diff --git a/core/rtw_mp.c b/core/rtw_mp.c
index 73ee0bf..a709f0d 100644
--- a/core/rtw_mp.c
+++ b/core/rtw_mp.c
@@ -1819,11 +1819,11 @@ static inline void dump_buf(u8 *buf, u32 len)
 }
 
 void ByteToBit(
-	UCHAR	*out,
+	u8	*out,
 	bool	*in,
-	UCHAR	in_size)
+	u8	in_size)
 {
-	UCHAR i = 0, j = 0;
+	u8 i = 0, j = 0;
 
 	for (i = 0; i < in_size; i++) {
 		for (j = 0; j < 8; j++) {
@@ -1837,10 +1837,10 @@ void ByteToBit(
 void CRC16_generator(
 	bool *out,
 	bool *in,
-	UCHAR in_size
+	u8 in_size
 )
 {
-	UCHAR i = 0;
+	u8 i = 0;
 	bool temp = 0, reg[] = {1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1};
 
 	for (i = 0; i < in_size; i++) {/* take one's complement and bit reverse*/
@@ -1885,7 +1885,7 @@ void CCK_generator(
 	bool LengthExtBit;
 	double LengthExact;
 	double LengthPSDU;
-	UCHAR i;
+	u8 i;
 	UINT PacketLength = pPMacTxInfo->PacketLength;
 
 	if (pPMacTxInfo->bSPreamble)
@@ -1957,8 +1957,8 @@ void PMAC_Get_Pkt_Param(
 	PRT_PMAC_PKT_INFO	pPMacPktInfo)
 {
 
-	UCHAR		TX_RATE_HEX = 0, MCS = 0;
-	UCHAR		TX_RATE = pPMacTxInfo->TX_RATE;
+	u8		TX_RATE_HEX = 0, MCS = 0;
+	u8		TX_RATE = pPMacTxInfo->TX_RATE;
 
 	/*	TX_RATE & Nss	*/
 	if (MPT_IS_2SS_RATE(TX_RATE))
@@ -2109,7 +2109,7 @@ void PMAC_Nsym_generator(
 	PRT_PMAC_PKT_INFO	pPMacPktInfo)
 {
 	UINT	SIGA2B3 = 0;
-	UCHAR	TX_RATE = pPMacTxInfo->TX_RATE;
+	u8	TX_RATE = pPMacTxInfo->TX_RATE;
 
 	UINT R, R_list[10] = {0, 0, 2, 0, 2, 1, 2, 3, 2, 3};
 	double CR = 0;
@@ -2127,7 +2127,7 @@ void PMAC_Nsym_generator(
 		N_SD = 234;
 
 	if (MPT_IS_HT_RATE(TX_RATE)) {
-		UCHAR MCS_temp;
+		u8 MCS_temp;
 
 		if (pPMacPktInfo->MCS > 23)
 			MCS_temp = pPMacPktInfo->MCS - 24;
@@ -2268,7 +2268,7 @@ void L_SIG_generator(
 		mode = pPMacPktInfo->MCS;
 		LENGTH = pPMacTxInfo->PacketLength;
 	} else {
-		UCHAR	N_LTF;
+		u8	N_LTF;
 		double	T_data;
 		UINT	OFDM_symbol;
 
@@ -2374,10 +2374,10 @@ void L_SIG_generator(
 void CRC8_generator(
 	bool	*out,
 	bool	*in,
-	UCHAR	in_size
+	u8	in_size
 )
 {
-	UCHAR i = 0;
+	u8 i = 0;
 	bool temp = 0, reg[] = {1, 1, 1, 1, 1, 1, 1, 1};
 
 	for (i = 0; i < in_size; i++) { /* take one's complement and bit reverse*/
diff --git a/include/basic_types.h b/include/basic_types.h
index bd2d7b9..64c65a7 100644
--- a/include/basic_types.h
+++ b/include/basic_types.h
@@ -47,7 +47,7 @@
 
 	typedef	signed int sint;
 
