Rita » History » Version 5
laforge, 02/19/2016 10:48 PM
1 | 4 | laforge | [[PageOutline]] |
---|---|---|---|
2 | 4 | laforge | |
3 | 4 | laforge | = TRF6151C = |
4 | 1 | laforge | This is the Texas Instruments RF Chip TRF6151C |
5 | 1 | laforge | |
6 | 1 | laforge | It includes a VCO, Mixers, etc. |
7 | 2 | laforge | |
8 | 2 | laforge | == TSP == |
9 | 2 | laforge | |
10 | 2 | laforge | The TSP to the TRF6151 uses three wires: |
11 | 2 | laforge | * CLOCK (regular CLK_13M) |
12 | 2 | laforge | * STROBE (generated by TPU) |
13 | 2 | laforge | * DATA (provided by TPU at falling edge of CLOCK, TRF samples data at rising edge of CLOCK) |
14 | 2 | laforge | |
15 | 3 | laforge | [[Image(Rita:trf6151_tsp.png)]] |
16 | 4 | laforge | |
17 | 4 | laforge | == Analog I/Q baseband output == |
18 | 4 | laforge | |
19 | 4 | laforge | During development I've taken some measurements of the I/Q output of the TRF6151. |
20 | 4 | laforge | |
21 | 4 | laforge | The green and black graph of the diagrams below are the "I" channel positive and negative signal. |
22 | 4 | laforge | The magenta graph is the difference signal computed by the Scope. |
23 | 4 | laforge | |
24 | 4 | laforge | === baseband output in idle mode listening on paging channel === |
25 | 4 | laforge | |
26 | 4 | laforge | This is zoomed out to a very long timebae to see the Rx activity at 1.8 second intervals, |
27 | 4 | laforge | which apparently was the paging channel for the paging group of that IMSI. |
28 | 4 | laforge | |
29 | 4 | laforge | [[Image(Rita:trf6151_iq_rx_paging_channel.png)]] |
30 | 4 | laforge | |
31 | 4 | laforge | === multiple consecutive bursts === |
32 | 4 | laforge | |
33 | 4 | laforge | This shows multiple consecutive received bursts. |
34 | 4 | laforge | 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 |
35 | 4 | laforge | |
36 | 4 | laforge | [[Image(Rita:trf6151_iq_rx_burst_distance.png)]] |
37 | 4 | laforge | |
38 | 4 | laforge | === a single burst === |
39 | 4 | laforge | |
40 | 4 | laforge | [[Image(Rita:trf6151_rx_iq_one_burst.png)]] |
41 | 4 | laforge | |
42 | 4 | laforge | === bits of a burst === |
43 | 4 | laforge | |
44 | 4 | laforge | [[Image(Rita:trf6151_rx_iq_bits_of_burst.png)]] |