Exam 1 Flashcards
(42 cards)
Mobile Market Share
Worldwide:
Android ~ 70%
iOS ~ 29%
USA:
Android ~38%
iOS ~ 61%
Low-Band spectrum
under 3 GHz
Usage of 99.7%
provides most range
High-Band spectrum
above 24 GHz
yards not miles
larger capacity + ultra fast speeds
Mid-Band spectrum
3-24 GHz
blend of low + high characteristics
GSM
Global System for Mobile Communications
CDMA
Code Division Multiple Access
FCC (Spectrums)
Spectrum is finite
FCC oversees spectrum allocation
raises money for U.S treasury, auctions with bids for frequencies
NFC (Near Field Communication)
Range of few cms
Sends encrypted data
UWB (Ultra Wide Band)
“pulse radio”
Short range, high bandwidth / data rates
30-600 feet, 700+ Mbps
centimeter level accuracy
Time of Flight // Angle of Arrival
Camera
Used to detect motion
Facial recognition
Augmented Reality
Microphone
Sound detection
Fingerprint Sensor
Biometric authentication
Heart Rate Sensor
LED emits light towards the skin,
sensor looks for the light waves
reflected by it. Heartbeat measured by counting the changes in light intensity between the minute pulsations of the blood vessels.
Motion Sensors
Measure acceleration forces and rotational forces along three axes
Environmental Sensors
Measure various environmental parameters of the surrounding area of the device
Position Sensors
Measure physical position of a device.
Accelerometer
Axis-based motion sensing. Senses the changes in
the orientation of smartphones with respect
to x, y, and z-axis
Gives orientation as to the way a device is held
Measures movement(acceleration)
Uses:
○ Switches apps from portrait to landscape
○ Can tell if phone is facing up or down
○ Shows your speed in a driving app
○ Motion & shake detection
○ Track Steps for Fitness apps
Gyroscope
measures angular rotation across 3 axes
Detects how much the phone is titled or rotated
Provides directional orientation details -> Up/down and left/right
Usages:
○ Pokemon go
○ Google Sky Map
precision for 360 photo spheres images
Tilt steering in racing games
Ambient Light Sensor
detects the light around your environment
can adjust screen brightness
Barometer Sensor
measures air pressure
○ detects weather changes
○ Detects distance from sea level or your altitude
○ Increases accuracy in fitness apps, like step tracking
Ambient Temperature Sensor
measures air temperatures of immediate
surrounding
- Not in all phones
Ambient Humidity Sensor
Measure humidity of an environment
Monitors dewpoint
- Not in all phones
Geiger Counter
Measures radiation level in area
- rare
Proximity Sensor
usually located near the top speaker
combines an infrared LED & light detector to know how close the phone is to an object
- Know when your phone is closer to your face to turn off
the screen - The sensor emits a light beam (invisible to the
human eye), which bounces back to the device