SECTION 1 : BASIC PRINCIPLES OF COMMUNICATIONS ENGINEERINGJ. AMPOLOQUIO Electronic Transmission, reception, and processing of information between two Communication or more locations using electronic circuits Allocation Entry in the table of frequency allocations of a given frequency band Allotment Entry of designated frequency channel in the agreed plan for the use of two or more nations Assignment Authorization given by a nation for a radio station to use frequency channel under specified conditions Hans Christian Discovered relation between electricity and magnetism in 1820 Oersted Andre Marie Ampere Observed the phenomenon of electromagnetic induction; hypothesized the existence of magnetic field around a current carrying conductor (1821) Michael Faraday Discovered electromagnetic induction; reverse of Oersted’s discovery (1822) Joseph Henry Demonstrated telecommand, wire telegraphy was born Samuel Morse Exploited Henry’s invention commercially James Clerk Maxwell Hypothesized the existence of EM waves (1866) Heinrich Hertz Radio waves (1886) Guglielmo Marconi Developed the first wireless telegraph; used spark gap transmitter (1896) Major Edwin First successful FM radio system (1900) Armstrong Reginald Aubrey Invented AM (1936) Fessenden Wired Medium The signal is confined within the proximity of the channel; bounded or guided Wireless Medium Signal is not subjected to limits; unbounded or unguided White Noise Noise that has equal amount of energy per octave Brown Noise Similar to pink noise but with a power density decrease of 6dB per octave Blue Noise Doubles the amount of energy as you go up 1 octave Purple Noise/ Violet Differentiated white noise; increases 6dB per octave Noise Orange Noise Quasi stationary noise with a finite power spectrum with a finite number of small bands of zero energy dispersed throughout a continuous spectrum Black Noise Noise that has frequency spectrum of zero power level over all frequencies except for a few narrowband or spikes such that outside f1<fo< f2.707 times the maximum value of magnitude f2 – f1. the magnitude spectra fall no lower than 0.A3E H3E J3E R3E C3F Amplitude Shift Keying CP FSK Standard Oscilloscope Frequency Wavelength Period Spectrum Analyzer Doppler Effect Absolute Bandwidth -3dB Bandwidth or Half Power Bandwidth Null-to-Null Bandwidth Bounded Spectrum Bandwidth Power Bandwidth FCC Bandwidth ITU Necessary Bandwidth Region 3 Class of Signal ITU Emission Designation FCC Emission Double sideband full carrier Single sideband full carrier Single sideband suppressed carrier Single sideband reduced carrier Vestigial sideband modulation On off Keying Continuous Phase FSK Used to display the amplitude versus time representation of the input signal Number of times a particular phenomenon occurs in a given period of time Distance between two points of similar cycles of periodic wave Time required for one cycle of a repetitive system Used to display amplitude versus frequency representation of the input signal A perceived change in the frequency of a wave as the distance between source and observer changes f2 – f1. where for frequency inside f1<f< f2. where the spectrum is zero outside the interval along positive frequency axis f2 – f1. where f2 is the first null in the envelope of the magnitude spectrum above fo f2 – f1. power spectrum density must be at least a certain amount below the maximum value of PSD Defines as the frequency band in which 99% of the total power resides Authorized bandwidth parameter assigned by FCC to specify spectrum allowed Width of the frequency band that is just sufficient to ensure transmission Includes Philippines Given by 3 alphanumeric symbol 1st Symbol : type of modulation 2nd Symbol : nature of signal 3rd Symbol : type of information 4th Symbol : detail of signal 5th Symbol : nature of multiplexing 1st Symbol : type of modulation . unique band of frequency on each channel on continuous time basis Time Division Multiplexing.544 Mbps to 45 Mbps (US).Designation Simplex Half Duplex Full Duplex Full/Full Duplex Two-wire 4-wire FDM TDM STDM WDM Narrowband Wideband Broadband Attenuation Distortion Noise Distress Urgency Safety 2nd Symbol : type of transmission 3rd Symbol : supplementary character Only in one direction Both direction but not the same time Two way simultaneous Transmit and receive simultaneously but not necessary between same two locations Those that carry information signal in both directions over the same path Over separable paths Frequency Division Multiplexing.048 Mbps to 34 Mbps (European) 45 Mbps (US). 34 Mbps (European) Due to resistance and length of transmission medium Alteration of information which original proportion is changed Outside source which corrupts the signal Needs immediate assistance Requires immediate attention Meteorological information . each channel is allotted fixed time slot occupying the entire wideband frequency Statistical TDM Wavelength Division Multiplexing. sending information signal that occupy same frequency at the same time Single channel (64Kbps) or some of 64Kbps channels (N x 64Kbps) but less than wideband Multichannel capacity. 2. 1. 0 TLP = 0dBr dB above reference noise dB adjusted dB above reference noise using C-message line weighting dBrnC = dBa +5 (pure test tone) dBrnC = dBa +6 (3KHz white noise) dB psophometrically weighted Picowatts psophometrically weighted Used to measure the power level of program channels and certain types of speech or music P (dBm) = VU -1. buckshot. American term for RLP. or spurious emissions. 1/f2 Transmission unit used in Northern European countries used to express attenuation of current along transmission line using natural logarithm.686 Db Relative level point Transmission level point. overmodulation is illegal Standard AM broadcast band. 107 carrier assignments . frequency or phase perturbation The reverse process where the received signals are transformed back to their original form An analog modulation scheme in which the amplitude of relatively high-frequency carrier signal is varied in accordance with the instantaneous amplitude of an information signal Vam(t) = (Vc + Vmsin ῳmt) sin ῳct Describes the amount of amplitude change present in an AM waveform Created side frequencies (harmonics) further from the carrier known as splatter. AMPOLOQUIO The process of impressing or imparting a low-frequency source information onto a high-frequency bandpass signal with a carrier frequency by the introduction of amplitude.Noise Impulse Noise Burst Noise Neper RLP TLP dBrn dBa dBrnC dBmp pWp Volume Unit SECTION 2 : NOISE ANALYSIS AND DB CALCULATIONS AMPOLOQUIO Any undesirable energy that falls within the passband of unwanted signal Sudden burst of irregularly shaped pulses Popcorn Noise. 1 Neper = 8.4 Modulation Demodulation Amplitude Modulation AM modulated wave Coefficient of Modulation Overmodulation 535KHz to 1605KHz SECTION 3 : AMPLITUDE MODULATION J.