Describe the source of the EMG signal and what the shape of the
signal represents in the patient.
How is the source of an EEG signal located on an
individual?
How does a cochlear implant allow a patient to hear different
frequencies?
What does an ECG measure?
Can cardiac ablation be used to treat under-active cardiac
tissue? Explain.
What are the characteristics of the EMG? Bandwidth (frequency
content)? Magnitude (amplitude)? How will determining
the bandwidth guide your filter design? How will
determining the amplitude guide your amplifier design? Using
these criteria and support information, roughly design an amplifier
(provide a circuit schematic) to accomplish these tasks. What will
be the gain of your amplifier, what type of filter do you need,
what are the cut off frequencies?
What are the characteristics of the EMG? Bandwidth (frequency
content)? Magnitude (amplitude)? How
will determining the bandwidth guide your filter design? How
will determining the amplitude guide your amplifier design? Using
these criteria and support information, roughly design an amplifier
(provide a circuit schematic) to accomplish these tasks. What will
be the gain of your amplifier, what type of filter do you need,
what are the cut off frequencies.....
What is the amplitude of a typical ECG signal is as measured
directly from skin surface electrodes? How will this answer guide
your amplifier design? What features can you incorporate in your
measurement device to reduce noise (especially at 60 Hz)?
1. Discuss what will happen to the modulation process of an
amplitude modulation (AM) signal if the carrier signal level
remains constant and the sideband signal level increases and
justify your answer
2. A normal modulation usually has a modulation index ranges
from 0 to 1 but in some rare cases, the modulation index can be
greater than 1. Discuss what will happen to the output of the
receiver if this situation happens.
Faraday's Law: What would you observe about the amplitude of an
induced signal as the frequency varied? Describe whether the
behavior is consistenent with Eq. 3 (Vo= w(Nd)A(Bo)cos(theta)). In
particular what should your graph of amplitudes against frequencies
look like according to Eq 3? In comparisons with the predictions of
Eq 3, why would it be important to adjust the function generator to
keep the amplitude of the B field the same at each frequency?
A carrier signal of (500 kHz) is amplitude modulated to a depth
of 75% by a single tone modulating signal of 18 KHz. The carrier
amplitude is 800 Volts , and the antenna equivalent impedance is 70
Ohms. Calculate:
1- modulating wave voltage (Am) [volt]
2- The carrier power (Pc) [Watt]
3- The average output Power (Pt) [watt]
4- The percentage transmission efficiency [%]
5- The lower side band power (PLSB)
Electromyography (EMG)
(a) Consider the technique
of electromyography (EMG) to examine muscle function about joints
during movement. Explain where the captured, high frequency raw
signal originates, and describe the physiological basis with
reference to the relevant parts of the neuromuscular
system. [8
marks]
(b) When processing EMG signals, the
following terms are frequently encountered in the literature:
(i) Band Pass filtering
(ii) Full wave rectification
(iii) Normalisation to maximum
voluntary contraction (MVC)
(iv) Median frequency
Please explain what each of these terms...
A carrier signal with unit amplitude and frequency fc1 = 50 kHz
is modulated with a message signal
?1(?)=2cos(2??1?), where f1 = 15 kHz, to produce a DSB-SC signal.
This DSB signal must be up-converted to a center frequency fc = 100
kHz.
a. Determine the image frequency of the DSB signal. [2]
b. An Upper-SSB signal with unit amplitude carrier at the image
frequency calculated above also exists in the spectrum. The SSB
signal is tone modulated with ?2(?)=4cos(2??2?),...