1. Introduction
You may ask yourself if you should go with multiple ESP32 modules around your house or if a central one is more suitable/enough, or can a single BLE gateway be able to receive data from outdoor sensors?
So as to give you an idea about the Theengs Bridge capabilities versus a regular ESP32 module we have setup a house with sensors at different distances and location to represent some use cases:
- Measuring the temperature inside a fridge and freezer,
- Measuring the temperature outside on the porch,
- Having a sensor in a shed or another building outside of the house,
- Having a sensor at a mailbox location,
- Having a sensor outdoor.
These different use cases represents questions we receive from our customers.
Our setup represents a typical suburban home with various IoT devices spread across the property, challenging the range and reliability of the gateways.
2. Test Setup and Methodology
2.1 Environment Layout
Our test environment is structured as follows:
- Point G: Gateways location inside the house, height 31in/0.8m
- Point A: Outdoor, ~85ft/26m from the gateway, height 3.3ft/1m
- Point B: In a detached shed, ~50ft/15m from the house, height 3.6ft/1.1m
- Point C: Furthest outdoor at the mailbox, ~100ft/30.5m from the gateway, height 3.3ft/1m
- Point D: Below the porch, ~25ft/7.6m from the gateway, height 9ft/2.7m
- Points E and F: Inside the freezer and fridge, ~15ft/4.5m from the gateway
This layout provides a mix of indoor and outdoor locations, varying distances, and potential obstacles (walls, doors, outdoor elements) to test signal penetration and range.
2.2 Equipment Used
- Theengs Bridge with ESP32 WROOVER, external antenna, using WiFi connection
- Standard ESP32 WROOM module, embedded antenna
- Sensor Easy commercial BLE sensors set to 4dBm tx power, 3s interval, located at points A through F
- Firmware OpenMQTTGateway sha: 258e3b
- Configuration (scanduration: 10000, interval:100, minrssi: -120, onlysensors: true)
- InfluxDB for data storage
- Grafana for data visualization
2.3 Testing Protocol
The testing was done during a 24h windows, and we measured:
- Signal Strength:
- Measure RSSI (Received Signal Strength Indicator) values for sensors with both gateway devices.
- Record measurements at different times of day to account for potential interference variations.
- Data Throughput:
- Monitor the rate of successful data transmissions from each sensor to the gateway.
- Range and Reliability Test:
- Focus on the furthest points (A, B, and C) to assess the maximum effective range.
3. Result
1. Signal strength
We see a noticeable 4.2dB difference, meaning that the Theengs Bridge should have a longer effective range and better signal reception through obstacles.
2. Successfull data transmission caught by each gateway
The Theengs bridge was able to receive 2 times more points compared to the ESP32 module.
Let's finish by the questions everyone has in mind, what about the range.
3. Range and reliability testing
Here are the number of measurements following the sensor distance:
We can see that the Theengs Bridge consistently outperform the ESP32 module, especially when the range goes more than 15 meters (~50ft).
In details:
If we come back to our use cases we can deduct the following results:
| Use case | Distance between sensor and gateways | ESP32 Module | Theengs Bridge |
| Points E and F: Inside the freezer and fridge | ~15ft/4.5m | Good | Excellent |
| Point D: Below the porch | ~25ft/7.6m | Good | Good |
| Point B: In a detached shed | ~50ft/15m | Fair | Good |
| Point A: Outdoor | ~85ft/26m | Poor | Good |
| Point C: Furthest outdoor at the mailbox | ~100ft/30.5m | Poor | Poor |
We see here that the Theengs Bridge brings a real benefits for range and capacity to retrieve BLE advertisements compared to an ESP32 module with embedded antenna making it an interesting choice as a central BLE gateway.
Limitations of the study:
- Limited Duration: 24-hour test period may not capture long-term performance variations.
- Single Location: Results may not represent all home layouts or construction types.
- Environmental Factors: Weather conditions and other 2.4 GHz interference sources were not controlled or reported.
- Sample Size: Only one unit of each gateway was tested, not accounting for unit-to-unit variations.
Future testing:
- Compare the number of points/packets received versus the number emitted by the sensors