TI2AEB
04-23-2008, 02:54 AM
Dear Collegues:
Normally we have to suffer qrm in our HF bands.
Our modulation technics has been unchanged for decades.
Around the year 1960 (some 48 yrs ago) the big change: from am to ssb.
A truly reduction of bandwith. Since then, in the voice region, no major changes, except excellent receivers with variable digital filters, DSP., etc
But still in the world of the ancient AM.
Why not to try digital schemes, like an"amateurized CDMA" ?
Not enought spectrum in HF ?Well, with amateur CDMA we will not cause qrm to the analog existing stations. Neither they will cause qrm to us.
In the citizen band of 2100 or 2300 Mhz, there are a lot but a lot of CDMA links, working free of problems. Very near each other
I possible I would like to hear the opinion of a designer of CDMA equipments.
Can we design like a kind of amateur CDMA ?
73
Armando
TI2AEB
San Jose, Costa Rica
Normally we have to suffer qrm in our HF bands.
Our modulation technics has been unchanged for decades.
Around the year 1960 (some 48 yrs ago) the big change: from am to ssb.
A truly reduction of bandwith. Since then, in the voice region, no major changes, except excellent receivers with variable digital filters, DSP., etc
But still in the world of the ancient AM.
Why not to try digital schemes, like an"amateurized CDMA" ?
Not enought spectrum in HF ?Well, with amateur CDMA we will not cause qrm to the analog existing stations. Neither they will cause qrm to us.
In the citizen band of 2100 or 2300 Mhz, there are a lot but a lot of CDMA links, working free of problems. Very near each other
I possible I would like to hear the opinion of a designer of CDMA equipments.
Can we design like a kind of amateur CDMA ?
73
Armando
TI2AEB
San Jose, Costa Rica