diff --git a/src/main.c b/src/main.c
index df16830..b35603b 100644
--- a/src/main.c
+++ b/src/main.c
@@ -62,9 +62,11 @@ static uint32_t lo_phase[LO_NUM_PHASES][LO_PHASE_WORDS]
 static uint32_t nco_addr = (uint32_t)lo_phase;
 
 #define DECIMATE 16
-#define RX_BITS_DEPTH 10
+#define RX_BITS_DEPTH 8
 #define RX_WORDS (1 << (RX_BITS_DEPTH - 2))
 
+static_assert(RX_WORDS >= 4 * DECIMATE, "RX_WORDS >= 4 * DECIMATE");
+
 static uint32_t rx_cos[RX_WORDS] __attribute__((__aligned__(1 << RX_BITS_DEPTH)));
 
 static const uint32_t *rx_start = rx_cos;