My answer is very short. Words have meaning.
Software Defined Radio Software defines how the radio functions. It's not a CPU Defined Radio or a Program Running Defined Radio. There are people that argue that a DSP is not a computer, but they are plain wrong. Verilog and VHDL are programming languages that can run on your PC or define how a FPGA functions. If the FPGA controls the radio, your Verilog software is defining how your radio behaves hence SDR. But so be it, don't put FPGA's in your SDR radio, I will. At 07:45 AM 6/14/2006, you wrote: >I have listed where I have got it and where anybody can get it from, >read it and understand what SDR is. > >Why do you think it is restrictive? > >SDR is an evolution of the traditional concept of a radio. >Therefore we have to make some distinctions to come to a more >detailed understanding of what it is. > >For a long time we had analogic radio circuitry only. >Then some parts have been digitalised as e.g. the VFO with the >advent of PLL and its programmable divider stages, the >electrooptical tuning knob etc.. >Note, having something digital in a electronic circuit doesn't mean >to have software running! > >Next it has been introduced the microcontroller to control display >circuitry, to electronically switch of various functions (already >made of analogic circuits) as mode, PTT, tune and some sort of >telecontrol through an interface port (often a RS-232). > >At this stage of the radio evolution, SDR is not involved, yet, due >to the fact there is still no software signal processing but >(tele)control of the radio's hardware parts only. > >The successive step relates to the first DSP applications on >processing to filter the audio signals coming from the BF stages of a RTX. > >This can be considered the first phase of Software Defined Radio >because *software processes*, and not simply digital circuits >technology!, substitutes a part of the radio circuit. > >The further step, and second SDR implementation phase, has been made >by the introduction of DSP into the IF stages due to availability of >more powerful DSP cores. > >I'll underline that remote as local control of circuits has nothing >to do with SDR either if it is performed by a PC or by local >processors in the RXT box! > >SDR is the technology of elaborating the to be received signals >through software running on one or more microprocessing units (it is >unimportant if it resides on the PC or on a DSP in the radio box). > >As I've stated in my precedent e-mails FPGAs are reconfigurable >hardware circuits, not software processing units! For this reason >FPGA cannot be considered part of an SDR. >They are *hardware substituting some other hardware* and convenient >in a context of a reconfigurable hardware radio. >The fact they are reconfigured (reprogrammed) using some software on >a PC doesn't mean that FPGAs process radio related signals by running software. > >In other words, local or remote radio control is not SDR. >SDR is treating, converting, modifying a received signal by the use >of a software program instead of traditional electronic circuitry, >nothing else. > >If this concepts, in your opinion, aren't still addressing the >points then I apology for this and invite you to take a view to the >rich documentation I have mentioned before. > >vy 73s de Andreas Troschka - ik2wqi > >[EMAIL PROTECTED] wrote: > > You missed my point, where did you get your definition of a SDR radio, > > it seems awfully restrictive. > > > > A PC, A DSP, and a FPGA are all controlled by "Software" that defines > > what they do, so they are all "Software Defined Radios" > > > > > > >Yahoo! Groups Links > > > > Cecil Bayona KD5NWA www.qrpradio.com "Windows, the most successful software virus ever" Don Seglio Batuna ------------------------ Yahoo! Groups Sponsor --------------------~--> Home is just a click away. Make Yahoo! your home page now. http://us.click.yahoo.com/DHchtC/3FxNAA/yQLSAA/ELTolB/TM --------------------------------------------------------------------~-> Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/soft_radio/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
