logarithmic amplifier

logarithmic amplifier

[′läg·ə‚rith·mik ′am·plə‚fī·ər]
(electronics)
An amplifier whose output signal is a logarithmic function of the input signal.
References in periodicals archive ?
The logarithmic amplifier (LA) is an effective alternative to the AGC circuit; the logarithmic amplifier refers to an amplifier for which "the gain must be linear until a certain level of the input signal is reached, after which the gain must be unity" [23].
What's a logarithmic amplifier and where would I use one?
TRW pursued four process technologies, including a 0.5- and a 0.25-||micro~meter~ MESFET process in a HEMT configuration; a successive detection logarithmic amplifier, built in an HBT HEMT process with a 0.2-||micro~meter~ gate length as shown in Figure 5; and a power FET with a 0.5-||micro~meter~ gate length in the configuration of a Ka-band balanced LNA.
Even though CDMA carriers with equal total power are applied, the experimental results, using a logarithmic amplifier as a detector, have shown nonlinearities as a function of the numbers of carriers and their frequency separation.
"Accurate Power Detection of a CDMA Multicarrier Power Amplifier Using a Logarithmic Amplifier," No.
The receiver employs a logarithmic amplifier in the analog baseband to compress the signal dynamic range before the analog-to-digital converter.
The logarithmic amplifier which was the subject of the prototyping activity is based on the use of an anti-parallel diode pair in the feedback loop of the operational amplifier, as shown in Figure 1.
In essence, the demodulating logarithmic amplifier is an RF-to-DC converter.
This new logarithmic amplifier combines low cost, small size and low power consumption along with high accuracy and stability, high dynamic range and wide operating frequency range for use in today's high performance radar, communications and instrumentation equipment.
Dolan stated that TRW is pursuing five process technologies as the baseline technologies, including a 0.5 [Mu] m process; a 0.25 and 0.5 [Mu] m MESFET process in 0.2 quarter-micron HEMT configuration; a successive detection logarithmic amplifier, built-in HBT, HEMT process with 0.2 [Mu] m gate length, as shown in Figure 7; and a power FET with 0.5 [Mu] m gate length, as shown in Figure 8, in the configuration of a Ka-band balanced LNA.
This logarithmic amplifier technique can be extended to frequencies well above 1 GHz by the use of modern monolithic integrated RF amplifiers.