USRP B2xx Series: USB Software Defined Radio Devices

The USRP B2xx Series is the entry-level USRP product line, delivering a full 70 MHz – 6 GHz software defined radio experience over a single USB 3.0 cable. All B Series radios are bus-powered (with a few exceptions noted below), making them the most portable USRPs available. They share a common integrated RF frontend based on the Analog Devices AD936x transceiver family and are supported by UHD 3.8.4 and later.

Supported Models

B200

Single TX/RX channel. Internal GPSDO option available. USB Type-B connector.

B210

Two TX/RX channels (2×2 MIMO). MICTOR debug connector. Internal GPSDO option. USB Type-B connector.

B200mini

Compact single-channel version. USB Micro-B SuperSpeed connector.

B205mini

Compact single-channel version with additional industrial-temperature range. USB Micro-B SuperSpeed connector.

B206mini

Latest compact variant. USB Type-C locking connector. Requires UHD 4.9 or above.

Features

Hardware Capabilities

Frequency range: 70 MHz – 6 GHz (integrated RF frontend)
LO tuning range: 50 MHz – 6 GHz
Analog bandwidth: 200 kHz – 56 MHz (seamlessly adjustable)
Connection: USB 3.0 (also works on USB 2.0 with reduced throughput)
External PPS reference input
External 10 MHz reference input
Configurable master clock rate (5 MHz – 61.44 MHz single-channel; up to 30.72 MHz dual-channel)
GPIO header
JTAG connector (B200mini, B205mini, B206mini; not present on B200)
Internal GPSDO option (B200 and B210 only)
MICTOR debug connector (B210 only)

FPGA Capabilities

Timed commands in FPGA
Timed sampling in FPGA

RF Frontend Gains

RX gain range: 76 dB
TX gain range: 89.8 dB

When a GPSDO module is installed (B200/B210 only) or when using USB 2.0, an external DC power supply or a dual-port USB power cable must be used to supplement bus power.

Getting Started

Kit Contents

Every B Series kit includes:

USRP B200 / B210 / B200mini / B205mini / B206mini
USB 3.0 cable (connector type varies by model—see below)
Universal power supply (B210 only)

Verify all kit contents immediately upon receipt. If any items are missing, contact your sales agent or Ettus Research Technical Support.

USB Connector Reference

Model	Device-side USB Connector
B200 / B210	USB Type-B
B200mini / B205mini	USB Micro-B SuperSpeed
B206mini	USB Type-C (locking screw variant)

Install UHD

Download and install UHD on your host computer before connecting the device:

B200, B210, B200mini, B205mini: UHD 3.8.4 or above
B206mini: UHD 4.9 or above

It is generally recommended to use the latest UHD version. See Installing UHD from Binaries or Building UHD from Source.

Connect the Device

Plug the included USB 3.0 cable into an available USB 3.0 Type-A port on your host computer. The B Series draws power directly from the USB bus; no additional power connection is needed for most variants. Once connected, verify operation by running:

uhd_find_devices
uhd_usrp_probe

Connecting in UHD

C++ Example

#include <uhd/usrp/multi_usrp.hpp>
#include <iostream>

int main() {
    // Connect to any detected B200-series device
    auto usrp = uhd::usrp::multi_usrp::make("type=b200");

    // Set center frequency to 915 MHz
    usrp->set_rx_freq(915e6);

    // Set sample rate to 1 MS/s
    usrp->set_rx_rate(1e6);

    // Set gain
    usrp->set_rx_gain(30.0);

    std::cout << "RX frequency: " << usrp->get_rx_freq() << " Hz\n";
    std::cout << "RX rate:      " << usrp->get_rx_rate() << " S/s\n";
    return 0;
}

Python Example

import uhd

# Connect to any detected B200-series device
usrp = uhd.usrp.MultiUSRP("type=b200")

# Set center frequency
usrp.set_rx_freq(915e6)

# Set sample rate
usrp.set_rx_rate(1e6)

# Set gain
usrp.set_rx_gain(30.0)

print(f"RX frequency: {usrp.get_rx_freq():.0f} Hz")
print(f"RX rate:      {usrp.get_rx_rate():.0f} S/s")

Master Clock Rate

The master clock rate feeds the RF frontends and DSP chains. It can be set between 5 MHz and 61.44 MHz (single-channel) or up to 30.72 MHz in dual-channel mode. Rates above 56 MHz are possible but not recommended.

