Field Guide · hardware

Also known as: LimeSDR, LimeSDR Mini

LimeSDR is an open-source, full-duplex transmit-and-receive software-defined radio built around Lime Microsystems’ LMS7002M field-programmable RF transceiver, covering 100 kHz to 3.8 GHz with 12-bit ADC sampling.1 Unlike a receive-only dongle, it can transmit and receive at the same time and offers two independent channels, making it a MIMO-capable platform.2

02 GHz4 GHz6 GHz LimeSDR (100 kHz–3.8 GHz) TX + RX, 2×2 MIMO
LimeSDR transmits and receives full-duplex across HF through low-microwave, with two channels for MIMO.

Overview

The LimeSDR targets developers building and testing wireless systems rather than pure listeners: cellular (GSM, LTE), IoT radios, and general RF prototyping. Its wide instantaneous bandwidth — up to about 61.44 MHz on the full-size board — and two-channel front end let it host software base stations and duplex links that a receive-only SDR cannot. The heart of the board is the LMS7002M, a highly configurable zero-IF transceiver whose gain, filtering, and mixing are all set in software, with an on-board FPGA handling sample transport over USB 3.0.

What it is

Each of the LMS7002M’s two RX and two TX chains has its own tuner, so the board can run 2×2 MIMO or act as two loosely related radios. Samples move as IQ over USB 3.0; the FPGA does packing and buffering while demodulation and decoding stay on the host. Software support centres on Lime’s LimeSuite driver and a SoapySDR module (SoapyLMS7), which plugs the board into GNU Radio, SDRangel, and the wider Soapy ecosystem. Because transmit is a first-class function, LimeSDR is subject to the same regulatory care as any transmitter — it can radiate, and licensing rules apply.

Variants

The line spans several form factors around the same silicon:

  • LimeSDR (USB) — the original full-size board: two RX and two TX channels, ~61.44 MHz bandwidth, USB 3.0.
  • LimeSDR Mini / Mini 2.0 — a smaller, lower-cost single-channel version with reduced bandwidth, the most common entry point.
  • LimeSDR-PCIe and LimeNET / LimeSDR-QPCIe — PCIe and appliance variants aimed at fixed infrastructure and multi-radio deployments.

All share the LMS7002M transceiver family and the LimeSuite/SoapySDR software stack, so code and flowgraphs port across them.

Relevance to SDR

LimeSDR is a workhorse for two-way and lab work: running an experimental cellular cell, prototyping a protocol end-to-end, or testing a receiver against a signal you generate yourself. It overlaps the HackRF in the “wide-range transceiver” niche but adds full-duplex operation, a second channel, and 12-bit sampling.

For trunking reception it is capable but not the natural pick — transmit and MIMO are irrelevant to receive-only scanning, and its dynamic range in a single RX channel is comparable to other 12-bit SDRs rather than exceptional. GopherTrunk provides native USB backends for RTL-SDR, HackRF, and Airspy, not for the LimeSuite stack, so any LimeSDR use would go through a SoapySDR bridge; treat it as a general-purpose transceiver whose scanning role is secondary to its development strengths.

Sources

  1. LimeSDR — Wikipedia, on the LimeSDR platform, the LMS7002M transceiver, and its full-duplex MIMO capabilities. 

  2. LimeSDR — Lime Microsystems / Myriad-RF, official project site with tuning range, channel count, bandwidth, and software details. 

See also