I love the Xilinx FPGA's I have a Diligent Spartan 3 development kit with the XC3S1000 upgrade, that is a great board to play with.
I also agree with you agreeing with me, see I can be nice and friendly. At 11:46 AM 6/14/2006, you wrote: >Cecil, > >I agree with you 100%. The concept of a "Software Defined Radio" >means just that. The function of the radio is defined by software. >SDR does not restrict what sort of hardware the operative software operates on. > >A CPU (optimized for DSP or not) may execute instructions that >define how the radio signal is processed (demodulated, filtered, >decimated or whatever). By the same token, a FPGA may be configured >(utilizing Verilog or other language) in such a manner that the FPGA >also processes a digitized radio signal. The processing may include >those sorts of processes that a dedicated CPU may perform albeit >usually much more efficiently and at higher speeds. > >Then there is the concept of a soft CPU that is defined within a >FPGA. That CPU could be of a CISC or RISC architecture and could >execute essentially the same programs an equivalent stand-alone >processor could while the remainder of the FPGA is configured to >perform some other dedicated tasks. > >If a radio's functionality is defined by software it is a SDR with >no distinction being made whether the hardware that performs the >signal processing is a general purpose CPU, a CPU optimized for DSP >functions or a FPGA configured to perform certain signal tasks. > >I get the impression the original poster is confusing a "software >controlled radio" with a "software defined radio". There is indeed a >world of difference between those two. > >A "software controlled radio" may be a conventional receiver >constructed with analog parts that is controlled in the sense that >some CPU commands the selection of filter bandwidths, the selection >of oscillator frequencies, the selection of gain settings or >whatever. They key concept is that the RF signal processing in this >case is by means of conventional analog approaches and the CPU only >controls certain settings of the hardware. This is in contrast to a >SDR where the software is the radio. (change the software and change >the signal processing). > >73 Ray WB6TPU > > >Disclaimer: yes I work for Xilinx, a major FPGA provider, but that >doesn't have any effect on my previous statements. > > > >---------- >KD5NWA wrote: > > >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 > >> > ><mailto:kd5nwa%40cox.net>[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" > >> > Cecil Bayona KD5NWA www.qrpradio.com "Windows, the most successful software virus ever" Don Seglio Batuna [Non-text portions of this message have been removed] ------------------------ Yahoo! Groups Sponsor --------------------~--> Everything you need is one click away. Make Yahoo! your home page now. http://us.click.yahoo.com/AHchtC/4FxNAA/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/
