Microchip Technology GridTime 3000, Руководство по установке

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GNSS Lower Baseband Signal Upper Baseband Signal
GLONASS L2OF (1246 MHz + k*437.5 kHz, k=
-7, …, 5, 6) L1OF (1602 MHz + k*562.5 kHz, k=
-7, …, 5, 6)
Galileo E5b (1207.140 MHz) E1-B/C (1575.420 MHz)
BeiDou B2I (1207.140 MHz) B1I (1561.098 MHz)
Any number of the supported GNSSs can simultaneously be used for time synchronization. Either their upper signal,
or simultaneously their upper and lower signals can be used for synchronization.
It is best to utilize as many GNSSs and GNSS basebands as possible. This can improve accuracy, make jamming
and spoofing more difficult, and removes vulnerability to a malfunction or deliberate denial of a particular GNSS
system.
When synchronized to one or more GNSS signals, the device’s Clock Management Tool and LCD dashboards will
show ‘GNSS’ as the current time source See
Table 2-2 LCD Tab Information .
6.7.1 Microchip Antenna Kit versus Custom Equipment Installations
This section describes the differences between custom GNSS and antenna equipment and the Microchip antenna kit.
The GNSS receiver inside the device is highly sensitive and supports a wide range of antenna and lead-in cable
combinations. However, the Microchip antenna kits are recommended in preference to other equipment, and support
cannot be guaranteed if equipment issues result from custom equipment choices. The Microchip antenna kits have
been tested with the GridTime 3000 and are proven to give good GNSS performance.
The Microchip antenna kits offer a range of cable lengths and protection levels. They are electrically compatible with
the device’s antenna port and are compatible with all supported GNSS input signals. See the antenna kits section for
detailed specifications of each antenna kit.
If custom equipment is chosen, read the next three sections on custom antenna installation recommendations,
otherwise, skip to the ‘
All installations ’ sections.
6.7.2 Custom Installation - Antenna Port Input Requirements
This section describes the input requirements that must be met by a custom antenna installation.
Custom antenna installations must meet the antenna port input specifications in Antenna Port Input Specifications .
Table 6-12. Antenna Port Input Specifications
Parameter Specification
Signal Type Must support at least one of the following: GNSS L1C/A, L2C, L1OF, L2OF,
E1B/C, E5b, B1I, or B2I
Gain Between 15 dB and 30 dB of gain including gain of antenna and loss of cable
and inline components
Frequency Must support frequency bands used by the desired signal types
Impedance 50 ohms
Coupling DC-center pin provides power to GNSS antenna or inline amplifier
Output voltage to antenna 5 Vdc
Output current to antenna 80 mA maximum
Connector type Female TNC connector
Decal label ANT1
Installation
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2022 Microchip Technology Inc.
and its subsidiaries
Manual
DS00004572A-page 52