If you have an RF (Radio Frequency) signal of 1MHz and you modulate it with a signal of 1kHz you end up with three frequencies 1MHz - 1kHz 1MHz 1MHz + 1kHz The carrier is 1MHz. The lower side band is 1MHz - 1kHz or 999kHz while the upper side band is 1MHz + 1kHz or 1.001MHz kHz is thousand cycles per second MHz is million cycles per second
100ms=.1 1Mhz=1000000 .100x1000000=100K timer count
MHz stands for Mega Hertz. Hertz or Hz is unit for frequency and is represented by inverse of time unit i.e. second(-1) i.e. 1/second or per second. Frequency = 1/ time period in seconds 1MHz is 10^6 or 1000000 Hz.
A superheterodyne receiver is a Radio Frequency receiver method that multiplies the received signal frequency with a local oscillator frequency to get frequencies that are the sum and difference of the 2 frequencies. For example, if the received signal is 5MHz and the local oscillator frequency is 4MHz, they are multiplied together. 1MHz and 9MHz frequencies would be gotten. Usually the 1MHz is the Intermediate Frequency (IF). It will be admitted (through a band pass filter) later passed through the required electronic circuits for proper processing. There is also the method of the Variable Tuned Filter.
Like many early microprocessors it has a 1mhz internal clock for its' operation. 12mhz is divided internally by 12 to derive this frequency.
mega = 1,000,000 1MHz = 1,000,000 Hz.
It depends on the signal you are trying to receive. For instance, the AM frequency band lies around 500KHz to 1700kHz. Lets say you have a tuned amplifier such that the resonant frequency was set roughly in the middle of that band at 1000kHz (1MHz). AM radio stations typically space out their broadcasts 9-10kHz. So if Q=f_resonant/f_bandwidth the Q of a tuned amplifier with a bandwidth of 10kHz (which would be decent, maybe a little spill over), would be: Q=1Mhz/10kHz Q=100 The higher the Q, the greater the selectivity. Too high be a bad thing too.
1Mhz (full wave) or 500kHz (half wave) but you didn't describe any type of oscillation so therefore it has no frequency except a vibration. What does Vibration mean? A sound vibration, does that mean noise energy? A material shake, a high noise energy noise pitch from collision or hum?
1Mhz is 1,000,000 (1 million) cycles per second. Mega means million.
a more accurate query would be: Which is faster?quick answer:Gigahertz, meaning One Billion cycles per second.informative answer:hertz, (abbrevieated Hz) refers to a frequency, or rate of speed, of a recurring event. such as the rate at which a video screen flashes images, or the rate at which the special lights on emergency vehicles flash to activate automatic traffic signal 4-way stops. in technology, we use prefixes like mega- or giga- to describe specific amounts or frequencies of somethings, specifically capacity and cyclic frequency. your hard drive may have 100 gigabytes (capacity) of available space. you may have a 2 gigahertz (frequency) microprocessor. so using the International System of Units (look it up, I had to!) we find that mega- multiplies the singular by one million, and giga- multiplies by one billion.so a frequency of 1 GHz means 1 billion cycles per second, 1MHz means a million per second, and 1 Hz means only 1 cycle per second.this means 1GHz is a thousand times as frequent as 1MHz! -Very fast.:)
Wavelength= the distance between successive identical parts of the wave(in meters) Ex. from crest to identical position in next crest. Wavelength is speed of transmission through the medium (usually speed of light) divided by frequency. For example, at the speed of light (3x108 meters per second), a 100MHz radio wave will have a wavelength of 3 meters, while a 1MHz radio wave will have a wavelength of 300 meters.
It is usually a set of sine waves of a specified frequency, for example 10, that start up and stop after the 10 are done. This is one burst, you can have repeating bursts. For example, bursts at a 10% duty cycle could be a burst of 20 cycles of 1MHz, which would take 20µs, then zero volts for 180µs, then another burst, etc. The rep rate of the bursts would be 5kHz in this example
for efficient radiation and reception the transmitting receiving antenna would have to have heights comparable to a quarter-wavelength of the frequency used .This is 75mtr for 1mhz but at 15khz it has increased to 5000mtr .A VERTICAL ANTENNA OF THIS SIZE is unthinkable Second all sound is concentrated within the range from20 Hz to20 kHz, so that all signals from the different sources would be hopelessly and inseparably mixed up .Therefore modulation be needed.
