How is a wave modulated

The identifying characteristics by which you recognize a radio station reflect its two important transmitting features. The frequency, such as The power rating "operating with 50, watts of power" describes the power available to transmit its signal.

The higher the power of the station, the greater the distance at which its signal can be picked up. Bloomfield, Louis A. See also Wave motion. Books Bloomfield, Louis A. Davidovits, Peter. Antenna —An electrical conductor used to send out or receive radio waves.

Carrier wave —A radio wave with an assigned characteristic frequency for a given station to which is added a sound-generated electrical wave that carries a message.

Electromagnetic spectrum —The range of electro-magnetic radiation that includes radio waves, x rays, visible light, ultraviolet light, infrared radiation, gamma rays, and other forms of radiation. Frequency —The number of vibrations, cycles, or waves that pass a certain point per second. Voice is sampled at some rate and then compressed and turned into a bit stream — a stream of zeros and ones — and this in turn is created into a particular kind of wave which is then superimposed on the carrier.

The big question is, why have carrier waves in modulation at all? Why not simply use the input signal directly? So why not use it directly? Why are carriers and modulation needed at all? Interestingly, the input signals could be carried without a carrier wave by very low frequency electromagnetic waves. The problem, however, is that this will need quite a bit of amplification in order to transmit those very low frequencies.

The input signals themselves do not have much power and need a fairly large antenna in order to transmit the information. In order to keep communication cheap and convenient and require less power to carry as much information as possible, carrier systems with modulated carriers are used.

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We use trusted third-party analytics providers to help us improve your experience on this website. Radio Academy. Login Register Search. Topic Progress:. Course lessons. Introduction to Radio Communications Principles. What is Communication? Digital modulation, categorized as either Frequency Shift Key, Amplitude Shift Key, or Phase Shift Key, functions similarly to analog, however where analog modulation is typically used for AM, FM, and short-wave broadcasting, digital modulation involves transmission of binary signals 0 and 1.

Vibration analysis is a process for measuring and analyzing the levels and patterns of vibration signals or frequencies of machinery in order to detect abnormal vibration events and evaluate the overall health of machines and their components.

Vibration analysis is especially useful with rotating machinery, in which exist fault mechanisms that may cause amplitude and frequency modulation abnormalities. The demodulation process can directly detect these modulation frequencies and is used to recover the information content from the modulated carrier wave.

In many telecommunications networks, it is necessary to implement modulation in order for information-bearing signals to be represented by a waveform that can effectively pass through a transmission medium. This modulated signal is then reverted to the original information-bearing signal via demodulation. Disruption of this transmission may occur if there are abnormalities in the modulated signals.

Detecting signal anomalies or abnormal vibration patterns within enormous volumes of data signals is not possible using traditional solutions. Using OmniSci , telco analysts can easily detect and visualize network signal anomalies from billions of rows of records, with point-and-click SQL queries returned in milliseconds.