising alternative is to look at microbial oil technology as it doesn’t compete with the farmland for crop production. The present chapter focuses on the growth, mechanism and regulation of lipid accumulation in oleaginous filamentous fungi.

Implementation Issues of Adaptive Array Processing for Space borne GPS Receiver

Research and development continues to extend the capabilities and to increase the robustness of global positioning systems (GPS) receivers. Adaptive array antenna have been widely used for GPS receiver for antenna beam-forming & nulling due to its sensitivity to signal multipath and intentional & non-intentional noise sources. It is obvious that the optimum array processing is the best suitable mitigation technique. This RF beam-forming employed in the GPS receiver leads the recent research methodology to mixed mode signal processing. A real time field programmable gate array (FPGA) implementation of MVDR beam-forming were presented here.

Switched Beam Array Antenna for Sectorized Optimum Power Distribution into Discrete Localities of Rural Area

The technology of Switched Beam Array Antenna for mobile communications has received enormous interest worldwide in recent decade. This type of smart antenna (another type is Adaptive Array Antenna) forms a pattern that adapts to the current radio conditions improving the communication link. The principal reason for applying Switched Beam Array Antenna is the possibility for a large increase in capacity and to introduce new services. The purpose of this paper is to give a performance analysis of Switch Beam Smart Antenna (SBSA) using micro strip patch elements with simulation results obtained by using CST Microwave StudioTM, in KCSTC of IIT Kharagpur.

Designing a Frequency Modulated Community Radio Base Station for Rural Community

Issues related to setting up a Frequency Modulated Community Radio Station is discussed.

Software Radio for Rural Telecommunication: Design Issues and Augmentation of Adaptive Equalizer for Spectrum Management and Channel Equalization

Adaptive Equalizer to equalize the unknown time varying channel for Software Defined Radio has been discussed with the help of LMS algorithm. Simulated Result obtained using MATLABTM.

Basic Principle of Beam forming using Array Antenna

Basic principle of Beam forming in Adaptive Array Antenna with analogy with the FIR filter structure antenna and adaptive controlling of radiation pattern through weighting vector is presented.