N320/N321
Contents
- 1 Device Overview
- 2 Key Features
- 3 RF Specifications
- 4 Power
- 5 Hardware Specifications
- 6 Physical Specifications
- 7 Environmental Specifications
- 8 Schematics
- 9 GPSDO
- 10 FPGA
- 11 Interfaces and Connectivity
- 12 Certifications
- 13 Certificate of Volatility
- 14 Downloads
- 15 Choosing a Host Interface
- 16 International Power Supply Options
- 17 Option: USRP N320/N321 Rackmount
- 18 Guidance on SFP+ Adapters for Fiber Connectivity on USRP N320/N321
- 19 Guidance on 10Gb SFP+ to RJ45 Adapters
Device Overview
The USRP N320 is a networked software defined radio that provides reliability and fault-tolerance for deployment in large scale and distributed wireless systems. This is a high performance SDR that uses a unique RF design by Ettus Research to provide 2 RX and 2 TX channels in a half-wide RU form factor. Each channel provides up to 200 MHz of instantaneous bandwidth, and covers a frequency range from 3 MHz to 6 GHz. The baseband processor uses the Xilinx Zynq-7100 SoC to deliver a large user programmable FPGA for real-time, low latency processing and a dual-core ARM CPU for stand-alone operation.Support for 1 GbE, 10 GbE, and Aurora interfaces over two SFP+ ports and 1 QSFP+ port enables high throughput IQ streaming to a host PC or FPGA coprocessor. A flexible synchronization architecture with support for LO sharing for TX and RX, 10 MHz clock reference, PPS time reference, GPSDO, and White Rabbit enables implementation of phase coherent MIMO testbeds. The USRP N320 leverages recent software developments in UHD to simplify control and management of multiple devices over the network with the unique capability to remotely administrate tasks such as debugging, updating software, rebooting, resetting to factory state, and monitoring system health.
Key Features
N320
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N321
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RF Specifications
Transmitter
- Number of channels: 2
- Frequency Range: 3 MHz to 6 GHz
- Maximum instantaneous bandwidth: 200 MHz
- Maximum output power (P out ): See Table 1
- Gain range
- 0 dB to 60 dB (1 MHz to 6 GHz)
- Gain step: 1 dB
- Supported I/Q sample rates:
- 200 MHz, 245.76 MHz, 250 MHz
- Output third-order intercept (OIP3) See Table 2
- Tuning Time: 245 us
- TX/RX Switching Time: 750 ns
- Filter Banks
- 450 – 650 MHz
- 650 – 1000 MHz
- 1000 – 1350 MHz
- 1350 – 1900 MHz
- 1900 – 3000 MHz
- 3000 – 4100 MHz
- 4100 – 6000 MHz
- External LO Frequency Range: 450 MHz - 6.0 GHz
| Frequency | Maximum Output Power |
|---|---|
| 3 MHz - 450 MHz | +10 dBm |
| 450 MHz - 1000 MHz | +20 dBm |
| 1 GHz - 4.25 GHz | +18 dBm |
| 4.25 GHz - 6 GHz | +15 dBm |
Table 1: Maximum Output Power
| Frequency | Output Third-Order Intercept (OIP3) |
|---|---|
| 3 MHz - 450 MHz | > 15 dBm |
| 450 MHz - 1.6 GHz | > 28 dBm |
| 1.6 GHz - 5.8 GHz | > 25 dBm |
| 5.8 GHz - 6.0 GHz | > 23 dBm |
Table 2: Output Third-Order Intercept (OIP3)
| Frequency Offset | 1.0 GHz | 2.0 GHz | 3.0 GHz | 5.5 GHz |
|---|---|---|---|---|
| 10 kHz | -117 | -110 | -108 | -103 |
| 100 kHz | -117 | -110 | -108 | -104 |
| 1 MHz | -145 | -137 | -135 | -130 |
Table 3: TX Phase Noise (dBc/Hz)
Receiver
- Number of channels: 2
- Frequency Range: 3 MHz to 6 GHz
- Maximum instantaneous bandwidth: 200 MHz
- Gain range
- 0 dB to 60 dB (1 MHz to 6 GHz)
- Gain step: 1 dB
- Maximum recommended input power (P in ) 1 dB: -15 dBm
- Noise figure: See Table 3
