A press release from the University of Southern California describes a novel transmission technique which can achieve very high data rates. The research led by Alan Willner of the USC Viterbi School of Engineering does not use a single carrier to send information but instead combines independent radio beams using a ‘spiral phase plate’ that twists each radio beam into a unique and orthogonal DNA-like helical shape. The receiver untwists the beams and recovers the different data streams. “Not only is this a way to transmit multiple spatially collocated radio data streams through a single aperture, it is also one of the fastest data transmission via radio waves that has been demonstrated,” Willner said.
Twisted RF beams achieve 32 GB/s - [Link]
Ondřej Karas of DoItWireless writes:
If You are interested in LED driving through RF, this article would be interesting for you. I tested own PCA9634 breakout board for this chip and wrote simple low level driver for IQRF TR-52D module. Next week, I am going to publish PC application for comfortable operation with that.
Wireless LED driver with PCA9634 - [Link]
HOPERF modules enable to gain a wireless data transfer or remote control of devices simply and without excessive costs.
A company, which specializes over a quarter of century on a given segment usually has experience and production capacities to develop and produce quality components. This is also a case of company HOPERF Micro-electronics and moreover – thanks to high production capacities the prices of their products are very attractive. HOPERF produces RF chips themselves, as well as read-made RF modules usable for virtually any application requiring a wireless control or data transfer, for example: remote keyless entry (RKE), control, security systems, telemetry, voice and data communication, control of processes and many others.
HOPERF modules offer besides a great price also a very high flexibility of usage. In contrast to many “fix-set” modules, RF modules HOPERF usually offer very wide possibilities to dynamically adjust many parameters, like for example: FSK/ OOK/ ASK modulation, possibility to work in a wide frequency range including free ISM bands 315, 433, 868 and 915MHz, while all main RF communication parameters are programmable.
In our stock can be found for example:
- RFM65CW-433S2 and RFM65CW-868S2 – 433/868 MHz FSK receivers. RFM65CW offers a unique possibility to use narrow-band and also wide-band communication modes. RFM65CW is optimized for a low power consumption while maintaining high sensitivity.
- RFM68CW-433S2 and RFM68CW-868S2 – 433/868 MHz FSK transmitters. It can be used without configuration from an MCU. However, in connection with MCU, it´s possible to change many parameters including output power, modulation format and a working channel.
- RFM73-S – 2,4 GHz transceiver, including a high power +20dBm version RFM73P-S2.
- RFM83C-433S1 – sophisticated 433 MHz ASK/OOK receiver including a version for low voltages RFM83CL-433S operating already from 2.1V
- RFM85W-433D – 433 MHz ASK transmitter. Excellent features and simple usage. Specially designed for remote control, car-alarms etc. working on 433.92 MHz.
- RFM12B-868S2P – multichannel 868 MHz FSK transceiver. RFM12B contains integrated functions of a digital data processing like: data filtering, clock recovery, data pattern recognition, integrated FIFO and TX data register. RFM12B enables to provide a clock for microcontroller.
HOPERF – universal RF modules for surprising prices - [Link]
We have already seen a number of ideas for tracking tags seeking funds on Kickstarter, most systems are limited by the range of Bluetooth communication with a smart device. This system from Iotera tackles the problem using cloud-based thinking: The basic wireless system consists of one or more tags or ‘iotas’ and a home base unit. Each 22 x 11 x 3 mm iota contains a chip, accelerometer, temperature sensor, speaker, RF transceiver, Bluetooth (unused so far) and a battery to give up to three months operation. Each iota communicates with the home base unit using wireless channels in the 902 to 928 MHz band giving a range of up to four-miles. Back home, the base unit receives the low-speed transmissions from the iota tag and forwards the information to a server via a Wi-Fi connection.
Novel Cloud-based Tag System - [Link]
Ondrej Karas of DoItWireless writes:
This is simple illustration how to build easy PWM LED control with IQRF TR module and a few other components.
