RF category

ERASynth, An Arduino-Compatible RF Signal Generator

A young startup based in Istanbul has launched a crowdfunding campaign to bring its RF Signal Generator “ERASynth” into mass production. ERA Instruments is specializing in creating solutions in the areas of analysis, modelling, design and development of Communcation, RADAR and SIGINT systems.

ERASynth is a portable analog signal generator that generates RF frequencies from 250 kHz to 15 GHz. The output signal is produced using an advanced multiloop PLL architecture to minimize the phase noise and spurious. This clean signal can be used as a stimulus source for RF testing, an LO source for down-conversion or up-conversion, a clock source for data converters, and as a test signal source for software defined radio (SDR).

ERASynth Features & Specifications

  • Architecture: Multiloop Integer-N PLL driven by a tunable reference. No fractional-N or integer boundary spurs
  • Frequency Range:
    • ERASynth: 10 MHz to 6 GHz
    • ERASynth+: 250 kHz to 15 GHz
  • Amplitude Range: -60 to +15 dBm
  • Phase Noise: typical phase noise @ 1 GHz output and 10 kHz offset. -120 dBc/Hz for the standard version and -125 dBc/Hz the plus version.
  • Frequency Switching Time: 100 µs
  • Reference: Ultra-low noise 100 MHz VCXO locked to a ±0.5 ppm TCXO for standard version and ±25 ppb OCXO for the plus one.
  • MCU: Arduino Due board with BGA package Atmel Microcontroller (ATSAM3X8EA-CU)
  • Interfaces:
    • Wi-Fi interface for web-based GUI access
    • Serial-USB (mini USB) for serial access
    • Micro USB for power input
    • Trigger Input (SMA) for triggered sweep
    • REF In (SMA) for external reference input
    • REF Out (SMA) for 10 MHz reference output
    • RF Out
  • Dimensions: 10 cm x 14.5 cm x 2 cm
  • Weight: < 350 g (12.5 oz)
  • Power Input: 5 to 12 V
  • Power Consumption:
    • < 6 W for ERASynth
    • < 7 W for ERASynth+
  • Enclosure: Precision-milled, nickel-plated aluminum case
  • Open Source: Schematics, embedded Arduino code, Web GUI source code, and RS-232 command set

ERASynth is only 10 x 14.5 x 2 cm sized and it is consuming less than 7 Watts. It can be powered by a cell phone power-bank. Inclusion of an on-board Wi-Fi module and an open source web GUI makes ERASynth ideal for portable applications. Also its price make it affordable by everyone including makers, students, universities, research labs, and startups.

Compared with other low cost USB signal generators, ERASynth provides better features in many factors. It also delivers similar functionality of the professional RF signal generator with lower price. The tables below demonstrate the comparison.

The crowdfunding campaign on Crowd Supply will be closed by tomorrow, they raised about $35,000 of $25,000 goal. You can order your ERASynth for $500 and ERASynth+ for $750. More technical details are available on the campaign page.

Low-profile antennas can be mounted on metal surfaces

Julien Happich @ eedesignnewseurope.com discuss about a new low-profile 2.4GHz antenna that can be mounted on metal surfaces:

Antenova is shipping its first 2.4GHz antenna from its new Reflector series. The Zenon has been engineered to operate without de-tuning on metal surfaces or where the product housing is mainly metal.

The Reflector antennas are formed of two layers, one electrically isolated from the other, so as to provide RF shielding to the second layer. This means that the antenna can be placed on any kind of material and it will radiate effectively in the direction pointing away from the base material.

Low-profile antennas can be mounted on metal surfaces – [Link]

PandwaRF, A Portable Radio Analysis Tool

PandwaRF, is a portable low-power RF device that captures, analyses and re-transmits RF signals via an Android device or a Linux PC. It uses Bluetooth (BLE) or USB connection to transmit data in a simple and fast way, comes in the form of a controllable housing from a smartphone or a computer.

This pocket-size device operates at sub-1 GHz range, and it replaced the ‘standard SDR Grind’ of capturing, demodulating, analyzing, modifying and replaying by hand with a simple powerful interface.

