diff --git a/.vscode/settings.json b/.vscode/settings.json
index b5629450e0dc..f2c42d5328b9 100644
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -9,7 +9,8 @@
         "Makefile.*": "makefile",
         "*.mk": "makefile",
         "kernel_defines.h": "c",
-        "sx126x_internal.h": "c"
+        "sx126x_internal.h": "c",
+        "submac.h": "c"
     },
     "[shellscript][c][cpp]": {
         "editor.tabSize": 4,
diff --git a/boards/rak3172/Makefile.features b/boards/rak3172/Makefile.features
index 42d19682ebeb..51bf625975c1 100644
--- a/boards/rak3172/Makefile.features
+++ b/boards/rak3172/Makefile.features
@@ -12,3 +12,6 @@ FEATURES_PROVIDED += periph_uart
 
 # Put other features for this board (in alphabetical order)
 FEATURES_PROVIDED += riotboot
+
+CFLAGS += -DCONFIG_IEEE802154_DEFAULT_SUBGHZ_CHANNEL=5
+CFLAGS += -DCONFIG_IEEE802154_DEFAULT_TXPOWER=22
diff --git a/boards/rak3172/include/board.h b/boards/rak3172/include/board.h
index da1a689545ca..70922a5a9102 100644
--- a/boards/rak3172/include/board.h
+++ b/boards/rak3172/include/board.h
@@ -39,7 +39,6 @@ extern "C" {
 extern void lora_e5_dev_sx126x_set_rf_mode(sx126x_t *dev, sx126x_rf_mode_t rf_mode);
 #define SX126X_PARAM_SET_RF_MODE_CB         lora_e5_dev_sx126x_set_rf_mode
 #define SX126X_PARAM_TYPE                   SX126X_TYPE_STM32WL
-#define CONFIG_SX126X_TX_POWER_DEFAULT		(22)
 #endif
 /** @} */
 
diff --git a/drivers/sx126x/sx126x_radio_hal.c b/drivers/sx126x/sx126x_radio_hal.c
index 2551e8164639..14477e20df37 100644
--- a/drivers/sx126x/sx126x_radio_hal.c
+++ b/drivers/sx126x/sx126x_radio_hal.c
@@ -39,14 +39,13 @@
 #include "sx126x_params.h"
 #include "sx126x_internal.h"
 
-#define LORA_ACK_REPLY_US          1024
+#define LORA_ACK_REPLY_US          100
 
-#define SX126X_HAL_CHAN_26 (869525000LU)
-#define SX126X_HAL_CHAN_BASE (865500000LU)
+#define SX126X_HAL_CHAN_BASE (868100000LU)
 #define SX126X_HAL_CHAN_SPACING (200000LU)
 
-#define SX126X_CHAN_MIN (11)
-#define SX126X_CHAN_MAX (26)
+#define SX126X_CHAN_MIN (IEEE802154_CHANNEL_MIN_SUBGHZ)
+#define SX126X_CHAN_MAX (8)
 
 #define SX126X_POWER_MIN (-9)
 #define SX126X_POWER_MAX (22)
@@ -80,7 +79,7 @@ void isr_subghz_radio(void)
     /* Disable NVIC to avoid ISR conflict in CPU. */
     NVIC_DisableIRQ(SUBGHZ_Radio_IRQn);
     NVIC_ClearPendingIRQ(SUBGHZ_Radio_IRQn);
-    event_post(EVENT_PRIO_HIGHEST, &sx126x_ev);
+    event_post(EVENT_PRIO_MEDIUM, &sx126x_ev);
     cortexm_isr_end();
 }
 #endif 
@@ -412,7 +411,7 @@ switch (op){
        if (info) {
             info->status = (dev->cad_detected) ? TX_STATUS_MEDIUM_BUSY : TX_STATUS_SUCCESS;
         }
-    while(state == STATE_TX)
+
         _get_state(dev, &state);
         