This device is powered from 12V/6A DC power supply and can power up to 5m of LED strip. This device can be controlled via RF, buttons or potentiometer. RF controlling is compatible with remote control device RC-04 with low battery signalizing – fast 3 time LED blinking.
RF PWM LED control - [Link]
As promised we have built a transceiver USB dongle, for receiving data from various sensors like, smart meters, smoke detectors and temperature/humidity sensors. We’ll provide some code examples on how this trasciever can be used, and software for decoding data from diferent sensors enumerated above.
USB RF 433.92 MHz Transceiver module - [Link]
Instructables user Slomi posted this useful project on how to build a wireless indoor and outdoor thermometer using an Arduino! Via Embedded Lab.
This Arduino-based wireless thermometer uses two Arduino boards to measure indoor and outdoor temperatures. The outdoor Arduino board sends out the outdoor temperature measured by DS18B20 sensor to the indoor Arduino board using inexpensive 433MHz RF transmitter and receiver modules. The indoor Arduino board then displays the indoor and outdoor temperatures on a character LCD display.
Indoor/outdoor wireless thermometer using Arduino - [Link]
An introduction to why and when terminations are needed for transmission lines in both high speed digital applications and RF applications. 50 ohm termination examples are given, but the principles apply for other line impedances as well. The basic operating principles of signal propagation down a transmission line and the effects of reflections coming from improperly terminated are covered. Examples for digital-like signals as well as RF signals are given. A description and examples of what is meant by Standing Waves is also given. As a bonus, the properties of quarter wavelength transmission lines in RF applications is also presented.
Transmission Line Terminations for Digital and RF signals - [Link]
High-performance RF signal source family offers AM/FM/Phase modulation with I/Q modulation option
Fairport NY: Saelig Company Inc. (www.saelig.com) has introduced a high-performance RF signal source family, the DSG3000 3GHz/6GHz series, offering standard AM/FM/Phase modulation, as well as options for I/Q modulation and I/Q baseband output. The DSG3000 Series generates waveforms with high signal purity, typical phase noise of less than 110dBc/Hz@20kHz, and a wide output range of -130dBm to +13dBm. The DSG3000 RF signal generator has standard pulse modulation with an on/off ratio of up to 80dB, with an optional pulse train generator also available. The DSG3000 series has a typical amplitude accuracy of better than 0.5dB, and the standard 0.5ppm internal clock can be upgraded to an optional 5ppb high stability oven-controlled clock.
The DSG3000 series RF signal generators support internal and external modulation capabilities and operate with USB, LAN, LXI-C, and GPIB remote control interfaces. They also feature a wear-free electronic attenuator design and an automatic flatness calibration function via external automated power meter control over USB. This can be used as an automatic flatness calibration test system functionality for cables, attenuators, amplifiers, etc. The DSG3000ʼs standard 2U height is designed to save space when used with the optional rack mount kit.
Offering remarkable value for the money, the DSG3000 Series RF source is ideal for applications in wireless communication, radar test, audio/video broadcasting, as well as for general purpose, educational, and consumer electronics needs.
DSG3000 Signal Generators are made by RIGOL Technologies, a rapidly growing test and measurement company and the worldʼs second largest oscilloscope manufacturer by volume. RIGOL delivers high quality, high performance and value-priced test equipment for engineers, technicians and students worldwide. Offered with a remarkable 3-year warranty, the DSG3000 series is available now from Saelig Company, Inc. 1-888-772-3544 firstname.lastname@example.org
Saelig Announces Economical 3GHz/6GHz RF Signal Generator Series - [Link]
What’s inside Tektronix’s new MDO3000 Mixed Domain Oscilloscope? Dave does a teardown and looks at the circuitry and how they can get such a cheap 3GHz RF spectrum analyser to work.
EEVblog #587 – Tektronix MDO3000 Mixed Domain Oscilloscope Teardown - [Link]