The PandwaRF consists of a capable hardware device, tailored for beginners and advanced users, with an application that runs either on an Android device or on a PC. The Android interface provides full functionality to control and customize the PandwaRF easily using JavaScript.

Technical details of the PandwaRF:

  • Bluetooth Smart Module ISP130301, based on nRF51
  • CC1111 Low-Power SoC with Sub-1 GHz RF Transceiver
  • Multi frequencies (from 300 MHz to 928 MHz)
  • Multi modulation (ASK/OOK/MSK/2-FSK/GFSK)
  • Transmit and receive in half duplex mode
  • Support data rates up to 500 kBaud
  • Open hardware
  • Full speed USB: 12 Mbps (Linux or Android)
  • Bluetooth Smart 4.0 (Android/iOS)
  • USB charging & battery powered
  • 4 buttons to assign codes
  • 4 Status LEDs
  • 16 Mbit Flash Memory to save custom RF protocols
  • Rechargeable battery powered for stand-alone operation
  • Battery fuel gauge
  • RX amplifier for improved sensitivity: +13dB from 300MHz-1GHz
  • TX amplifier for higher output power: +20dB @ 433MHz & +17dB @ 900MHz
  • SMA connector for external antenna
  • Antenna port power control for external LNA
  • 22-pin expansion and programming header
  • Included: Battery and injection molded plastic enclosure

PandwaRF features are not fully complete yet, the developers had finished captured data processing offload, radio scripting (JavaScript & Python), RF packet sniffer, and spectrum analyzer. Other features are still in development process.

The device is available in three options, the Bare version is about $120 and comes without housing and without battery, the standard version is about $142 with battery and black case, in addition the extended version with enhanced features.

You can reach more information and order your PandwaRF on the official website.

Bluetooth Smart module is only 11x8x1.8mm

By Julien Happich @ eedesignnewseurope.com:

Amber wireless GmbH’s AMB2621 Bluetooth Smart module is a 2.4 GHz BLE wireless module based on the Bluetooth Smart 4.2 standard, measuring only 11x8x1.8mm and offered with or without integrated antenna.

Siglent SSA3032X Spectrum Analyzer Review & Experiments

Afroman reviews Siglent’s SSA3000X series spectrum analyzer and all the options. There is some RF information for beginners and usage experiments are also performed.

Siglent SSA3032X Spectrum Analyzer Review & Experiments [Link]

Send & Receive Radio With A Single Chip

Fitting transmit and receive capabilities of radio signals into one device may be impossible without using a significant filter, which is needed to isolate sent and received signals from each other.

The major obstacle to achieve that is the weakness of the received signal compared with the much stronger transmitted signal. However, researchers from Cornell University found their way to jump over this obstacle and created a two-way transceiver chip.

Alyosha Molnar, associate professor of electrical and computer engineering (ECE), and Alyssa Apsel, professor of ECE, had come up with a new solution to separate the signals. They made the transmitter consist of six sub-transmitters hooked into an artificial transmission line. Each one sends a weighted signal at regular intervals which combined with others such as a radio frequency signal in the forward direction, and at the same time they cancel each other in the opposite direction (towards to receiver).

The programmability of the individual outputs allows this simultaneous summation and cancellation to be tuned across a wide range of frequencies, and to adjust to signal strength at the antenna.

“You put the antenna at one end and the amplified signal goes out the antenna, and you put the receiver at the other end and that’s where the nulling happens,” Molnar said. “Your receiver sees the antenna through this wire, the transmission line, but it doesn’t see the transmit signal because it’s canceling itself out at that end.”

This research is based on a research reported six years ago by a group from Stanford University, which demonstrated a way for the transmitter to filter its own transmission, allowing the weaker incoming signal to be heard.

One of the sub-transmitter concept enhancements is that it will work over a range of frequencies, and instead of using a filter for every band, signal separation can be controlled digitally.

“You could have a single device that can be anything,” Apsel said. “You wouldn’t have to buy a new piece of equipment to have the newest version of it.”

You can find the full research at the IEEE Journal of Solid State Physics.

