You can find on the Internet and in some technically tailored bookstores a lot of documentation as studies, e-books and books discussing what a SDR is. Some universities have R&D projects on progress on this item and many papers can be obtained from them visiting their institutional web servers. Telecom companies are continuously researching on SDR and sometimes technical documentation can be found through specific channels (e.g. contacting the insiders). This companies develope the most advanced *applied* SDR architectures (maybe military and space projects are better but they use proprietary HW we are not able to reach).
>From the conceptual point of view, DSPs as other microprocessors are actually >the only way to have software substituting the radio's hardware. FPGAs are reconfigurable hardware that substitutes many ICs in one package. Sometimes it is possible to configure a FPGA to substitute algorithms usually processed by software programs with hardcoded logic. Due to the fact that the aim of SDR is to put the more hardware of a radio into software processing, actually the only components enabling to do this in a considerable amount are microprocessors. I'm saying "actually" because new revolutionary technologies are on the way. One of these is the introduction of RCPs, Reconfigurable Communication Processors, which are based on the merge of one or more DSP cores and a new type of on the fly reconfigurable device, far parent of the concept of the ancient FPGA technology. This processors are able to change their configuration during elaboration in a couple of machine cycles without loose of data, that means software can change the characteristics and architecture of the SDR near to instantly. Such a device can introduce software computing from as near as the antenna connector (even if I'll always sustain that a sort of preselector is inevitable!) down to the speaker and from mike up to the RF PA in the opposite direction. The same device may serve as SD RX and as SD TX. So getting a look on what happens outside the HAM world will reveal some interesting new experiment opportunities. Andreas - ik2wqi KD5NWA wrote: > Where did you get what the definition of a SDR is? What is the > difference between the software in a PC a DSP or a FPGA, don't they all > use a defined program to make a machine behave in a described way? > ------------------------ 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/
