diff --git a/VERSION b/VERSION
index 627a3f43..4d0dcda0 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-4.1.1
+4.1.2
diff --git a/libloragw/src/loragw_fpga.c b/libloragw/src/loragw_fpga.c
index 6051d663..fa83a2a9 100644
--- a/libloragw/src/loragw_fpga.c
+++ b/libloragw/src/loragw_fpga.c
@@ -144,6 +144,13 @@ int lgw_fpga_configure(uint32_t tx_notch_freq) {
         return LGW_REG_ERROR;
     }
 
+    /* Required for Semtech AP2 reference design */
+    x  = lgw_fpga_reg_w(LGW_FPGA_CTRL_INVERT_IQ, 1);
+    if (x != LGW_REG_SUCCESS) {
+        DEBUG_MSG("ERROR: Failed to configure FPGA polarity\n");
+        return LGW_REG_ERROR;
+    }
+
     /* Configure TX notch filter */
     if (tx_filter_support == true) {
         notch_offset_reg = (32E6 / (2*tx_notch_freq)) - 64;
diff --git a/libloragw/src/loragw_hal.c b/libloragw/src/loragw_hal.c
index 1edbdb29..7271eac7 100644
--- a/libloragw/src/loragw_hal.c
+++ b/libloragw/src/loragw_hal.c
@@ -69,8 +69,8 @@ Maintainer: Sylvain Miermont
 #define AGC_CMD_WAIT        16
 #define AGC_CMD_ABORT       17
 
-#define MIN_LORA_PREAMBLE   4
-#define STD_LORA_PREAMBLE   6
+#define MIN_LORA_PREAMBLE   6
+#define STD_LORA_PREAMBLE   8
 #define MIN_FSK_PREAMBLE    3
 #define STD_FSK_PREAMBLE    5
 
diff --git a/readme.md b/readme.md
index cfeee0e2..001cfa0a 100644
--- a/readme.md
+++ b/readme.md
@@ -70,6 +70,12 @@ chip through GPIO, before starting any application using the concentrator.
 4. Changelog
 -------------
 
+### v4.1.2 ###
+
+* HAL: Changed configuration of IQ polarity of FPGA for TX to comply with FPGA
+version greater than v27. (Only required for AP2 Semtech reference design)
+* HAL: Updated default LoRa preamble size according to LoRaWAN spec.
+
 ### v4.1.1 ###
 
 * HAL: Fixed bug in "Listen-Before-Talk" which was preventing from configuring