-	#define UCHAR u8
+	#define u8 u8
 	#define USHORT u16
 	#define UINT u32
 	#define ULONG u32
diff --git a/include/ethernet.h b/include/ethernet.h
index e127605..c688337 100644
--- a/include/ethernet.h
+++ b/include/ethernet.h
@@ -28,14 +28,14 @@
 #define MINIMUM_ETHERNET_PACKET_SIZE		60		/* !< Minimum Ethernet Packet Size */
 #define MAXIMUM_ETHERNET_PACKET_SIZE		1514	/* !< Maximum Ethernet Packet Size */
 
-#define RT_ETH_IS_MULTICAST(_pAddr)	((((UCHAR *)(_pAddr))[0]&0x01) != 0)		/* !< Is Multicast Address? */
+#define RT_ETH_IS_MULTICAST(_pAddr)	((((u8 *)(_pAddr))[0]&0x01) != 0)		/* !< Is Multicast Address? */
 #define RT_ETH_IS_BROADCAST(_pAddr)	(\
-		((UCHAR *)(_pAddr))[0] == 0xff	&&		\
-		((UCHAR *)(_pAddr))[1] == 0xff	&&		\
-		((UCHAR *)(_pAddr))[2] == 0xff	&&		\
-		((UCHAR *)(_pAddr))[3] == 0xff	&&		\
-		((UCHAR *)(_pAddr))[4] == 0xff	&&		\
-		((UCHAR *)(_pAddr))[5] == 0xff)	/* !< Is Broadcast Address? */
+		((u8 *)(_pAddr))[0] == 0xff	&&		\
+		((u8 *)(_pAddr))[1] == 0xff	&&		\
+		((u8 *)(_pAddr))[2] == 0xff	&&		\
+		((u8 *)(_pAddr))[3] == 0xff	&&		\
+		((u8 *)(_pAddr))[4] == 0xff	&&		\
+		((u8 *)(_pAddr))[5] == 0xff)	/* !< Is Broadcast Address? */
 
 
 #endif /*  #ifndef __INC_ETHERNET_H */
diff --git a/include/rtw_bt_mp.h b/include/rtw_bt_mp.h
index 0096c61..c257a7f 100644
--- a/include/rtw_bt_mp.h
+++ b/include/rtw_bt_mp.h
@@ -201,16 +201,16 @@ void mptbt_BtControlProcess(
 #define	BT_MAX_C2H_LEN								20
 
 typedef struct _BT_REQ_CMD {
-	UCHAR       opCodeVer;
-	UCHAR       OpCode;
+	u8       opCodeVer;
+	u8       OpCode;
 	USHORT      paraLength;
-	UCHAR       pParamStart[100];
+	u8       pParamStart[100];
 } BT_REQ_CMD, *PBT_REQ_CMD;
 
 typedef struct _BT_RSP_CMD {
 	USHORT      status;
 	USHORT      paraLength;
-	UCHAR       pParamStart[100];
+	u8       pParamStart[100];
 } BT_RSP_CMD, *PBT_RSP_CMD;
 
 
diff --git a/include/rtw_mp.h b/include/rtw_mp.h
index da233ed..e63ac61 100644
--- a/include/rtw_mp.h
+++ b/include/rtw_mp.h
@@ -106,18 +106,17 @@ struct mp_tx {
 #define s8Byte		s64
 #define ps8Byte		s64*
 
-#define UCHAR u8
 #define USHORT u16
 #define UINT u32
 #define ULONG u32
 #define PULONG u32*
 
 typedef struct _RT_PMAC_PKT_INFO {
-	UCHAR			MCS;
-	UCHAR			Nss;
-	UCHAR			Nsts;
+	u8			MCS;
+	u8			Nss;
+	u8			Nsts;
 	UINT			N_sym;
-	UCHAR			SIGA2B3;
+	u8			SIGA2B3;
 } RT_PMAC_PKT_INFO, *PRT_PMAC_PKT_INFO;
 