- Third-order intermodulation distortion (IMD3) See Table 4
- Supported I/Q sample rates
- 200 MHz, 245.76 MHz, 250 MHz
- Tuning Time: 245 us
- TX/RX Switching Time: 750 ns
- Filter Banks
- 450 – 760 MHz
- 760 – 1100 MHz
- 1100 – 1410 MHz
- 1410 – 2050 MHz
- 2050– 3000 MHz
- 3000 – 4500 MHz
- 4500 – 6000 MHz
- External LO Frequency Range: 450 MHz - 6.0 GHz
| Frequency | TX/RX Port Noise Figure | RX2 Port Noise Figure |
|---|---|---|
| < 800 MHz | 11.0 dB | 10.0 dB |
| 800 MHz - 1.8 GHz | 6.5 dB | 5.5 dB |
| 1.8 GHz - 2.8 GHz | 7.0 dB | 6.0 dB |
| 2.8 GHz - 3.8 GHz | 7.5 dB | 6.5 dB |
| 3.8 GHz - 5.0 GHz | 8.5 dB | 7.5 dB |
| 5.0 GHz - 6.0 GHz | 11.0 dB | 10.0 dB |
Table 3: RX Noise Figure
| Frequency | RX Input Third-Order Intercept (IIP3) (dBm) |
|---|---|
| 450 MHz - 1.0 GHz | > 13 dBm |
| 1.0 GHz - 4.5 GHz | > 17 dBm |
| 4.5 GHz - 6.0 GHz | > 16 dBm |
Table 4: RX Input Third-Order Intercept (IIP3) (dBm)
Onboard DRAM
- DDR3 Memory size
- 2,048 MB (PL)
- 1,024 MB (PS)
Power
You must use either the Level VI Efficiency power supply provided in the shipping kit, or another UL listed ITE power supply marked LPS, with the USRP N320/N321.
- Input voltage: 12 VDC
- Input current: 7.0 A, maximum
- Typical power consumption: 60 W to 75 W, varies by application
Hardware Specifications
- Ettus Research recommends to always use the latest stable version of UHD
- If you need to clean the module, wipe it with a dry towel.
N320
- Current Hardware Revision: A
- Minimum version of UHD required: 3.14.0.0
- Due to product compliance restrictions on products with TPM (Trusted Platform Module) components to a few countries, the USRP N320/N321 is available in two variants:
- Standard variant with TPM
- Non-TPM variant
N321
- Current Hardware Revision: A
- Minimum version of UHD required: 3.14.0.0
- Due to product compliance restrictions on products with TPM (Trusted Platform Module) components to a few countries, the USRP N320/N321 is available in two variants:
- Standard variant with TPM
- Non-TPM variant
Clocking and Sampling Rates
There are three master clock rates (MCR) supported on the N320/N321: 200 MHz, 245.76 MHz, 250 MHz
The sampling rate must be an integer decimation rate of the MCR. Ideally, this decimation factor should be an even number. An odd decimation factor will result in additional unwanted attenuation (roll-off from the CIC filter in the DUC and DDC blocks in the FPGA). The valid decimation rates are between 1 and 1024.
If the desired sampling rate is not directly supported by the hardware, then it will be necessary to re-sample in software. This can be done in C++ using libraries such as Liquid DSP [1], or can be done in GNU Radio, in which there are three blocks that perform sampling rate conversion.
Physical Specifications
Dimensions
(L × W × H)
- 35.71 cm × 21.11 cm × 4.37 cm
- 14.06 in. × 8.31 in. × 1.72 in.
Weight
- 3.13 kg
Drawings
N320
N321
Environmental Specifications
Operating Temperature Range
- N320 / N321: 0 to 50 °C
Storage Temperature Range
- N320 / N321: -40 to 70 °C
Operating Humidity Range
- 10% to 90% non-condensing
Schematics
N320/N321
- Motherboard: File:USRP N3XX MB Schematic.pdf
- Daughterboard: File:N32X Daughterboard Schematic.pdf
GPSDO
- Support GPSDO NMEA Strings
Sensors
You can query the lock status with the gps_locked sensor, as well as obtain raw NMEA sentences using the gps_gprmc, and gps_gpgga sensors. Location information can be parsed out of the gps_gpgga sensor by using gpsd or another NMEA parser.
