Functional Description of TIS-09 Wheel Unit Type ASK/FSK 433.92 MHz Tire Pressure Generation _______________________________________________________________ FCC ID: KR5TIS-09 IC: 7812D-TIS09 1 of 3 1. SYSTEM OVERVIEW The tire pressure monitoring system (referred as TG for Tire Guard) consists of the following units:
- Tire guard wheel unit type TIS-09 which includes an integrated pressure, temperature and acceleration sensor and a RF transmitter.
- LF receiver unit which includes a LF receiver (not described in this document) The TG monitors a vehicle's tire pressure whilst driving or stationary. An electronic unit (wheel unit) inside each tire, mounted to the valve stem, periodically measures the actual tire pressure. By means of RF communication, this pressure information is transmitted to the RF receiver. 2. TECHNICAL DESCRIPTION Carrier frequency:
Number of channels:
Type of modulation:
Baud rate:
Rated Output Power:
Antenna:
Voltage supply range:
433.92 MHz 1 Amplitude Shift Keying (ASK), Frequency Shift Keying (FSK) 9600bps
< 10mW Internal 2.1 up to 3.2V 3. TYPICAL USAGE PATTERN 3.1 AVERAGE FACTOR CALCULATION (Standard 47 CFR Part 15C (periodic intentional transmitter)) Maximum transmitting duration in whatever 100ms windows: 10.31ms
Averaging factor = 20xlog(10.31/100)=-19.73dB ToleranceBaudrate 1%:=
+
2bit 12byte
:=
9600bps
:=
:=
98=
Baudrate Framebyte Framebits
:=
tbit Framebits Framebyte 1 Baudrate 1 ToleranceBaudrate
(
)
=
tbit 0.10522ms tFramebits tFramebits
:=
=
tbit Framebits 10.31145ms tFrameFSKbits
:=
tFramebits 1 due to FSK 100%
AveragingFactor_tFrame
:=
20log tFrameFSKbits 100ms Averaging Factor_tFrame = -19.8dB _______________________________________________________________ FCC ID: KR5TIS-09 IC: 7812D-TIS09 2 of 3 1 of 3
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ASK WUP: 320 bits Baudrate= 9600bps/s (+/-1%) ASK: 50% duty cycle Max WUP duration = 16.83ms AveragingFactor_tWUP
:=
20log tWUPFrameASKbit 100ms Averaging Factor_tWUP = -15.5dB Note: The time between inter frames is always higher than the 100ms FCC window.
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"NCC Warning Statement Article 12 Without permission, any company, firm or user shall not alter the frequency, increase the power, or change the characteristics and functions of the original design of the certified lower power frequency electric machinery. Article 14 The application of low power frequency electric machineries shall not affect the navigation safety nor interfere a legal communication, if an interference is found, the service will be suspended until improvement is made and the interference no longer exists."
_______________________________________________________________ FCC ID: KR5TIS-09 IC: 7812D-TIS09 3 of 3