diff --git a/drivers/net/wireless/ath/ath9k/ar9003_phy.c b/drivers/net/wireless/ath/ath9k/ar9003_phy.c
index be6069bc48319b747a03bc5fce841fe509fe5df0..4c8d0d7709456c987d3de9c051c207f45fa86a0d 100644
--- a/drivers/net/wireless/ath/ath9k/ar9003_phy.c
+++ b/drivers/net/wireless/ath/ath9k/ar9003_phy.c
@@ -728,6 +728,10 @@ static void ar9003_hw_set_rfmode(struct ath_hw *ah,
 	if (IS_CHAN_HALF_RATE(chan))
 		rfMode |= AR_PHY_MODE_HALF;
 
+	if (rfMode & (AR_PHY_MODE_QUARTER | AR_PHY_MODE_HALF))
+		REG_RMW_FIELD(ah, AR_PHY_FRAME_CTL,
+			      AR_PHY_FRAME_CTL_CF_OVERLAP_WINDOW, 3);
+
 	REG_WRITE(ah, AR_PHY_MODE, rfMode);
 }
 
diff --git a/drivers/net/wireless/ath/ath9k/ar9003_phy.h b/drivers/net/wireless/ath/ath9k/ar9003_phy.h
index d834d97fe7276e279402d4e3a75e6e6db1ac983f..7268a48a92a178c95c953ffa3e0bbbfcc2fe3627 100644
--- a/drivers/net/wireless/ath/ath9k/ar9003_phy.h
+++ b/drivers/net/wireless/ath/ath9k/ar9003_phy.h
@@ -468,6 +468,9 @@
 #define AR_PHY_ADDAC_PARA_CTL    (AR_SM_BASE + 0x150)
 #define AR_PHY_XPA_CFG           (AR_SM_BASE + 0x158)
 
+#define AR_PHY_FRAME_CTL_CF_OVERLAP_WINDOW  3
+#define AR_PHY_FRAME_CTL_CF_OVERLAP_WINDOW_S    0
+
 #define AR_PHY_SPUR_MASK_A_CF_PUNC_MASK_IDX_A           0x0001FC00
 #define AR_PHY_SPUR_MASK_A_CF_PUNC_MASK_IDX_A_S         10
 #define AR_PHY_SPUR_MASK_A_CF_PUNC_MASK_A                       0x3FF