Data Sheet

ADA8282

Rev. 0 | Page 13 of 21

CHANNEL TO CHANNEL PHASE MATCHING

In a multichannel radar application, matching the ac performance

between channels improves the distance and angle resolution of

a detected object, particularly the phase matching in the band of

interest for the application. The ADA8282 layout and design are

optimized to increase phase matching. The ADA8282 also has

sufficient bandwidth to minimize any channel to channel phase

variation for up to 5 MHz input signals.

The phase mismatch between channels can be calibrated at a

single temperature. However, any variation in phase matching

over temperature can still degrade system performance. The

ADA8282 is characterized to capture the maximum channel to

channel phase mismatch as the temperature varies from a

calibration temperature of 25°C.

Figure 27 shows a distribution of channel to channel phase

mismatch for signal frequencies up to 5 MHz. When the initial

phase mismatch between channels is normalized to 0° at +25°C,

the 6σ mismatch is 0.43° at −40°C and 0.6° at +125°C.

350

300

250

200

150

100

50

0

PHASE MISMATCH (Degrees)

Figure 27. Channel to Channel Phase Mismatch, Normalized to 0° at 25°C,

LNA_BIAS_SEL = PGA_BIAS_SEL = b’00, PGA_GAIN = b’11

The amount of channel to channel phase mismatch varies with

the power mode. Table 10 shows the 6σ phase mismatch up to

5 MHz over the full temperature range for all gain settings in

different power modes, when normalized to 0° at 25°C in each

power mode.

Table 10. Maximum Channel to Channel Phase Mismatch over Temperature After 25°C Calibration

PGA_BIAS_SEL

LNA_BIAS_SEL

6σ Channel to Channel Phase Mismatch

over Temperature (Degrees)

Maximum Channel to Channel Phase

Mismatch (Degrees)

b’00

b’00

0.60

±1

b’01

b’01

0.41

±1

b’10

b’10

0.33

±1

b’11

b’11

0.60

±1