Specifications
| Module Specifications | |
|---|---|
| 1 PPS Timing Accuracy from GPS receiver | <8ns to UTC RMS (1-Sigma) GPS Locked |
| Holdover Stability (1 week with GPS) | <±50us over 3 Hour Period @+25°C (No Motion, No Airflow) |
| 1 PPS Output | 3.3VDC CMOS |
| Serial Port | TTL Level, GPS NMEA Output with 1Hz or 5Hz update rate, Integrated into UHD |
| GPS Frequency | L1, C/A 1574MHz |
| GPS Antenna | Active (3V compatible) or Passive (0dB to +30dB gain) |
| GPS Receiver | 65 Channels, QZSS, SBAS WAAS, EGNOS, MSAS capable
Supports Position and Hold over-determined clock mode |
| Sensitivity | Acquisition -148dBm, Tracking -165dBm |
| TTFF | Cold Start: <32 sec, Warm Start: 1 sec, Hot Start: 1 sec |
| ADEV | 10s: <7E-011
10Ks: <2E-012 (GPS Locked, 25°C, no motion, no airflow) |
| Warm Up Time / Stabilization Time | <10 min at +25C to 1E-09 Accuracy |
| Supply Voltage (Vdd) | 3.3V Single-Supply, +0.2V/-0.15V |
| Power Consumption | <0.16W |
| Operating Temperature | -10°C to +70°C |
| Storage Temperature | -45C to 85C |
| Oscillator Specifications (internal) | |||
|---|---|---|---|
| Frequency Output of low Phase Noise crystal | 20MHz CMOS 3Vpp | ||
| 20MHz Retrace | ±2E-08 After 1 Hour @ +25°C without GPS | ||
| RF Output Amplitude | 3Vpp CMOS | ||
| 20MHz Phase Jitter (100Hz to 10MHz) | <0.135ps rms | ||
| Frequency Stability Over Temperature (0°C to +60°C) | ±0.1ppm (internal TCXO without GPS) | ||
| Warm Up Time | < 1 min at +25C | ||
| Phase Noise at 20MHz | 1Hz | -65 dBc/Hz | |
| 10Hz | -97 dBc/Hz | ||
| 100Hz | -116 dBc/Hz | ||
| 1kHz | -136 dBc/Hz | ||
| 10kHz | <-148 dBc/Hz | ||
| 100 kHz | <-155 dBc/Hz | ||
Datasheet
- Spec Sheet: http://www.jackson-labs.com/assets/uploads/main/LTE-Lite_specsheet_20MHz.pdf
- User Manual: http://www.jackson-labs.com/assets/uploads/main/LTE-Lite.pdf
FPGA
FPGA User Modifications
The Verilog code for the FPGA in the USRP N320/N321 is open-source, and users are free to modify and customize it for their needs. However, certain modifications may result in either bricking the device, or even in physical damage to the unit. Specifically, changing the I/O interface of the FPGA in any way, or modifying the pin and timing constraint files, could result in physical damage to other components on the motherboard, external to the FPGA, and doing this will void the warranty. The constraint files should not be modified. Please note that modifications to the FPGA are made at the risk of the user, and may not be covered by the warranty of the device.
Interfaces and Connectivity
N320
Front Panel
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Rear Panel
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Front Panel GPIO (N320 Only)
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The GPIO port is not meant to drive big loads. You should not try to source more than 5mA per pin. The +3.3V is for ESD clamping purposes only and not designed to deliver high currents. |
Power on state
The hardware power on state and UHD initial state for the front-panel GPIOs is high-Z. For the N320, there are no external pull-ups/pull-downs for the GPIO pins, but the FPGAs do have them and they are configured as follows: pull-down.
