WiFi connection worst than ESP8266

[ClaudeSimard]

Hi,

Recently we have migrated a project from ESP8266 to ESP32 but we are facing issues with WiFi signal quality.

ESP32 design is based on :
ESP32-DevKitC V4 using ESP32-WROOM-32UE (IPEX) version
Arduino IDE using core 1.0.6

The ESP's runs a simple passthrough serial link to a CortexM7 CPU for modbus TCPip transaction.
The electronic module is installed in a aluminium pot room environment (high temp, high magnetics fields and module mount on a metal structure)
We connect to and Cisco AP infrastructure with a fixed IP adress. Many APs are available , with the same SSID and pswd. Code is looking for the best one and connect to it.

The code on design GEN0 (using ESP8266) is working fine with very good transaction quality in the plant environment installation (99.95% success)

The new design GEN1 with ESP32 (Espressif is installed at the same location than GEN0 module.

With GEN1 design the success rate on transaction is degraded (< 75%) and very often we lose connection for 3-4 minutes without proper reconnection.

In the code we tested :

1) Disable power saving mode (esp_wifi_set_ps (WIFI_PS_NONE));
2) Force connection in 802.11B protocol to be more robust (esp_wifi_set_protocol(WIFI_IF_STA, WIFI_PROTOCOL_11B));
3) Change CPU speed from 240 MHZ to 160 MHZ and than to 80 MHZ (worst results);
4) Use max power setting on transmission (esp_wifi_set_max_tx_power(WIFI_POWER_19_5dBm));
5) Make sure than country setting are set properly (default CN);

When we look at RSSI level on connection, it's pretty good < -50dBm, better than RSSI number obtain with ESP8266 card.

It's like if the ESP32 is very sensible to SNR (signal to noise ratio) or WiFi signal reflection
Until now we have four GEN1 modules running in field with about the same results (50-75% success), always worst than GEN0 module based on ESP8266 (38 units with 99.95% success).

Any idea what could explain the bad results obtained with ESP32 ?(on paper ESP32 has better specifications than ESP8266)

All help and guidance appreciated.

Best regards

[ESP_Minatel]

Hi,

Can you share your antenna specs? Are you sure that your antenna is for 2.4GHz?

[ClaudeSimard]

Hi

Antenna specification : https://www.digikey.ca/en/products/deta ... M/5962661

We are using same antenna on ESP32 and ESP8266 systems.

Best regards