     break;
@@ -438,7 +437,7 @@ switch (op){
 }
 
     if (eagain) {
-        DEBUG("EAGAIN");
+       
         return -EAGAIN;
     }
 
@@ -503,16 +502,10 @@ static int _config_phy(ieee802154_dev_t *hal, const ieee802154_phy_conf_t *conf)
     sx126x_t *dev = hal->priv;
     uint8_t channel = conf->channel;
     int8_t pow = conf->pow;
-    if((channel < SX126X_CHAN_MIN) && (channel > SX126X_CHAN_MAX))
+    if((channel > SX126X_CHAN_MAX))
         return -EINVAL;
-
-    if (channel == 26) {
-        sx126x_set_channel(dev, SX126X_HAL_CHAN_26);
-    }
-    else {
-        sx126x_set_channel(dev, (channel-11)*SX126X_HAL_CHAN_SPACING + SX126X_HAL_CHAN_BASE);
-    }
-
+    
+    sx126x_set_channel(dev, (channel)*SX126X_HAL_CHAN_SPACING + SX126X_HAL_CHAN_BASE);
     if((pow < SX126X_POWER_MIN) && (pow > SX126X_POWER_MAX))
         return -EINVAL;
 
@@ -628,7 +621,7 @@ static int _set_csma_params(ieee802154_dev_t *hal, const ieee802154_csma_be_t *b
 
 
 static const ieee802154_radio_ops_t sx126x_ops = {
-    .caps =  IEEE802154_CAP_24_GHZ
+    .caps =  IEEE802154_CAP_SUB_GHZ
           | IEEE802154_CAP_IRQ_CRC_ERROR
           | IEEE802154_CAP_IRQ_RX_START
           | IEEE802154_CAP_IRQ_TX_DONE
diff --git a/sys/include/net/ieee802154.h b/sys/include/net/ieee802154.h
index 5b4393502d83..5d14655c2582 100644
--- a/sys/include/net/ieee802154.h
+++ b/sys/include/net/ieee802154.h
@@ -550,6 +550,16 @@ static inline uint8_t ieee802154_dbm_to_rssi(int16_t dbm)
     return val - IEEE802154_RADIO_RSSI_OFFSET;
 }
 
+/**
+ * @brief Get the symbol time for a given PHY channel.
+ *
+ * @param[in] channel_page channel page
+ * @param[in] channel_num channel number
+ *
+ * @return the symbol time in us
+ */
+uint32_t ieee802154_get_symbol_time(uint8_t channel_page, uint16_t channel_num);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/sys/net/link_layer/ieee802154/ieee802154.c b/sys/net/link_layer/ieee802154/ieee802154.c
index 9d51bc815843..3929bf6dd70c 100644
--- a/sys/net/link_layer/ieee802154/ieee802154.c
+++ b/sys/net/link_layer/ieee802154/ieee802154.c
@@ -19,6 +19,32 @@
 
 #include "net/ieee802154.h"
 
+#define ENABLE_DEBUG 0
+#include "debug.h"
+
+#define CHANNEL_868MHZ          (0U) /**< channel associated to the 868 MHz band */
+
+/**
+ * @brief O-QPSK symbol time definition
+ * @see IEEE 802.15.4-2015 standard, section 12.3.3
+ */
+#define SYMTIME_OQPSK_868MHZ    (40U) /**< 25 ksymbols/s */
+#define SYMTIME_OQPSK_COMMON    (16U) /**< 62.5 ksymbols/s */
+
+/**
+ * @brief BPSK symbol time definition
+ * @see IEEE 802.15.4-2015 standard, section 13.3.3
+ */
+#define SYMTIME_BPSK_868MHZ     (50U) /**< 20 ksymbols/s */
+#define SYMTIME_BPSK_COMMON     (25U) /**< 40 ksymbols/s */
+
+/**
+ * @brief ASK symbol time definition
+ * @see IEEE 802.15.4-2015 standard, section 14.4.3
+ */
+#define SYMTIME_ASK_868MHZ      (80U) /**< 12.5 ksymbols/s */
+#define SYMTIME_ASK_COMMON      (20U) /**< 50 ksymbols/s */
+
 const uint8_t ieee802154_addr_bcast[IEEE802154_ADDR_BCAST_LEN] = IEEE802154_ADDR_BCAST;
 
 size_t ieee802154_set_frame_hdr(uint8_t *buf, const uint8_t *src, size_t src_len,
@@ -281,4 +307,58 @@ int ieee802154_dst_filter(const uint8_t *mhr, uint16_t pan,
     return 1;
 }
 
