Bingo! - Now where can I start buying this stuff??
Now before the naysayers start talking about poor RF
performance because this concept would use <gasp> -
computers, I want to stress this technology is in
addition to, not instead of good RF design practices.
The two need not be mutually exclusive! And there
would be no reason not to have traditional radio
panels as options that interface to the same network,
- so you can have it both ways.
I would however lean toward sticking to generic
Ethernet for everything, either copper (in the shack),
or glass for those tower mounted microwave bands.
Modules for 10 and 2 Meters would allow everyone
already using high performance transverters a way to
quickly adopt this technology without having to scrap
their entire existing station and starting over.
Also it must be acknowledged that we as weak signal
types will always be pressing the limits of A to D
technology in terms of S/N ratio and accuracy as well
as dynamic range. This is true irregardless of the
actualmodes we use.
Duane
N9DG
--- Ward Silver <hwardsil@centurytel.net> wrote:
> Not being a big-time VHF/UHF contester, please
> discount my opinion
> appropriately, but I'm a systems guy and we can't
> pass up this sort of
> discussion :-)
>
> Here's an entirely different architecture for the
> radio. Some requirements
> that the new architecure addresses:
>
> - reduces low-loss feedline needs, particularly
> above 450 MHz
> - provides a full digital interface for the User
> Interface
> - provides for firmware upgrades and
> software-defined-radio features, such
> as new modulation and data protocols
> - allows TCP/IP connectivity to the Internet
> - provides for third-party and independent software
> development
>
> Within this architecture, the "radio as box"
> disappears in favor of a
> distributed system of RF, processing, and UI
> subsystems. Nothing prevents
> the user from assembling the three subsystems into a
> single physical unit.
> This doesn't work all that well as a single all-band
> rig in a single
> enclosure, but makes assembling a fixed station
> easier and cheaper.
>
> To support this architecture:
>
> 1) The RF receive front-end should
> - be capable of being completely remote-able as
> a unit, including
> outdoor installation at the tower-top
> - be sufficiently configurable to optimize
> dynamic range or sensitivity
> - have common single-frequency downlink at a
> frequency (different from
> rx) low enough to result in a large savings of
> feedline costs
> - be capable of full-QSK single-band operation
> with a high-power
> amplifier located in the shack
>
> 2) The RF PA should
> - be capable of being completely remote-able as
> a unit, including
> outdoor installation at the tower-top
> - be capable of full-QSK
> - have common single-frequency uplink at a
> frequency low enough
> (different from tx) to result in a large savings of
> feedline costs
> - be sufficiently configurable to optimize
> performance for individual
> modulation schemes
>
> 3) The Processing subsystem should
> - have an advanced DSP modulator and demodulator
> capable of anything
> from CW to advanced I/Q schemes
> - have a two-way digital high-speed (<1 msec
> event resolution) control
> interface to the external modules
> - have a public software interface for
> independent developers
> - have a single-cable interface to the RF
> subsystem with the option of a
> standalone control interface
> - be capable of switching between several
> different RF subsystems with
> full duplex operation
>
> 4) The User Interface should be either a standalone
> traditional front-panel
> or a user-definable PC-based OS-independent
> interface
> - the PC-based interface should include
> - TCP/IP connectivity to the Internet to
> support transparent remote
> operation
> - standard connectivity to audio generation
> and processing
> interfaces (i.e. - sound card)
> - a public software interface
> - support wireless human interfaces such as
> Bluetooth
> - the interface between the UI and Processing
> subsystems should be a
> Fast Ethernet or WiFi interface to a PC or
> standalone front panel
>
> Obviously, there is lots more that could be added.
>
> What about a fully digital interface to the RF
> subsystem using Firewire or
> something similar? That also works. The tradeoff
> would likely be a more
> expensive remote box and possibly a more complex
> interface involving
> amplifiers. It's also possible that with a
> sufficiently high-speed A/D
> converter, the processing subsystem could be
> subsumed into a PC, although
> the hardware interface might be problematic.
>
> Oh well, it's fun to think about!
>
> 73, Ward N0AX
>
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