Setting the Clock Rate

# Via command-line argument
uhd_usrp_probe --args="master_clock_rate=52e6"

import uhd

usrp = uhd.usrp.MultiUSRP("type=b200")

# Explicit clock rate (locks auto-selection)
usrp.set_master_clock_rate(16e6)

# Or use the property tree directly
usrp.get_tree().access_double('/mboards/0/tick_rate').set(16e6)

Automatic Clock Rate Selection

By default, UHD automatically chooses the largest valid master clock rate for the requested sample rate, maximizing the number of half-band filter stages available. Manual selection can be re-enabled after automatic mode:

import uhd

usrp = uhd.usrp.MultiUSRP("type=b200")

# Check auto mode status
print(usrp.get_tree().access_bool('/mboards/0/auto_tick_rate').get())  # True

# Lock to explicit rate (disables auto)
usrp.set_master_clock_rate(16e6)

# Re-enable auto
usrp.get_tree().access_bool('/mboards/0/auto_tick_rate').set(True)
usrp.set_rx_rate(7e6)  # UHD now picks an appropriate MCR automatically
print(usrp.get_master_clock_rate())  # e.g., 56000000.0

Changing the master clock rate reconfigures the entire clocking chain and invalidates any previous time synchronization. When synchronizing multiple B200 units, always specify a master_clock_rate explicitly rather than relying on auto selection.

Key Device Arguments

Argument	Description	Example
`type`	Select B200 family	`type=b200`
`master_clock_rate`	Set master clock at init	`master_clock_rate=52e6`
`fpga`	Override FPGA image path	`fpga=usrp_b200_fpga.bin`
`fw`	Override firmware image path	`fw=usrp_b200_fw.hex`
`recv_frame_size`	Tune USB transfer frame size	`recv_frame_size=1024`
`enable_user_regs`	Enable access to custom FPGA user registers	`enable_user_regs`

Custom FPGA Images

The B Series FPGA source is open and can be modified and rebuilt for custom DSP pipelines. To control user-defined IP via UHD, set USER_SETTINGS=1 in b200_core.v (for B200/B210) or b205_core.v (for mini variants), then use the enable_user_regs device argument:

auto usrp = uhd::usrp::multi_usrp::make("type=b200,enable_user_regs");
auto user_regs = usrp->get_user_settings_iface();
user_regs->poke32(addr, data);

Front Panel LEDs

B200 / B210
B200mini / B205mini / B206mini

LED ID	Description	States
LED600	Power indicator	Off / Blue (USB power) / Red (external power)
LED800	Channel 2 RX2 activity	Off / Green (receiving)
LED801	Channel 2 TX/RX activity	Off / Green (RX) / Red (TX) / Orange (switching)
LED802	Channel 1 TX/RX activity	Off / Green (RX) / Red (TX) / Orange (switching)
LED803	Channel 1 RX2 activity	Off / Green (receiving)
LED100	GPS lock indicator	Off (no lock) / Green (locked)

LED ID	Description	States
PWR LED	Power indicator	Off (no power) / On (power applied)
TRX LED	TX/RX activity	Off / Green (RX) / Red (TX) / Orange (switching)
RX2 LED	RX2 activity	Off / Green (receiving)
S0 LED	Reference lock	Off / Green (locked)
S1 LED	Reference present	Off / Green (reference level high)

Care and Handling

Observe these precautions to avoid damage:

Never apply more than -15 dBm of power into any RF input.
Always use at least 30 dB attenuation when operating in a loopback configuration.
Never allow metal objects to touch the circuit board while powered.
Always terminate the TX port with an antenna or a 50 Ω load.

Known Issues

When synchronizing multiple B Series devices in time, always specify an explicit master_clock_rate instead of relying on automatic selection.
The B200 and B210 cannot use an external 10 MHz reference if a GPSDO is installed. Remove the GPSDO physically before using an external reference.
If streaming stability issues occur, try setting recv_frame_size=1024 in the device args.

Introduction

Installation

USRP Devices

Supported Models

B200

B210

B200mini

B205mini

B206mini

Features

Hardware Capabilities

FPGA Capabilities

RF Frontend Gains

Getting Started

Kit Contents

USB Connector Reference

Install UHD

Connect the Device

Connecting in UHD

C++ Example

Python Example

Master Clock Rate

Setting the Clock Rate

Automatic Clock Rate Selection

Key Device Arguments

Custom FPGA Images

Front Panel LEDs

Care and Handling

Known Issues

Additional Resources

Build docs developers (and LLMs) love

Introduction

Installation

USRP Devices

Documentation Index

​Supported Models

B200

B210

B200mini

B205mini

B206mini

​Features

​Hardware Capabilities

​FPGA Capabilities

​RF Frontend Gains

​Getting Started

​Kit Contents

​USB Connector Reference

​Install UHD

​Connect the Device

​Connecting in UHD

​C++ Example

​Python Example

​Master Clock Rate

​Setting the Clock Rate

​Automatic Clock Rate Selection

​Key Device Arguments

​Custom FPGA Images

​Front Panel LEDs

​Care and Handling

​Known Issues

​Additional Resources

Build docs developers (and LLMs) love

Supported Models

Features

Hardware Capabilities

FPGA Capabilities

RF Frontend Gains

Getting Started

Kit Contents

USB Connector Reference

Install UHD

Connect the Device

Connecting in UHD

C++ Example

Python Example

Master Clock Rate

Setting the Clock Rate

Automatic Clock Rate Selection

Key Device Arguments

Custom FPGA Images

Front Panel LEDs

Care and Handling

Known Issues

Additional Resources