 typedef struct _RT_PMAC_TX_INFO {
diff --git a/include/wlan_bssdef.h b/include/wlan_bssdef.h
index 79d1af3..c0f9d14 100644
--- a/include/wlan_bssdef.h
+++ b/include/wlan_bssdef.h
@@ -37,7 +37,7 @@ typedef unsigned long long NDIS_802_11_KEY_RSC;
 
 typedef struct _NDIS_802_11_SSID {
 	ULONG  SsidLength;
-	UCHAR  Ssid[32];
+	u8  Ssid[32];
 } NDIS_802_11_SSID, *PNDIS_802_11_SSID;
 
 typedef enum _NDIS_802_11_NETWORK_TYPE {
@@ -77,15 +77,15 @@ typedef enum _NDIS_802_11_NETWORK_INFRASTRUCTURE {
 } NDIS_802_11_NETWORK_INFRASTRUCTURE, *PNDIS_802_11_NETWORK_INFRASTRUCTURE;
 
 typedef struct _NDIS_802_11_FIXED_IEs {
-	UCHAR  Timestamp[8];
+	u8  Timestamp[8];
 	USHORT  BeaconInterval;
 	USHORT  Capabilities;
 } NDIS_802_11_FIXED_IEs, *PNDIS_802_11_FIXED_IEs;
 
 typedef struct _NDIS_802_11_VARIABLE_IEs {
-	UCHAR  ElementID;
-	UCHAR  Length;
-	UCHAR  data[1];
+	u8  ElementID;
+	u8  Length;
+	u8  data[1];
 } NDIS_802_11_VARIABLE_IEs, *PNDIS_802_11_VARIABLE_IEs;
 
 /*
@@ -171,7 +171,7 @@ typedef struct _NDIS_802_11_KEY {
 	ULONG           KeyLength;          /* length of key in bytes */
 	NDIS_802_11_MAC_ADDRESS BSSID;
 	NDIS_802_11_KEY_RSC KeyRSC;
-	UCHAR           KeyMaterial[32];     /* variable length depending on above field */
+	u8           KeyMaterial[32];     /* variable length depending on above field */
 } NDIS_802_11_KEY, *PNDIS_802_11_KEY;
 
 typedef struct _NDIS_802_11_REMOVE_KEY {
@@ -184,7 +184,7 @@ typedef struct _NDIS_802_11_WEP {
 	ULONG     Length;        /* Length of this structure */
 	ULONG     KeyIndex;      /* 0 is the per-client key, 1-N are the global keys */
 	ULONG     KeyLength;     /* length of key in bytes */
-	UCHAR     KeyMaterial[16];/* variable length depending on above field */
+	u8     KeyMaterial[16];/* variable length depending on above field */
 } NDIS_802_11_WEP, *PNDIS_802_11_WEP;
 
 typedef struct _NDIS_802_11_AUTHENTICATION_REQUEST {
@@ -258,7 +258,7 @@ typedef struct _WLAN_BCN_INFO {
 typedef struct _WLAN_BSSID_EX {
 	ULONG  Length;
 	NDIS_802_11_MAC_ADDRESS  MacAddress;
-	UCHAR  Reserved[2];/* [0]: IS beacon frame */
+	u8  Reserved[2];/* [0]: IS beacon frame */
 	NDIS_802_11_SSID  Ssid;
 	ULONG  Privacy;
 	NDIS_802_11_RSSI  Rssi;/* (in dBM,raw data ,get from PHY) */
@@ -268,7 +268,7 @@ typedef struct _WLAN_BSSID_EX {
 	NDIS_802_11_RATES_EX  SupportedRates;
 	WLAN_PHY_INFO	PhyInfo;
 	ULONG  IELength;
-	UCHAR  IEs[MAX_IE_SZ];	/* (timestamp, beacon interval, and capability information) */
+	u8  IEs[MAX_IE_SZ];	/* (timestamp, beacon interval, and capability information) */
 }
 __attribute__((packed))
 WLAN_BSSID_EX, *PWLAN_BSSID_EX;