Vast majority of consumer media content is stored digitally on computers.
Consumers would like to see their media content on a TV.
Background
Technology Pros ConsWire Cheap Not always feasible
Wi-Fi based • Exiting infrastructure• ‘Smart’ TVs
• QoS• Cost• Setup
Custom Transmitter & Receiver
• QoS • Cost• Setup
Common existing methods
Every TV has a wireless tuner to receive broadcast TV
Not all channels occupied by stations
FCC regulation allows for licence-free low power broadcast within the UHF band
Background
Investigate feasibility of building a low-power portable transmitter, operating within the UHF band.
Living room equivalent of FM transmitters for listening to music in the car
Purpose
Minimize hardware costs Scalability: point to multipoint Utilize existing infrastructure Ease of setup
Advantage
Criteria Digital (ATSC) Analog (NTSC + BTSC)
High Definition Yes NoQoS Better AverageExisting infrastructure Average BetterImplementation complexity
High Medium
Cost High Low
Broadcast method
Support commonly used digital media storage formats (H.264, MPEG 2, MPEG 4, etc…).
USB for power and PC interfacing. Portable form-factor ready.
Design Objectives
Reference: Dell Unveiled USB Digital TV Tuner [online], Available: http://www.mr-gizmo.com/tag/digital-tv-tuner/
Input: NTSC video and BTSC audio. Output: UHF modulated signal. Freescale MC44BS373CA.
◦ Capable of modulating on channels 14-69 (471.25 MHz – 801.25 MHz).
RF Modulator
Input: 2-channel analog audio. Output: Stereo encoded audio. Freescale MC44C402.
BTSC Stereo Encoder
Two stage amplifier boosts the power level of the RF modulated signal.
Total simulated gain of 44 dB◦ High IP3 points and unconditionally stable.
Amplifiers
Mini-Circuits RF Amplifier
Testing and Results
Spectrum Analyzer Output Parameters
Power (dBm)
Actual -11Simulated 10Maximum (FCC)
17
Use digital modulation techniques (ATSC). Improve output power. Minimize size. $38/unit.
Commercialization Proposal
Reference: Dell Unveiled USB Digital TV Tuner [online], Available: http://www.mr-gizmo.com/tag/digital-tv-tuner/