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laforge, 02/19/2016 10:48 PM
add scope captures from the I/Q baseband output


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= TRF6151C =
This is the Texas Instruments RF Chip TRF6151C

It includes a VCO, Mixers, etc.

TSP

The TSP to the TRF6151 uses three wires: * CLOCK (regular CLK_13M) * STROBE (generated by TPU) * DATA (provided by TPU at falling edge of CLOCK, TRF samples data at rising edge of CLOCK)

[[Image(Rita:trf6151_serial_1.png)]]

[[Image(Rita:trf6151_serial_2.png)]]

The timings have been confirmed by the measurements below:

[[Image(Rita:trf6151_tsp.png)]]

Analog I/Q baseband output

During development I've taken some measurements of the I/Q output of the TRF6151.

The green and black graph of the diagrams below are the "I" channel positive and negative signal.
The magenta graph is the difference signal computed by the Scope.

=== baseband output in idle mode listening on paging channel ===

This is zoomed out to a very long timebae to see the Rx activity at 1.8 second intervals,
which apparently was the paging channel for the paging group of that IMSI.

[[Image(Rita:trf6151_iq_rx_paging_channel.png)]]

=== multiple consecutive bursts ===

This shows multiple consecutive received bursts.
You can see that there is a DC offset when the TRF6151 is powered up, but you can't really see data on that DC offset

[[Image(Rita:trf6151_iq_rx_burst_distance.png)]]

=== a single burst ===

[[Image(Rita:trf6151_rx_iq_one_burst.png)]]

=== bits of a burst ===

[[Image(Rita:trf6151_rx_iq_bits_of_burst.png)]]

Files (5)
trf6151_tsp.png View trf6151_tsp.png 8.15 KB TSP measurements from C123 phone laforge, 01/26/2010 06:58 PM
trf6151_iq_rx_burst_distance.png View trf6151_iq_rx_burst_distance.png 9.01 KB TRF6151 receiving several GSM bursts in sequence laforge, 01/29/2010 11:01 PM
trf6151_iq_rx_paging_channel.png View trf6151_iq_rx_paging_channel.png 6.83 KB I/Q output while listening on the paging channel laforge, 01/29/2010 11:02 PM
trf6151_rx_iq_one_burst.png View trf6151_rx_iq_one_burst.png 8.08 KB I/Q output zoom of one burst laforge, 01/29/2010 11:03 PM
trf6151_rx_iq_bits_of_burst.png View trf6151_rx_iq_bits_of_burst.png 9.59 KB I/Q output zoomed in to see individual bits laforge, 01/29/2010 11:04 PM

Updated by laforge about 8 years ago · 4 revisions

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