n320: Improve comments regarding low band

The N320 code include some constants that were either unused or
incorrect. This clarifies the lowband frequency.

1 files changed, 6 insertions, 0 deletions

diff --git a/host/lib/usrp/dboard/rhodium/rhodium_bands.cpp b/host/lib/usrp/dboard/rhodium/rhodium_bands.cpp
index 6c16a7d7f..8a41b4b2b 100644
--- a/host/lib/usrp/dboard/rhodium/rhodium_bands.cpp
+++ b/host/lib/usrp/dboard/rhodium/rhodium_bands.cpp
@@ -20,6 +20,9 @@ namespace {
  * The RX path has 8 bands, which we call BAND0 through BAND7. BAND0 is the
  * lowest frequency band. BAND7 is the highest frequency band.
  *
+ * BAND0 is also identical with the "low band", i.e., the frequency range in
+ * which we shift the signal up to an IF before mixing it back down to DC.
+ *
  * The following constants define lower cutoff frequencies for each band.
  * RHODIUM_RX_BAND1_MIN_FREQ is the cutover frequency for switching from
  * BAND0 to BAND1, and so on.
@@ -45,6 +48,9 @@ constexpr double RHODIUM_RX_BAND7_MIN_FREQ = 4500e6;
  * The TX path has 8 bands, which we call BAND0 through BAND7. BAND0 is the
  * lowest frequency band. BAND7 is the highest frequency band.
  *
+ * BAND0 is also identical with the "low band", i.e., the frequency range in
+ * which we shift the signal up to an IF before mixing it back down to DC.
+ *
  * The following constants define lower cutoff frequencies for each band.
  * RHODIUM_TX_BAND1_MIN_FREQ is the cutover frequency for switching from
  * BAND0 to BAND1, and so on.