LimeSDR Mini Configuration Guide

📋 LimeSDR Mini Overview

🔧 Technical Specifications

Frequency Range: 10MHz - 3.8GHz
Bandwidth: 30.72MHz instantaneous
Interface: USB 3.0 Type-A
Power: USB powered (5V/1.5A)
Size: 69mm x 31.4mm x 8mm
Weight: 20g
Duplex: Full-duplex (simultaneous TX/RX)

⭐ Key Features

2x2 MIMO: Support for MIMO applications
Open Source: Full open-source software stack
Compact: Ultra-portable form factor
Wide Coverage: 10MHz to 3.8GHz frequency range
Full Duplex: Simultaneous transmit and receive
FPGA: Intel Altera MAX 10 for processing
Community: Strong open-source community

🎯 Use Cases

IoT Security Testing: NB-IoT, LTE-M testing
GSM Research: 900MHz, 1800MHz operations
Software Radio: GNU Radio applications
Education: RF and communications learning
Prototyping: Wireless system development
Spectrum Analysis: RF signal monitoring
Research Projects: Academic and commercial R&D

⚠️ Important Prerequisites

Before starting: Ensure you have a Raspberry Pi 4 with Ubuntu 22.04 LTS installed. This guide assumes you have basic Linux command line knowledge and understanding of SDR concepts.

🔧 Installation & Driver Setup

Install System Dependencies

                            # Update system packages
sudo apt update && sudo apt upgrade -y

# Install build dependencies
sudo apt install -y git cmake build-essential libsqlite3-dev
sudo apt install -y libusb-1.0-0-dev pkg-config

# Install additional libraries
sudo apt install -y libwxgtk3.0-gtk3-dev freeglut3-dev
                        

Install SoapySDR Framework

                            # Install SoapySDR and tools
sudo apt install -y soapysdr-tools soapysdr-module-all
sudo apt install -y python3-soapysdr

# Verify SoapySDR installation
SoapySDRUtil --info
                        

Build and Install LimeSuite

                            # Clone LimeSuite repository
git clone https://github.com/myriadrf/LimeSuite.git
cd LimeSuite
git checkout stable

# Create build directory
mkdir builddir && cd builddir

# Configure build (disable GUI components for headless setup)
cmake ../ \
    -DENABLE_QUICKTEST=ON \
    -DENABLE_GUI=OFF \
    -DENABLE_DESKTOP=OFF

# Build LimeSuite
make -j$(nproc)

# Install LimeSuite
sudo make install
sudo ldconfig
                        

Configure udev Rules

                            # Create udev rules for LimeSDR Mini
sudo tee /etc/udev/rules.d/64-limesuite.rules << 'EOF'
# LimeSDR Mini
SUBSYSTEM=="usb", ATTRS{idVendor}=="1d50", ATTRS{idProduct}=="6108", MODE="666", GROUP="plugdev"
SUBSYSTEM=="usb", ATTRS{idVendor}=="0403", ATTRS{idProduct}=="601f", MODE="666", GROUP="plugdev"

# LimeSDR USB 
SUBSYSTEM=="usb", ATTRS{idVendor}=="1d50", ATTRS{idProduct}=="6109", MODE="666", GROUP="plugdev"

# Performance optimizations
SUBSYSTEM=="usb", ATTRS{idVendor}=="1d50", ATTRS{idProduct}=="6108", RUN+="/bin/sh -c 'echo 128 > /sys$devpath/../../../power/autosuspend_delay_ms'"
EOF

# Reload udev rules
sudo udevadm control --reload-rules
sudo udevadm trigger

# Add user to plugdev group
sudo usermod -a -G plugdev $USER
                        

✅ Reboot Required

After completing the installation, reboot your system to ensure all changes take effect:

sudo reboot

⚙️ YateBTS Configuration

Verify LimeSDR Mini Detection

                            # Check USB device enumeration
lsusb | grep -E "(1d50:6108|0403:601f)"

# Test LimeSDR Mini with utilities
LimeUtil --find
LimeUtil --make=LimeSDR-Mini --info

# Verify SoapySDR detection
SoapySDRUtil --probe="driver=lime"
                        

Configure YateBTS for LimeSDR Mini

                            # Create YateBTS configuration backup
sudo cp /etc/yate/ybts.conf /etc/yate/ybts.conf.backup

# Edit YateBTS configuration
sudo nano /etc/yate/ybts.conf
                        

YateBTS Configuration for LimeSDR Mini:

                            [transceiver]
# Use SoapySDR interface for LimeSDR Mini
radiodevice=soapy
radio_args=driver=lime,soapy=0

# Transceiver settings
tx_attenuation=0
rx_gain=40
clockref=internal

[soapy]
# LimeSDR Mini specific settings
device_args=driver=lime

# Sample rate (critical for GSM compatibility)
sample_rate=13000000

# Bandwidth settings
bandwidth=10000000

# Gain settings (adjust based on your setup)
rx_gain=30
tx_gain=30

# Channel configuration
channels=1
antenna=LNAW

# Clock reference
clock_ref=internal
                        

Configure GSM Parameters

                            # GSM frequency configuration
[gsm]
# GSM 900 example - adjust for your region
Radio.C0=975                    # ARFCN for GSM 900
Radio.Band=900                  # GSM band
Radio.PowerManager.MaxAttenDB=10  # Maximum attenuation

