microHAM SMORF, Руководство пользователя

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11 – SENSOR 1 MENU
SENSOR 1 MENU is a sub menu of the MAIN MENU and serves for all sensor related settings. Actually there
are two sub menus, SENSOR 1 MENU and SENSOR 2 MENU but since both have same sub-menus and
settings, and only difference is that SENSOR 1 menu is associated to the SENSOR 1 and SENSOR 2 MENU is
associated to the SENSOR 2, further description of the SENSOR 1 MENU can be directly applied to the
SENSOR 2 MENU and it won't be described separately.
SENSOR MENU has several sub menus which logically divides sensor settings into several groups.
SENSOR 1 MENU – SENSOR DETAILS
SENSOR DETAILS menu item is informative only. Provides these information:
MODEL: Sensor model
SN: Serial Number of the Sensor
CALIBRATION DATE: Date of the Sensor calibration
CURRENT TEMPERATURE: Internal Temperature of the Sensor
SENSOR 1 MENU – SENSOR CABLES TABLE
SENSOR CABLES menu provides a table where attenuation and phase difference of the cables connecting the
Sensor to the SMΩRF is defined. To understand why this table is important to overall accuracy of the system, it
is necessary to explain how the calibration is made.
The SMΩRF and the Sensor are two separate devices, each is individually calibrated for the amplitude and
phase. SMΩRF is calibrated to the plane of its IN connectors. Sensor is also individually calibrated to the plane
of its SMA connectors and to the plane of the LOAD connector.
If it would be possible to connect Sensor's connectors directly to the SMΩRF's connectors, table wouldn't be
necessary, because only mismatch should be in connectors, and it is negligible at frequencies below 500MHz
(<0.01dB/0.025°) when properly tightened. However, the point of remote sensor is to avoid routing bulky antenna
cable to operating desk, therefore the Sensor and the SMΩRF needs to be connected together by coaxial cables
as sensor provides samples of transmitting signal at its operating frequency. Such cables are far from ideal,
lossless connection, and SMΩRF needs to know how much.
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