SDRA Programme 02.06.2018
10:00 - 10:30 Welcome & Introduction
Prof. Dr. Michael Hartje DK5HH, Markus Heller, M.A. DL8RDS
10:30 - 11:00 Transmitter architectures for high efficiency amplification using PowerSDR software and Hermes firmware
Rüdiger Möller DJ1MR
Currently used RF power amplifiers consume large amounts of energy, dissipate heat and take up space. Large heatsinks are increasing the weight and the expenses of the PA. I would like to present a project to you that I have been working on for some time together with Phil, VK6PH, and Warren, NR0V, to overcome these shortcomings.
11:00 - 11:30 An update on OpenHPSDR software for Linux
John Melton G0ORX/N6LYT
The Radioberry (v2.0) card designed by Johan Mass, PA3GSB, that can be used with a custom version of piHPSDR as a standalone transceiver or using a HERMES emulator that runs on the Raspberry Pi to allow it's use with PowerSDR and other SDR software. An introduction to the development of a new Linux application that supports multiple receivers, supports both Protocol 1 and Protocol 2 and uses PulseAudio which allows connection to applications like WSJT-X without cables.
11:30 - 12:00 Status of DFC (Direct Fourier Conversion)
Phil Harman, VK6PH
The majority of current Software Defined Radios (SDRs) use a Direct Down Conversion (DDC) technique in order to convert an RF signal to Baseband. This normally consists of a complex digital mixer followed by CIC filters then a FIR compensating filter. An alternative approach is to use Direct Fourier Conversion (DFC). This has a number of advantages including simpler, and hence lower cost, hardware plus the need to program in a Hardware Description Language is removed. The presentation will provide an update as to the status of the Minerva DFC project hardware and software.
12:00 - 12:30 WDSP 2018 - What's new? (low latency filtering, PS2.0, new transmit audio tools)
Dr. Warren C. Pratt, NR0V
New magic in the open-source WDSP library -- sharp FIR filters without the latency, a rack of pro audio equipment built in software, PureSignal 2.0 dealing with "difficult" amplifiers, and Adaptive Resampling to cross clock domains without the under-flows/over-flows.
12:30 - 13:00 Lunch Break
13:00 - 13:30 The OVI40 / UHSDR Project - Part I - Developing An Open Standalone SDR
Andreas Richter DF8OE, Danilo Beuche DB4PLE, Michael Wild DL2FW, Frank Dziock DD4WH
OVI40 is an Open Source standalone homebrew SDR TRX project (VLF to 2m), developed with the aim of being modular and future-proof. The talk describes the hardware and the UHSDR software including a discussion on the evolution from the “single-system” software used for the well-known mcHF (initially written by Chris M0NKA and Clint KA7OEI) to the multi-SDR approach in the UHSDR software project.
13:30 - 14:00 The OVI40 / UHSDR Project - Part II - Getting the Most Out Of Your Signals - Digital Signal Processing in UHSDR Firmware
Michael Wild DL2FW, Frank Dziock DD4WH, Andreas Richter DF8OE, Danilo Beuche DB4PLE
We give an overview of the digital signal path and a detailed view into some of the DSP components of the open source UHSDR software written in C for small MCUs like STM32F4 and STM32F7. The UHSDR has its origin in the mcHF software (initially written by Chris M0NKA and Clint KA7OEI) and has been extensively modified and extended since then. It now supports voice modes (SSB, AM, FM, FreeDV), digital modes with coding and decoding (CW, BPSK, RTTY) and signal optimization features, eg. noise reduction and noise blanking.
14:00 - 14:30 A New Monitor system for electromagnetic inference (EMI) of the environment using Redpitaya
Prof. Dr. Michael Hartje DK5HH, Univ. Appl. Sc. Bremen
The shortwave spectrum contains 5,2 MHz of amateur radio bands. In populated areas the low voltage grid partly causes high amplitudes of interferences. This talk presents a measurement system based on Red Pitaya which is able to survey and record interferences in the above named frequencies and correlate them in the time domain. Also, the minimum level of interferences will be measured.
14:30 - 15:00 Transceiver Experiments and Measurements from 1 MHz up to 3,8 GHz using LimeSDR
Prof. Dr. Michael Hartje DK5HH, Univ. Appl. Sc. Bremen
This talk is on usage possibilities and capailities of the LimeSDR platform-. The LimeSDR has a frequency range of 0.1 – 3.8 GHz. This talk explains measurements and small code examples.
15:00 - 15:30 A control console for PC Based SDR
Laurence Baker G8NJJ, Kjell Karlsen LA2NI
The paper describes a control console for a popular PC based Software Defined Radio application, “PowerSDR”. Software Defined Radio has demonstrated substantial performance benefit over conventional signal processing, but the implementation has often forced users towards a windows GUI screen rather than conventional controls. The “Odin” console has been developed to give the user the “look and feel” of a conventional radio with rotary controls, illuminated pushbuttons and a simple touchscreen display. The console interacts with PowerSDR using CAT messages and allows the user to have immediate access to all the commonly needed controls. It has been designed to mimic operation with high-end conventional radios – for example allowing the tuning knob to be turned at several rotations per second with a high resolution optical sensor.
15:30 - 16:00 Building a demo SDR application using a lightweight synchronous data flow framework
Dr. János Selmeczi, HA5FT
With the new data flow based sdrflow language and compiler we could construct an sdr application from a set of signal processing algorithm written in C language just as easily as drawing block diagrams. In fact the language is the text base equivalent of the hierarchical block diagrams. The language is declarative and allows to define not only the signal flow but the the control parameter flow too. The compiled code is executable by a lightweight runtime system. The runtime system could be implemented on PCs under linux or windows, small embedded processors (PIC32, ARM Cortex M4), on ARM based linux systems and hopefully on GPUs.
16:00 - 16:30 Let's code a simple receiver in C
András Retzler, HA7ILM, Univ. Budapest
For using SDR in amateur radio applications, it is easier to use existing receiver software, or create GNU Radio flowgraphs with pre-built blocks. On the contrary, in the do-it-yourself spirit of amateur radio, this talk will guide you through the steps of implementing a simple AM/FM/SSB receiver from scratch, in plain old C, from understanding the basic DSP concepts to actually writing the code, in order to get a deeper understanding of what happens actually under the hood in popular SDR software. The talk builds on the author's learning experience of creating the open source CSDR command line tool, which is used for DSP in the OpenWebRX web based SDR receiver.
17:00 - 17:30 Adaptive FBMC Real-Time Testbed based on GNU Radio
Maxim Penner, DJ1MP, Univ. Hannover
An SDR-based testbed is presented, build with GNURadio. It demonstrates a Filter Bank Multicarrier (FBMC) transceiver chain. FBMC is a generalization of OFDM, currently the most popular modulation scheme used in LTE and WLAN. The testbed transmits frames with non-rectangular pulse shapes and synchronizes in frequency domain.
17:30 - 18:00 Sigma Shift Keying: A Paradigm Shift in Digital Modulation Techniques
Martin Kramer DH3FR, Univ. Siegen
A new digital modulation technique, named Sigma Shift Keying (SSK), is introduced. Standard deviations of zero mean Gaussian noise signals are being digitally modulated instead of shift keying of sinusoidal carrier signals. This creates a new aspect of future communication methodes and enhancements of existing modulation techniques.