The E48-900T20S is a cost-effective, industrial-grade wireless data transmission module from Ebyte. It features automatic frequency hopping, automatic packet retransmission, relay networking, air wake-up (WoR), wireless remote configuration, communication key encryption, LBT (Listen Before Talk), and RSSI signal strength indication — all in a compact SMD stamp-hole package.
Technical Specifications
| Electrical Parameter | Unit | Value | Remarks |
| Operating Voltage | V | 2.7 – 5.5 | >3.3 V recommended for guaranteed output power |
| Communication Level | V | 3.3 | Do NOT use 5 V TTL directly — risk of damage |
| TX Current | mA | 110 | Peak @5 V supply |
| RX Current | mA | 12 | @5 V supply |
| Sleep Current | µA | 3.5 | Software shutdown mode |
| Operating Temperature | ℃ | −40 to +85 | Industrial grade |
| RF Parameter | Unit | Value | Remarks |
| Working Frequency | MHz | 855 – 925 | ISM band; covers EU868 & US915 |
| Transmit Power | dBm | 20 ± 1 | Multi-level adjustable via AT command |
| Blocking Power | dBm | 0 – 10 | Reduces burn risk at close range |
| Receive Sensitivity | dBm | −120 ± 2 | @2.4 kbps air rate |
| Air Rate | kbps | 2.4 – 500 | 8 levels, configurable via AT command |
| Measured Range | km | 3.5 | Open field, 3.5 dBi antenna @ 2.5 m height, 2.4 kbps |
| Physical Parameter | Unit | Value | Remarks |
| Dimensions | mm | 26 × 16 | SMD stamp-hole, 1.27 mm pitch |
| Weight | g | 2.0 ± 0.1 | — |
| Antenna Interface | — | IPEX / Stamp Hole | — |
| Modulation | — | GFSK | — |
| Communication Interface | — | UART TTL | 3.3 V logic level |
| Packet Buffer | Byte | 1000 | — |
| Max Packet Length | Byte | 58 / 116 | Configurable via AT command |
Key Features
Automatic Frequency Hopping
The E48-900T20S implements pseudo-random frequency hopping across the 855–925 MHz band, significantly improving anti-interference performance in congested ISM environments. Ideal for deployments near Wi-Fi, Zigbee, or other 900 MHz devices.
Automatic Packet Retransmission
Built-in ARQ (Automatic Repeat reQuest) ensures reliable delivery without host MCU overhead. The module autonomously retransmits lost packets and confirms receipt, reducing application-layer complexity.
Ultra-Low Power & Air Wake-Up (WoR)
Sleep current of only 3.5 µA enables battery-powered deployments. The hardware air wake-up function allows the module to wake from sleep on receiving a valid RF signal, enabling duty-cycled sensor nodes with years of battery life.
Data Encryption & Communication Key
Supports configurable communication keys for link-layer encryption. Ensures data security in multi-node deployments and prevents unauthorized access or eavesdropping.
Automatic Relay Networking
Supports multi-hop relay networking without additional infrastructure. Nodes can automatically forward packets, extending effective range beyond line-of-sight limitations.
LBT (Listen Before Talk) & RSSI
LBT compliance ensures the module checks channel occupancy before transmitting, reducing collisions in dense networks. Real-time RSSI readback enables link quality monitoring and adaptive power control.
Industrial-Grade Design
Rated −40 ℃ to +85 ℃. Passes industrial EMC and ESD standards. SMD stamp-hole packaging with 1.27 mm pitch ensures reliable reflow soldering and mechanical stability in vibration-prone environments.
Ideal Applications
Ordering Options
| SKU | Contents | Antenna |
| E48-900T20S | Module only | IPEX connector (antenna not included) |
| E48-900T20S + TX915-FPC-8521 | Module + FPC antenna | 915 MHz flexible PCB antenna |
| E48-900T20S + TX915-JKS-IPX20 | Module + external antenna | 915 MHz IPEX omnidirectional antenna, 20 cm cable |
FAQ
Q: What is the difference between frequency hopping and LoRa spread spectrum?
A: The E48-900T20S uses GFSK modulation with automatic frequency hopping (FHSS), which rapidly switches carrier frequency to avoid interference. LoRa uses chirp spread spectrum (CSS) for longer range at lower data rates. GFSK/FHSS offers higher throughput (up to 500 kbps) and lower latency, making it better suited for real-time telemetry and control applications.
Q: How do I configure the module?
A: Configuration is done via UART AT commands using Ebyte's free RF Setting Tool (Windows). Parameters include frequency channel, air rate, TX power, packet length, WoR period, communication key, and relay mode. Remote wireless configuration is also supported without physical access to deployed nodes.
Q: Is the E48-900T20S compatible with LoRaWAN networks (TTN, Helium)?
A: No. The E48-900T20S uses proprietary GFSK/FHSS protocol for point-to-point, point-to-multipoint, and relay topologies. It is not LoRaWAN compatible. For LoRaWAN applications, please refer to the Ebyte E22 or E77 series.
Q: What is the maximum communication distance?
A: 3.5 km measured in open field conditions with 3.5 dBi antennas at 2.5 m height and 2.4 kbps air rate. Actual range depends on environment, antenna gain, air rate setting, and obstacles. Urban or indoor deployments will be shorter.
Q: Can I use 5 V TTL directly with this module?
A: No. The communication logic level is 3.3 V. Applying 5 V TTL directly to the UART pins risks permanent damage. Use a level shifter if your MCU operates at 5 V. The power supply (VCC) can accept 2.7–5.5 V.
