Choosing a cellular module as 2G and 3G shrink in India

Many older field devices use a 2G modem, because 2G was cheap and its coverage reached almost everywhere. A new design should not start there. Operators in many countries have switched off 2G and 3G, and Indian networks are moving the same way. A product meant to run for ten years needs a module on a network that will still be there.

The realistic options

LTE Cat-1 and Cat-1 bis. This is the default for most Indian IoT devices today. It runs on the ordinary 4G network and uses the same bands as phones, so coverage matches what you get on a handset. Typical Cat-1 speeds are up to 10 Mbit/s down and 5 Mbit/s up, enough for telemetry, OTA updates and small images. Modules often fall back to 2G or 3G on some variants, but we do not design around that. Cat-1 bis needs one antenna, which simplifies layout. Our note on BLE, Wi-Fi, LoRa and LTE Cat-1 compares it with the alternatives.

LTE Cat-M and NB-IoT. These are built for low power and small data. They suit battery devices that send a few hundred bytes a day, and they extend deep coverage. The caveat is availability: support depends on the operator, the circle and the roaming and SIM profile, and it has changed over time. Do not assume a module that supports NB-IoT will find a network to use it.

What to settle before choosing

• Bands: the module must cover the bands your target operator uses in India. Commonly cited LTE bands include B3, B5, B8, B1, B40 and B41, but the list varies by operator and circle.
• SIM type: a plain consumer SIM, an M2M SIM, or eSIM. Provisioning and roaming terms differ.
• Operator support: ask each operator in writing about Cat-1, Cat-M and NB-IoT support, IoT plans, and the sunset plan for 2G and 3G.
• Firmware: AT command set, power-saving features such as PSM and eDRX, and how long the vendor supports the module.

Certification

A module vendor’s certificates do not transfer to your finished product. A product may need its own approvals, which can include WPC and TEC procedures and BIS safety registration, plus operator acceptance. These rules change, so verify them with an accredited test lab or the official portals before you freeze a design. Pre-certified modules reduce the radio testing effort, but not to zero.

Last checked: November 2026.

What this does not settle

Choosing a module does not guarantee coverage at your site. Test a device at the actual location, on the intended operator, before you commit.

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If you are choosing a modem for a new Indian product, book a discovery call and read about our embedded firmware and PCB design work.