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Absorptive Device |
The device that maintains the specified VSWR and absorbs all power in high loss state. |
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Accuracy/Linearity |
In VVAs, the variation of the mean attenuation from the best straight line of attenuation vs. control signal transfer function. |
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Analog Attenuator |
A unit where continuously variable attenuation level is controlled either by an applied current (driver-less unit) or applied voltage (unit with driver). |
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Attenuation Accuracy |
The maximum deviation of the mean attenuation from the nominal value of the set attenuation in dB. |
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Attenuation Flatness |
The attenuation variation from the mean attenuation over the specified frequency range for a given attenuation value in dB. |
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Bias |
The control voltage and/or current signals supplied to the unit which provide proper unit operation for devices without integral drivers. |
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Commutation |
Applies to multi-throw switches when, with all other ports set to isolation, one port is switched from insertion loss to isolation and simultaneously another is switched from isolation to insertion loss. |
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Digital Attenuator |
Attenuator with integral driver where control inputs are logic bits and there is no continuous adjustment of attenuation. Attenuation levels are discrete (individual), defined by the number of bits the devices use and the maximum unit attenuation and logic levels applied. |
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Driver |
The circuit used to convert logic command signals to the bias conditions needed to execute control of active devices. |
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Fall Time |
See Switching Speed |
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Frequency Range |
Frequency range over which a unit must meet
specified performance. |
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Insertion Loss |
The difference, measured in dB, between input power and output power levels when a unit is in low-loss condition. |
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Isolation |
The difference, measured in dB, between input power levels and output power levels when a unit is in high-loss condition.
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Mean Attenuation |
The average of maximum and minimum values of the attenuation over the specified frequency range for a given attenuation value in dB. |
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Modulation |
When, with all other ports set to isolation, one port is repeatedly switched ON and OFF. |
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Monotonicity |
The increase of attenuation level as the control input level increases. At no point does an increase in control input state cause a decrease in attenuation at any frequency or attenuation level. |
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Operating Power |
The maximum power over which the unit must meet specified performance. |
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PIN Attenuator |
A two-terminal device capable of providing a prescribed RF attenuation based on the level of control applied. |
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PIN Switch |
An N terminal device which routes input signals to any one of the outputs or isolates that output - achieved by applying external bias and control inputs. |
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Recovery Time |
(Limiters) The time designation for the transition from high loss state to low loss state following the secession of high power pulse. This period is defined as the time period from the end of high power pulse to the point where the insertion loss value has returned to within 3 dB of the quiescent loss state. |
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Reflective Device |
The device that reflects the incident power back to the source when a port is in high loss state. |
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Rise Time |
See Switching Speed |
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Survival Power |
The maximum level to which the unit can be subjected without incurring possible permanent performance degradation. |
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Switching Speed |
T Off: The time between the 50%-point of the input control pulse and the 10%-point of the detected RF power, when the unit is switched from insertion loss ON to isolation OFF.
T On: The time between the 50%-point of input control pulse and the 90%-point of the measured RF power, when the unit is switched from isolation OFF to insertion loss ON.
Rise Time: The time between the 10% and 90% points of the measured RF power, when the unit is switched from isolation OFF to insertion loss ON.
Fall Time: The time between the 90% and 10% points of the detected RF power, when the unit is switched from ON to OFF.
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T Off |
See Switching Speed |
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T On |
See Switching Speed |
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Temp. Range |
The temperature range over which a unit complies with specified performance. |
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VSWR |
The voltage standing wave ratio of a unit when the in-band signal is incident.
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VVA Linearity |
In VVAs, the variation of the attenuation from the best straight line of attenuation vs. control signal. |
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