PPT-Spread Spectrum Techniques

Frequency Hopping Direct Sequence 1 Shannons Theorem and Nyquists Theorem channel capacity bps channel bandwidth Hz SNR is the signaltoNoise ratio Unitless. spreadorg Spread provides a range of reliability ordering and stability guarantees for message delivery Spread supports a rich fault model that includes process crashes and recoveries and network partitions and merges under the extended virtual sync 381a and b brPage 4br mt Fig 7381 b Direct sequence spread spectrum receiver Fig7381 b Binary Adder Balanced Modulator Pseudo noise code enerator Transmitted signal st ct Carrier Frequency f Fig 7381 a Direct sequence spread spectrum transmitter mt As the spectrum is limited so the sharing is required to increase the capacity of cell or over a geographical area by allowing the available bandwidth to be used at the same time by di64256erent users And this must be done in a way such that the qua 4. Modulation. Modulation. Radio signals can be used to carry information. Audio, data, video. Information is used to modify (modulate) a single frequency known as carrier. Modified(modulated) signal is transmitted to receiver . RECORDINGMICROPHONE TECHNIQUES 3 Microphone Techniques.............4..................................................................................5Microphone Techniques ........................... 1. Dr. Nikhat Siddiqi. THE NATURE OF LIGHT. Light is composed of electric and magnetic fields, which . are mutually . perpendicular and which . radiate out from a source. in all directions (Figure . ). . Resource Allocation Techniques for Cellular Networks in TV White Space Spectrum Farzad Hessar, Sumit Roy University of Washington April 2014 Outline Introduction Primary/Secondary Network Architecture Conveniencia y ahorros para tus clientes. . Varios servicios por un solo bajo precio.. Un pedido, una factura.. Cero contratos.. Clientes de alto valor.. Un paquete de servicio = Hasta . 4 puntos por clientes. Modulation is the process of encoding the baseband or source information (voice, video, text) in a manner suitable for transmission.. It generally involves translating a baseband signal (or source) to a band pass signal, centered at a high carrier frequency.. Transmission security can be accomplished by either of two ways:. 1-Using . adaptive phased array null steering antenna. The null of the radiation pattern of a phased array antenna is forced to be directed toward an intentional jammer to get rid of its effect. This is the case when we need . 1. Introduction. By. Ms.A.Thamizhiniyal. , M.C.A., M.Phil.,. Assistant Professor,. Bon Secours College for Women, . Thanjavur. Definition. Mobile communications. refers to a form of . communications. spread a signal over a wide bandwidth (larger than BW in traditional communication systems). - These techniques are used for a variety of reasons, including the establishment of secure communications, increasing resistance to natural interference, noise and jamming. CONTENTS. INTRODUCTION. SPREAD SPECTRUM COMMUNICATION? . HOW IT WORKS. SPREAD SPECTRUM TECHNIQUES. APPLICATIONS. ITRODUCTION TO SPREAD SPECTRUM COMMUNICATION. Spread-spectrum radio communications is a . Paul Kolodzy, PhD. 6 April 2016. 1. CSMAC is investigating the challenges associated with spectral measurements for spectrum sharing. Moving from . non-directional transmissions . at lower frequencies to more .