In standard analog NTSC (North American) TV, the aural carrier is placed 4.5 MHz above the
vestigial visual carrier ... which I think corresponds to 0.75 MHz from the top edge of the RF
channel but I'm not sure now.
The aural carrier is plain old FM modulated, exactly like the familiar FM radio at 88 - 108 MHz,
except that its peak deviation is 25 KHz instead of 75 KHz ... or about 9.5 dB less audio out of
an identical detector.
Adaptive delta modulation is a analog-to-digital and digital-to-analog conversion technique which is primarily used for voice transmission data and can be used for multiple purposes.
Adaptive delta modulation is a analog-to-digital and digital-to-analog conversion technique which is primarily used for voice transmission data and can be used for multiple purposes.
Adaptive delta modulation is a analog-to-digital and digital-to-analog conversion technique which is primarily used for voice transmission data and can be used for multiple purposes.
Analog
Analog modulationIn analog modulation, the modulation is applied continuously in response to the analog information signal.Common analog modulation techniques are:Amplitude modulation (AM) (here the amplitude of the modulated signal is varied) Double-sideband modulation (DSB) Double-sideband modulation with unsuppressed carrier (DSB-WC) (used on the AM radio broadcasting band)Double-sideband suppressed-carrier transmission (DSB-SC)Double-sideband reduced carrier transmission (DSB-RC)Single-sideband modulation (SSB, or SSB-AM), SSB with carrier (SSB-WC)SSB suppressed carrier modulation (SSB-SC)Vestigial sideband modulation (VSB, or VSB-AM)Quadrature amplitude modulation (QAM)Angle modulation Frequency modulation (FM) (here the frequency of the modulated signal is varied)Phase modulation (PM) (here the phase shift of the modulated signal is varied)
Actually phase modulation was used for the color signal in all analog TV systems.Phase modulation, with some signal preprocessing, was used to indirectly get frequency modulation in many FM transmitters.Certain modems use phase amplitude modulation.etc.
Actually phase modulation was used for the color signal in all analog TV systems.Phase modulation, with some signal preprocessing, was used to indirectly get frequency modulation in many FM transmitters.Certain modems use phase amplitude modulation.etc.
When digital values are converted to create an analog sound, the term used is Digital-to-Analog converter.
Tone modulation through of modulating a carrier frequency using the charactoristics of a sound, its the method used for telephone
Amplitude Modulation (AM) is used for the picture portion of a television transmission while Frequency Modulation (FM) is used for the audio portion.
Well analog is usually used to carry sound so amplifying the analog signal would make it louder.
Pulse position modulation can be analog or digital, it depends on the signal and/or the modulator used to obtain the modulation. If an analog signal is applied at the input of the modulator, the position of the pulse can assume an infinity of different timing states (the signal vary continuously) and hence an analog modulation is realised in PPM. On the contrary if the signal is digitized previously in a series of discrete states, the pulse at the output will have discrete timing interval (not continuosly). Then a digital modulation is obtained. If the signal is analog, but the modulator is digital, we will have again a number of finite state in output timing, and the PPM will be digital. To be noted that, if the number of steps in the digital modulator, is higher then the dinamic range required, the performance of the digital and analog PPM will be exactly the same. Cecking the front of the pulse of PPM with a digital oscilloscope capable of jitter measurament, we will see immediately if the position of the pulses will be continuosly variable or a number of discrete steps will be presented. We can then consider analog and digital PPM physically different.