Introduction Essay Example | Topics and Well Written Essays - 1000 words - 2

Introduction - Essay patternWith this the signal is converted into a form which is compatible with the scheme. For analog form, A/D converter is use for the transmission of the signal, and for digital form, such a block is not require if data already exists in the digital form (Bagad and Dhotre, 2009, p.4-26).PCM PCM or flash-code modulation is a method based on digital encode and are effectively used in optical fibre communications. The baseband video signal in the system is quantified and sampled. There is a series of bits that encodes the sample. The light is put on and off using binary signals. The bandwidth is required to be enhanced over the baseband method for its use. This is a good choice for optical communications, particularly when optical maser diode has to be utilized owing to presence of inherent nonlinearity in the source of the optics (Bandyopadhyay, 2014, p.314).PPM PPM or pulse position modulation is used for optical communications where the code scheme invo lves a bit period divided into two time slots. Data throne either be 1 or 0. If it is 1, the pulse gets transfer in the first bit time slot. If the data is 0, then the pulse gets generated in the second slot of the bit time. Expansion of PPM is to a fault possible and proves to be efficient for optical communications (Alexander, 1997, p.228).Digital PPM PPM can also be used digital transmission of information based on optical communications. It is also referred to as differential pulse position modulation. It is a variation of the PPM coding, which can transmit data disregardless of the presence of time. If delays occur in the transmission, they take reference from falling edge of the pulse that was earlier transmissible (Lazaridis, 2011).Multiple PPM and Dicode PPM Dicode PPM and Multiple PPM are considered as the most efficient bandwidths for optical communications. The best forms of sensitivities are offered by these PPM without causing the large bandwidth of the system to increase.