+static inline uint8_t _get_oqpsk_symbol_time(uint16_t channel)
+{
+    if (channel == CHANNEL_868MHZ) {
+        return SYMTIME_OQPSK_868MHZ;
+    }
+    return SYMTIME_OQPSK_COMMON;
+}
+
+static inline uint8_t _get_ask_symbol_time(uint16_t channel)
+{
+    if (channel == CHANNEL_868MHZ) {
+        return SYMTIME_ASK_868MHZ;
+    }
+    return SYMTIME_ASK_COMMON;
+}
+
+static inline uint8_t _get_bpsk_symbol_time(uint16_t channel)
+{
+    if (channel == CHANNEL_868MHZ) {
+        return SYMTIME_BPSK_868MHZ;
+    }
+    return SYMTIME_BPSK_COMMON;
+}
+
+uint32_t ieee802154_get_symbol_time(uint8_t channel_page, uint16_t channel_num)
+{
+    /* BPSK for SubGHZ, O-QPSK for 2.4 GHz (see IEEE 802.15.4-2015 standard, section 10.1.2.2) */
+    if (channel_page == 0) {
+        if (channel_num <= IEEE802154_CHANNEL_MAX_SUBGHZ) {
+            return _get_bpsk_symbol_time(channel_num);
+        }
+        else {
+            return _get_oqpsk_symbol_time(channel_num);
+        }
+    }
+    /* ASK for SubGHZ (see IEEE 802.15.4-2015 standard, section 10.1.2.2) */
+    else if (channel_page == 1) {
+        if (channel_num <= IEEE802154_CHANNEL_MAX_SUBGHZ) {
+            return _get_ask_symbol_time(channel_num);
+        }
+    }
+    /* O-QPSK for SubGHZ (see IEEE 802.15.4-2015 standard, section 10.1.2.2) */
+    else if (channel_page == 2) {
+        if (channel_num <= IEEE802154_CHANNEL_MAX_SUBGHZ) {
+            return _get_oqpsk_symbol_time(channel_num);
+        }
+    }
+    /* add more channel pages as needed */
+
+    DEBUG("[ieee802154]: ieee802154_get_symbol_time: invalid PHY config or PHY not implemented");
+    assert(false);
+    return 0;
+}
+
 /** @} */
diff --git a/sys/net/link_layer/ieee802154/submac.c b/sys/net/link_layer/ieee802154/submac.c
index c04e1692f826..56f2eb873349 100644
--- a/sys/net/link_layer/ieee802154/submac.c
+++ b/sys/net/link_layer/ieee802154/submac.c
@@ -27,9 +27,9 @@
 #define ENABLE_DEBUG 0
 #include "debug.h"
 
-#define CSMA_SENDER_BACKOFF_PERIOD_UNIT_US  (320U)
-//#define ACK_TIMEOUT_US                      (864U)
-#define ACK_TIMEOUT_US                      (50000U)
+#define CSMA_SENDER_BACKOFF_PERIOD_UNIT_US   (320U)
+#define ACK_TIMEOUT_SYMS                     (54U)
+
 static char *str_states[IEEE802154_FSM_STATE_NUMOF] = {
     "INVALID",
     "RX",
@@ -282,7 +282,9 @@ static ieee802154_fsm_state_t _fsm_state_tx_process_tx_done(ieee802154_submac_t
             assert (res >= 0);
 
             /* Handle ACK reception */
-            ieee802154_submac_ack_timer_set(submac, ACK_TIMEOUT_US);
+            uint8_t symbol_time = ieee802154_get_symbol_time(submac->channel_page,
+                                                             submac->channel_num);
+            ieee802154_submac_ack_timer_set(submac, symbol_time * ACK_TIMEOUT_SYMS);
             return IEEE802154_FSM_STATE_WAIT_FOR_ACK;
         }
         break;