A29-A32 Receiver Couplers; A33-A36 Test Port Couplers - Keysight N5227A Service Manual

PNA Series Microwave Network Analyzers Theory of Operation
N5227A Signal Separation Group Operation
Normal Measurement Configuration
The Option 419 analyzer is equipped with a configurable test set and source attenuators. With this
configuration and inclusion of an external amplifier and accessories, you can calibrate the analyzer and test
devices at power levels up to +30 dBm. You can make measurements in the forward, reverse, or both
directions and still achieve these high power levels.
High Dynamic Range Measurement Configuration
With a few jumper changes, you can configure the measurement configuration for higher dynamic range
measurements. By swapping the front panel jumpers for one port, signal flow through the corresponding
coupler is reversed, increasing the test signal sensitivity by 15 dB.
In the forward direction, for example, the signal flow through the test port 2 coupler (A36) is reversed by
arranging the front panel jumpers such that RCVR B IN connects to CPLR THRU and CPLR ARM connects to
SOURCE OUT.
While increasing forward (S ) dynamic range, the reverse (S ) dynamic range is degraded by the same
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amount.
A29–A32 Receiver Couplers
The source incident signals from the A5 and A10 26.5 GHz sources are sent to the A29–A32 receiver
couplers where a portion of each signal is coupled off to provide the R1, R2, R3, and R4 receiver reference
signals for 4-port models or R1 and R2 reference signals for 2-port models.
These reference signals are routed through front-panel jumpers to the A27 and A28 mixer bricks. Refer to
"A27 and A28 Mixer Bricks" on page 5-25 for additional information.
The test signals each go through the through-line arm of a receiver coupler, then through a front panel
jumper to the A33–A36 test port couplers.
A33–A36 Test Port Couplers
The test signals go into the through-line arm of the couplers, and from there to the test ports and the DUT.
The coupled arm of the couplers carries the signal reflected from or transmitted through the DUT, to the
receiver for measurement (through front panel jumpers), as inputs A, B, C, and D for 4-port models or inputs
A and B for 2-port models. The coupling coefficient of the directional couplers is nominally 15 dB for all
frequencies above 500 MHz. The coupling coefficient increases for frequencies below 500 MHz.
Service Guide N5227-90001 5-21