RFM69 output power

Bob @ electrobob.com tipped us with his latest article about RFM69 module.

As I was mentioning in my 1000.1000 Hardware selection, I have opted for the cool RFM69HW radio module. Weirdly enough, in quite a few sources (big distributor and ebay) the higher power HW module is cheaper. So there ie no reason not to get the higher power module, given quantity discounts. But I want it to operate at lower power most of times. The datasheet does not show any differences at lower power, so I had no reason not to go for the higher power module. It even says so on the features list on the front page, I can turn the power down to -18dBm.

RFM69 output power – [Link]

Teardown and analysis of microwave (26.5GHz) electro-mechanical step attenuators

Teardown and analysis of microwave (26.5GHz) electro-mechanical step attenuators from The Signal Path:

In this short episode Shahriar takes a close look at a pair of Hewlett Packard microwave electro-mechanical step attenuators operating up to 26.5GHz. Mechanical attenuators offer excellent repeatability, low insertion loss and nearly limitless linearity. The teardown reveals that the construction of both modules is very similar on the microwave path. In fact, the lower-frequency model still uses the same attenuator components. The newer model employs electronic control circuity while the older generation attenuator uses purely mechanically controlled DC path. Both models use a solenoid style actuators for step attenuation control.

Teardown and analysis of microwave (26.5GHz) electro-mechanical step attenuators – [Link]

NUT4NT, Open-Source 4-Channel GNSS Receiver Development Board

Although the industry of professional satellite navigation systems is limited to experts and large companies, Amungo Navigation is working towards bringing this industry to individual developers, small companies, and startups through its new open source platform NUT4NT.

NT1065 chip
NT1065 chip

NUT4NT is a development board which implements NT1065 chip with USB 3.0 interface. NT1065 is a Global Navigation Satellite System (GNSS) receiver designed by NTLab, a fabless microelectronic company. It is the first low-cost low-power RF front-end solution in the world. It also has 4 channels supporting all GNSS systems and bands.

GNSS receivers are electronic devices that receive and process signals from a GNSS satellite. These signals used to provide information about receiver’s position,velocity, and time.

NUT4NT has two different working modes. The first uses dual inputs and acts as a centimeter level precision positioning tool, without the need of high quality antenna. The other mode uses the four inputs and provides an array antenna processing system to simply reduce interference and noise.

Dual Inputs Mode (Left) - Four Inputs Mode (Right)
Dual Inputs Mode (Left)   –   Four Inputs Mode (Right)

Hardware and software specifications of NUT4NT:

  • Receiver chip: NT1065
  • USB 3.0 controller: CYUSB3014
  • Clock rate: 10 MHz
  • RF inputs: two or four, depending on board option
  • RF inputs referred Noise Floor: 1 dB
  • ADC resolution – two-bit
  • ADC frequency – up to 99 MHz
  • Samples transfer – continuous full stream, from 20 to 100 Mbytes/sec
  • Power: 5V @ 0.5 A from USB or external adapter
  • Size: 70x50x20 mm (early board) / 77x122x25 mm (single board)
  • All GNSS systems: GPS, GLONASS, Galileo, BeiDou, IRNSS and future
  • All GNSS band: L1/L2/L3/L5, G1/G2/G5, B1/B2, E1/E5 and future
  • Four-channel synchronous reception for antenna array processing
  • Signal dumper (grabber) software
  • Spectrum analyzer software
  • NT1065 configuration software
  • Supports libusb API
  • Supports native Cypress driver API
  • Software for Windows, Linux, and potentially all other OS’s with libusb

There are two options of NUT4NT boards, the Early Board and the Single Board.

Early Board is for $399 and there are only limited boards to order through the crowdfunding campaign page. It consists of two separated boards: the base board, which has the USB 3.0 controller, and NT1065 submodule board.

Single Board will be available later as a future plan, and it is said to have  only one board instead of two.

NUT4NT Early Board
NUT4NT Early Board

NUT4NT is an open source project. Software sources are available on github and the hardware’s documentation will be available soon.

More information and details about the product with many accessories are reachable on the product crowdfunding page.