INTRO TO SIGNAL PROCESSING REVISION QUESTIONS Flashcards
What is meant by SP in the context of Clin Phys?
-
What processes do we apply to biological signals to create our desired output?
- amplification
- filtration
- noise reduction
- digitisation -ADC/DAC
- digital signal storage and analysis
What are the components of out measurement system from measuring to output?
Measurand -> Transducer -> Signal Processing -> Display Device -> Output
My Terrifying Snake Dances
Ominously
Can you provide examples for each component?
Measurand
- Biopotential
- Pressure
- Temperature
- Sound
- Light
- Volume
Transducer (Later flashcards)
SP
- Amplification
- Filtration
- Noise reduction
- Digitisation
- Digital signal storage/analysis
Display
Cathode Ray Oscilloscope (CRO)
LED screen
Sphygmomanometer
Chart Recorder
Output
- ECG/EGM
- Oxygen Saturation
- Cardiac Output
- Lung Volumes
- Echo
- Blood Pressure
What is a transducer?
- conversion of energy from one form to another (that is usable)
What transducers are used in clinical measurement?
- Non-invasive electrode (e.g skin electrodes ECG/wires)
- invasive e.g. pacemaker leads
- Strain gauge used in cardiac catheterisation
- Thermistor
- Pieze-electric crystal used in ultrasound
Describe each transducers functions:
- Non-invasive electrode
–> Conducts biopotential through material of the electrode and converts potential difference along the ecg wire/cables
-Strain gauge
–> wire that changes resistance dependent on pressure converting mechanical pressure into an electrical signal
- Piezo-Electric Crystal
–> emits electrical signal when deformed by sound waves
Most appropriate transducer for each?
- ECG –> Non invasive
- SpO2 –> Light Sensor
- Flow loop recording –> strain gauge
- Cardiac catheterisation –> Strain Gauge
define amplification
-
define filtration
-
define noise reduction
-
define digitisation
-
define digital storage
-
Measuring to Output tables
MEMORISE
