Term	Definition
Aircraft Hardware Unit	The Horizon Hardware Unit mounted on the aircraft
Beam	Somewear’s software platform encompassing multiple product line integrations, including Horizon UI
BEC	Battery Eliminator Circuit
BLOS	Beyond Line of Sight
CAB	Spectreworks Common Avionics Board (target flight controller for Kit A)
DANL	Displayed Average Noise Level
Darkstar	The Horizon variant equipped with an Inmarsat satellite modem in place of the standard Iridium modem
DFU	Device Firmware Update
EMI	Electromagnetic Interference
FDMA	Frequency Division Multiple Access
GCS	Ground Control Station
GCS Hardware Unit	The Horizon Hardware Unit installed at the GCS laptop or terminal
Horizon	The product line encompassing the Horizon Hardware Units and their associated Beam/Horizon UI integration
Horizon Hardware Unit	Either of the two identical hardware units comprising the Horizon system
Horizon UI	The Horizon-specific component and control interface within the Beam software platform
I/O	Input/Output
Inmarsat	L-band geosynchronous satellite network (BLOS modem option on Horizon Darkstar units)
Iridium	LEO satellite constellation (default BLOS modem)
LOS	Line of Sight
MAVLink	Micro Air Vehicle Link (UAV communication protocol)
OCP	Overcurrent Protection
OTA	Over-the-air
PER	Packet Error Rate
PLI	Position Location Information
RC	Radio Controller
RF	Radio-frequency
SBD	Short Burst Data (Iridium messaging service)
SERIAL1	Flight controller serial port used for telemetry
TAK	Team Awareness Kit
TDD	Time Division Duplexing
TDMA	Time Division Multiple Access
UART	Universal Asynchronous Receiver-Transmitter
UAS	Unmanned Aircraft System
USB	Universal Serial Bus