1,000,000 c/s = 1,000 Kilocycles = 1 Megacycles So the answer is 1Mhz, One megahertz. (cycles per second are called Hertz after the bloke who looked into them)
FDM and OFDM both have the same overlap!. In FDM the overlap is in the time domain. In OFDM the overlap is in the frequency domain. First (you may already know this) the relationship between the rectangular pulse and the sin(x)/x (sinc) function: A rectangular pulse in the time domain transforms to and from the sinc function in the frequency domain. A sinc function in the time domain transforms to and from a rectangular "brickwall" function in the frequency domain. In other words these two functions transform to each other by either FFT or IFFT. In both FDM and OFDM we are taking multiple carrier frequencies, modulating them, then combining them for transmission. For simplicity lets assume each carrier is on/off modulated. In idealized FDM, we modulate each carrier then send each though a brickwall filter before combining to the antenna. Say the carriers are separated by 500KHz, (say at 1GHz + 500KHz, 1GHz + 1MHz ...) Each carrier's 500KHz brickwall filter in the frequency domain cause a time domain spreading of its on/off pulses into time domain sinc function with zero crossings every 1us. Now, if we make the baud rate 1Mbps, each bit's ideal sampling point (center if eye) occurs at the zero crossing point of all of the potentially interfering sinc functions from previously received bits. In other words there is lots of ISI, but none at the critical moment when the bits are sampled. This is called "signalling at the Nyquist rate" and is related to but not the same as Nyquist sampling which you hear a lot about. (see en.wikipedia.org/wiki/Nyquist_ISI_criterion, apparently I am not allowed to include link because I am new to physicsforums). Of course brick wall filters are hard to make, so we use things like raised cosine filters that create the same beneficial sinc zero crossings. OFDM is analogous to FDM but with time and frequency domain reversed. We on/off modulate our carriers, but they are combined as unfiltered rectangular pulses and sent straight to the antenna (simplification of course). These time domain rectangular pulses become spread in the *frequency* domain as sinc functions. If we on/off modulate each carrier at 1Mbps (1us symbol time), and simultaneously maintain 1MHz carrier spacing ("orthogonal"), then the zero crossings of the sinc functions occur every 1MHz. Their positions are such that at each carrier frequency, all other carrier's smearing sinc functions have zero crossings. Thus each carrier frequency is free from interference. Again there is plenty of interference between these signals, but none at the critical frequencies where the carriers are located. Note the factor of 2 difference between the OFDM bandwidth and the FDM bandwith in my example. This is due to the convention of including negative frequency in the bandwidth in the OFDM case. Naturally, there is much more to it than this, but this is the basics. Hopefully you can figure out from this where the 50% comes from (look at the superimposed sinc functions).
One way to demodulate an amplitude modulated signal from its carrier is to build a peak-follower. This could be a simple RC filter with a diode at the input. The voltage across the capacitor would charge to the peak value of the carrier (envelope), and then discharge through the resistor. The time constant would be selected so that the capacitor would have no "trouble" following the envelope. Since the typical ratio of signal to carrier frequency is quite high, i.e. 20kHz signal vs 1MHz carrier, the time constant can be quite short.
This is the freq at which the vertical amplifier is 70% of the low frequency response to a sinusoidal input. It's also called the roll off (or cut off) frequency. The vertical amplifier is what sits behind each of the channels on a scope, and allows you to "zoom in" on a signal in the vertical direction (amplitude). A 100MHz scope is capable of displaying a 100MHz sinusoidal waveform but just that it's going to show it at 70% of the amplitude that it displays at ,say, 1MHz. This assumes the input signal does not roll off in amplitude. The scope is able to display higher frequencies, it's just that it cannot react to higher and higher freq. The roll off is defined by a -6dB/octave "curve", which when plotted on a log freq scale is a negative slope above the cut off freq.
Modulation is the process of varying a particular characteristic(amplitude,phase,frequency) of a high frequency carrier signal according to the message signal.The need of modulation is as follows:-1.Reduces the height of antenna :-The minimum height of antenna required for transmission or reception of RF signals is one forth the wavelenth i.e lower the frequency,higher the wavelenght ,greater the length of the antenna .eg.for wave of 15Khz,antenna height is 5km,which is impractical but for 1Mhz wave,height is 75 m.2.Increases the range of communication:-At low frequencies,radiation is poor and signal gets attenuated.Modulation effectively increases the frequency of the message signal and thus signal can be transmitted over longer distance without attenuation.3.Avoids mixing of signals and allows multiplexing of signals:-When many signals are transmitted simultaneously,they may get mixed and it becomes difficult to separate them at the receiver end.This can be avoided by modulating different signals with different carriers i.e. each signal is allocated a separate bandwidth.At the receiver end,required signal can be intercepted by the tuning the receiver to desired frenquency bandwidth.This allows multiplexing(i.e. transmission of more than one signal simultaneously over the same channel.)eg.channels on television4.Improves the quality of reception:-Modulation techniques like frequency modulation reduce the effect of noise and improve the quality of reception.
20PU = 20mhz clock 10PU = 10mhz clock note that these are the maximum clock speeds. voltage and settings will apply also. I believe most AVR's default to 1mhz until you have set the specified fuse setting.
CPU speed is often measured in Hertz [Hz] which is simply cycles per second. One thousand Hertz = 1kHz (kilohertz) One million Hertz = 1MHz (Megahertz One billion Hertz = 1GHz (Gigahertz) One thousand billion Hertz = 1 THz (Terahertz)
i think because of the three bit (LT_ADDR), the logical transport address which is used by the master to identify the destination -the active slaves- and as u know 3 bit combination generates 8 codes. the second reason -not sure- because of the limitation of the physical channel (1MHz) which is time multiplexed in the piconet.