TIDA029A Application note

TIDA029A july 2019 – june 2023 CC2640R2F-Q1 , CC2642R , CC2642R-Q1

4.2.1 Bare PCB AoA With Compensation

The bare PCB required the least amount of compensation as the results were fairly close to Phi. However, Table 4-1 shows the gain and offset values used for each frequency.

Table 4-1 Bare PCB AoA Compensation Values

Frequency (MHz)	Channel	Gain	Offset
2402	37	1.12	–4.69
2404	0	1.12	–4.69
2406	1	1.12	–5.04
2408	2	1.14	–4.82
2410	3	1.14	–4.82
2412	4	1.14	–5.1
2414	5	1.15	–4.81
2416	6	1.15	–4.73
2418	7	1.15	–4.45
2420	8	1.15	–4.73
2422	9	1.15	–4.16
2424	10	1.15	–4.37
2426	38	1.15	–4.22
2428	11	1.15	–4.36
2430	12	1.15	–3.86
2432	13	1.14	–3.65
2434	14	1.14	–3.72
2436	15	1.15	–3.57
2438	16	1.14	–3.43
2440	17	1.14	–3.29
2442	18	1.14	–2.93
2444	19	1.12	–3
2446	20	1.12	–2.09
2448	21	1.12	–2.79
2450	22	1.12	–2.65
2452	23	1.12	–2.57
2454	24	1.12	–2.64
2456	25	1.12	–2.36
2458	26	1.12	–2.64
2460	27	1.12	–2.36
2462	28	1.12	–2.08
2464	29	1.11	–2.49
2466	30	1.11	–2.35
2468	31	1.11	–2.63
2470	32	1.11	–2.14
2472	33	1.11	–2.55
2474	34	1.11	–2.41
2476	35	1.11	–2.07
2478	36	1.11	–1.86
2480	39	1.09	–1.99

Figure 4-14 shows the uncompensated AoA error vs Phi (the actual angle) and Figure 4-15 the compensated AoA error vs Phi.

Figure 4-14 Bare PCB Uncompensated AoA Error Results

Figure 4-15 Bare PCB Compensated AoA Error Results

It is clear that the error is greatly reduced over the most linear range (–65° to 65°). Figure 4-16 and Figure 4-17 show how the results have been adjusted to follow the ideal AoA vs Phi plot. There is less than 10° of error across the majority of frequencies from –70° to 65°.

Figure 4-16 Bare PCB Uncompensated AoA Results Over all Bluetooth Low Energy Channels

Figure 4-17 Bare PCB Compensated AoA Results Over all Bluetooth Low Energy Channels