# Network configuration
GSM.Identity.MCC=901           # Mobile Country Code (test network)
GSM.Identity.MNC=70            # Mobile Network Code (test network)
GSM.Identity.LAC=1000          # Location Area Code
GSM.Identity.CI=10             # Cell Identity

# Power and timing
GSM.Radio.RxGain=47            # Receive gain
GSM.Radio.TxAttenOffset=0      # Transmit attenuation offset
                        

Test Configuration

                            # Test YateBTS configuration
sudo yatebts -c /etc/yate/ybts.conf --validate

# Start YateBTS service
sudo systemctl restart yatebts
sudo systemctl status yatebts

# Check logs for any issues
sudo journalctl -u yatebts -f
                        

🚀 Performance Optimization

📡 RF Optimization

Antenna Connection: Use quality uFL to SMA adapters
Impedance Matching: Ensure 50Ω throughout RF path
VSWR: Keep below 2:1 for optimal performance
Cable Length: Minimize coaxial cable length
Isolation: Ensure adequate TX/RX isolation
Filtering: Use appropriate band-pass filters

💻 System Optimization

USB Performance: Use USB 3.0 ports only
Power Management: Disable USB autosuspend
CPU Governor: Set to performance mode
Memory: Ensure adequate free RAM
Interrupts: Check for USB interrupt conflicts
Kernel: Use recent kernel versions

⚙️ LimeSDR Mini Settings

Sample Rate: Use 13MHz or 26MHz for GSM
Gain Control: Start conservative, adjust gradually
Calibration: Allow 5-10 minute warm-up
Temperature: Monitor device temperature
Buffering: Optimize buffer sizes
Threading: Adjust thread priorities

Apply System Optimizations

                            # Set CPU governor to performance
echo performance | sudo tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor

# Disable USB autosuspend for LimeSDR Mini
echo 'SUBSYSTEM=="usb", ATTRS{idVendor}=="1d50", ATTRS{idProduct}=="6108", ATTR{power/autosuspend}="-1"' | sudo tee -a /etc/udev/rules.d/64-limesuite.rules

# Increase USB buffer sizes
echo 'vm.dirty_ratio = 15' | sudo tee -a /etc/sysctl.conf
echo 'vm.dirty_background_ratio = 5' | sudo tee -a /etc/sysctl.conf

# Apply changes
sudo sysctl -p
                        

Optimize LimeSDR Mini Parameters

                            # Test different sample rates
for rate in 13000000 26000000; do
    echo "Testing sample rate: $rate"
    SoapySDRUtil --probe="driver=lime,soapy=0" --rate=$rate
done

# Check calibration status
LimeUtil --make=LimeSDR-Mini --info | grep -i cal

# Run performance test
LimeUtil --make=LimeSDR-Mini --test
                        

🧪 Testing & Validation

Test	Command	Expected Result	Action if Failed
Device Detection	`LimeUtil --find`	Device found and listed	Check USB connection, drivers
SoapySDR Detection	`SoapySDRUtil --probe="driver=lime"`	LimeSDR device detected	Reinstall SoapySDR modules
Device Info	`LimeUtil --make=LimeSDR-Mini --info`	Firmware version, serial number	Update firmware if needed
Self Test	`LimeUtil --make=LimeSDR-Mini --test`	All tests pass	Check hardware, calibration
YateBTS Config	`sudo yatebts --validate`	Configuration valid	Fix configuration errors

Run Comprehensive Test Suite

                            #!/bin/bash
# LimeSDR Mini Test Script

echo "=== LimeSDR Mini Test Suite ==="

# Test 1: Device Detection
echo "1. Testing device detection..."
if LimeUtil --find | grep -q "LimeSDR Mini"; then
    echo "✅ Device detected"
else
    echo "❌ Device not found"
    exit 1
fi

# Test 2: SoapySDR Interface
echo "2. Testing SoapySDR interface..."
if SoapySDRUtil --probe="driver=lime" | grep -q "Found"; then
    echo "✅ SoapySDR interface working"
else
    echo "❌ SoapySDR interface failed"
    exit 1
fi

# Test 3: Device Information
echo "3. Checking device information..."
LimeUtil --make=LimeSDR-Mini --info

# Test 4: Self Test
echo "4. Running device self test..."
if LimeUtil --make=LimeSDR-Mini --test; then
    echo "✅ Self test passed"
else
    echo "❌ Self test failed"
fi

# Test 5: YateBTS Configuration
echo "5. Validating YateBTS configuration..."
if sudo yatebts -c /etc/yate/ybts.conf --validate; then
    echo "✅ Configuration valid"
else
    echo "❌ Configuration invalid"
fi

echo "=== Test Suite Complete ==="
                        

🔧 Troubleshooting Guide

❌ Device Not Detected

Check USB 3.0 connection
Verify sufficient power (1.5A)
Try different USB port
Check udev rules
Reinstall drivers

📊 Poor Performance

Check sample rate settings
Optimize gain settings
Verify antenna connection
Monitor USB bandwidth
Check for interference

⚡ Calibration Issues

Allow adequate warm-up time
Run manual calibration
Check temperature stability
Verify impedance matching
Test with dummy load

🚨 Common Error Solutions

"Device not found": Check USB connection and drivers
"Permission denied": Verify user in plugdev group
"Sample rate error": Use 13MHz or 26MHz for GSM
"Calibration failed": Check antenna connection and warm-up
"High error rate": Optimize gain settings and RF path

📶 LimeSDR Mini Configuration Guide