Pin Mapping
- Pin 1: +3.3V
- Pin 2: Data[0]
- Pin 3: Data[1]
- Pin 4: Data[2]
- Pin 5: Data[3]
- Pin 6: Data[4]
- Pin 7: Data[5]
- Pin 8: Data[6]
- Pin 9: Data[7]
- Pin 10: Data[8]
- Pin 11: Data[9]
- Pin 12: Data[10]
- Pin 13: Data[11]
- Pin 14: 0V
- Pin 15: 0V
Note: Please see the E3x0/X3x0/N3x0 GPIO API for information on configuring and using the GPIO bus.
N321
Front Panel
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- Additional details on the N321 Distribution Board can be found here: https://files.ettus.com/manual/page_usrp_n3xx.html#n3xx_rh_lo_sharing
Rear Panel
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Ref Clock - 10 MHz
Using an external 10 MHz reference clock, a square wave will offer the best phase noise performance, but a sinusoidal is acceptable. The power level of the reference clock cannot exceed +10 dBm.
PPS - Pulse Per Second
Using a PPS signal for timestamp synchronization requires a square wave signal with the following a 5Vpp amplitude.
To test the PPS input, you can use the following tool from the UHD examples:
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<args>are device address arguments (optional if only one USRP device is on your machine)
cd <install-path>/lib/uhd/examples ./test_pps_input –args=<args>
Certifications
RoHS
As of December 1st, 2010 all Ettus Research products are RoHS compliant unless otherwise noted. More information can be found at http://ettus.com/legal/rohs-information
China RoHS
Management Methods for Controlling Pollution Caused by Electronic Information Products Regulation
Chinese Customers
National Instruments is in compliance with the Chinese policy on the Restriction of Hazardous Substances (RoHS) used in Electronic Information Products. For more information about the National Instruments China RoHS compliance, visit ni.com/environment/rohs_china.
Certificate of Volatility
USRP N320/N321 Letter of Volatility
Downloads
Choosing a Host Interface
10 Gigabit Ethernet
Recommended 10 Gigabit Ethernet Cards
- Intel X520-DA2
- Intel X520-DA1
- Intel X710-DA2
- Intel X710-DA4
- Mellanox MCX4121A-ACAT
International Power Supply Options
The power supply provided with the USRP N320 kit is packaged with a power cord that is compatible with power outlets in the US/Japan. If you are not using the USRP N320 in the US/Japan, we recommend purchasing the International USRP N320 Power Cord set.
Option: USRP N320/N321 Rackmount
The USRP N320/N321 was designed to be used with a 1U Rackmount Assembly for building high-density MIMO systems in a compact and well-organized setup. This mount requires two compatible USRPs, and provides rubber standoffs between the USRPs to avoid both direct contact and surface scratching. If the user will be developing in a laboratory environment or building a high-channel count USRP system, then a 1U Rackmount Assembly is highly recommended. This specific mount is compatible with only the USRP N300, N310, N320, and N321, and allows the integration of up to eight bidirectional RF channels per 1U.
Guidance on SFP+ Adapters for Fiber Connectivity on USRP N320/N321
Ettus Research currently offers direct-connect, copper cabling accessories for the USRP N320/N321. However, it is also possible to use multi-mode fiber instead of copper connections for these devices. In this section, we will provide general guidance on the types of fiber adapters and cables that can be used with these products.
The USRP N320/N321 USRP is compatible with most brands of SFP+ fiber adapters. In some cases, other equipment in the systems such as 1/10 Gigabit Ethernet switches are only compatible with specific brands of SFP+ adapters and cables. As a general rule, we recommend checking compatibility with the switches and network cards in your system before purchasing an adapter.
Ettus Research does test the USRP N320/N321 USRP devices with our 10 Gigabit Ethernet Connectivity Kit and a Blade Networks G8124 1/10 GigE switch. Here are is a list of known-good cables and adapters.
Ettus Research has only tested multi-mode fiber accessories.
Known-Good Adapters
Known-Good Cables
Guidance on 10Gb SFP+ to RJ45 Adapters
Many new motherboards come equipped with an onboard 10Gb RJ45 NIC. It is possible to use a SFP+ to RJ45 adapter and operate at 10Gb speeds using a Cat6/7 Ethernet cables.
Ettus Research has tested the adapters linked below.
