LoRa point-to-point transmission scheme is a wireless direct connection communication mode based on LoRa modulation technology, where two end devices directly interact with each other without relying on gateways or cloud servers. Its core is to utilize the long-range and low power consumption characteristics of LoRa to meet the communication needs in specific scenarios while simplifying the network architecture.
Technical realization principle
Hardware architecture
The device needs to be equipped with a LoRa RF chip (e.g. SX1276/SX1262) and configured with the same communication parameters:
Frequency band: choose ISM band such as 433MHz, 868MHz or 915MHz according to the region
Spreading Factor (SF): 7-12 levels adjustable, the higher the SF the longer the transmission distance but the lower the rate
Bandwidth (BW): 125kHz/250kHz/500kHz, the wider the bandwidth, the worse the anti-interference.
Coding Rate (CR): 4/5 to 4/8, affects the error correction capability.
Protocol Design
Customized data frame: define leading code, sync word, load data and CRC check bit
Channel Attendant (CAD): detects channel idleness before sending to avoid collision.
ACK acknowledgement mechanism: the receiver returns an acknowledgement signal after successful decoding to ensure data reliability.
Typical Application Scenarios
Industrial equipment inspection
In a petrochemical plant, an explosion-proof inspection robot sends gas concentration data to a control room 500 meters away in real time via LoRa point-to-point transmission, bypassing the signal shielding problem of metal pipelines.
Agricultural environment monitoring
Soil sensors in agricultural fields are directly connected to irrigation controllers, automatically triggering water pumps when humidity falls below a threshold, without relying on cellular network coverage.
Emergency Communication System
At the earthquake rescue site, the search and rescue equipment establishes a temporary communication link with the command vehicle and transmits the data of the life detector. The communication distance can reach 3 kilometers (SF=12, BW=125kHz).
Performance boundaries and optimization
Transmission distance limits
Urban environments: 1-2 kilometers (subject to building obstructions)
Suburban environment: 5-10 kilometers (under line-of-sight conditions)
Maritime environment: 15+ kilometers (unobstructed scenarios)
Power consumption control
Adopts duty cycle mechanism: the device is in sleep mode 95% of the time (power consumption 0.2μA), and wakes up for communication only in a preset time window. Single 18650 battery can support 3-5 years of battery life.
Anti-jamming program
Dynamic frequency hopping: automatic switching between 10 preset channels
RSSI threshold filtering: discards packets with signal strength below -120dBm
Forward Error Correction (FEC): Recovers corrupted data through coding rate 4/8
Comparison with LoRaWAN
| Dimension | Point-to-Point Solution | LoRaWAN Network |
| Architectural Complexity | No gateway needed, direct communication | Requires gateway + network server |
| Applicable Scale | Up to 10 nodes | Thousands of nodes access |
| Real-time Performance | Millisecond latency | Affected by scheduling (second-level) |
| Sicherheit | Relies on custom encryption (e.g., AES-128) | Supports end-to-end encryption + two-way authentication |
| Cost | Hardware cost reduced by 30% | Requires payment for network service |
Deployment Practice Example
In the renovation of a wind turbine vibration monitoring system in a wind farm, engineers deployed LoRa point-to-point links between the 80-meter-high nacelle and the ground maintenance station:
Hardware selection: IP67 protection grade LoRa module, operating temperature -40℃~85℃
Parameter configuration: SF=10, BW=250kHz, transmit power 20dBm
Data encapsulation: vibration spectrum data is compressed into a 16-byte load, 1 frame per second transmission
Measured results: in a strong electromagnetic interference environment, packet loss rate <0.1%, alternative to the original fiber optic solution to save 75% of the cabling costs
The value of this solution lies in the lightweight communication architecture to solve the special data transmission needs of the local area. It not only avoids the investment of complex network deployment, but also maintains LoRa’s unique penetration capability and low power consumption advantages. For small and medium scale, directional transmission demand scenarios, point-to-point mode is still the most cost-effective solution.
