[digitalradio] What is SS and what it is good for to HAMs, was: ARRL/FCC Announcement
I did not follow the whole conversation. Anyway, spread spectrum has following benefits as far as I am known: It allows more stations to use the spectrum. The trick is in spreading the signal by a sequence, which appears to be random. Many stations transmitting spread spectrum signals at various time and frequency offsets will all together resemble white noise. On the contrary, many conventional narrow band signals will approach white noise much slower. There is a classic article from Costas (of the PSK Costa's loop decoder algorithm) explaining why even DSB has theoretical benefits over SSB because it spreads the signal to higher bandwidth, which makes the total interference look more like white noise. The spreading in frequency makes the signal less sensitive to narrow band carriers, it makes it difficult to jam a signal by a single or couple of carriers. The other benefit is critical to military use. It is difficult to detect and if one does not know the spreading sequence, it is impossible to decode. Spread spectrum somehow contradicts the HAM radio philosophy. Spread spectrum to be useful mandates the software itself to identify and lock to the signal. It is impossible identify weak SS signal from white noise by ears. The operator will just enumerate the channels and the machine will do the rest. Higher amount of SS stations at the same frequency will increase background noise, so it will create an interference to let's say a CW operator. Therefore one would need to dedicate SS channels, otherwise there would be plenty of complaints from CW operators. I don't see a real benefit in running SS signal in just 2.5kHz SSB bandwidth. Olivia or MFSK will do better because they use the whole spectrum for itself, while SS on purpose leaves all the orthogonal spreading sequences to be used by other stations. For the same bandwidth, SS is designed to share frequency, classic multitone signals for best coding gain. That is a whole world of difference. SS would be very beneficial for beacon network, where all beacons share the same channel. This is what the GPS satellite network does indeed. SS may be used for single channel world wide chatting mode. One will be able to decode many signals at once with powerful computer. 73, Vojtech OK1IAK
Re: [digitalradio] What is SS?
The document that the author of ROS originally published, Introduction to ROS: The Spread Spectrum, contains a good description of frequency-hopping spread-spectrum (FHSS) techniques. Section 4 describes taking a 250 Hz wide mode (MFSK16) and spreading it over 2 kHz by shifting the center frequency in a pseuorandom sequence. The receiver changes frequencies in the same sequence and the logic used to detect a special tone sequence to obtain synchronization is described in section 5. The amount of spectrum occupied increases by a factor of 8. FHSS is one way to minimize the effects of multipath spread but there are also other techniques that occupy less spectrum. Note that the author of ROS published a second doucument,ROS Technical Description, that contains elements of the original but does not mention FHSS and omits any description of how data is mapped to tones. Users comparing the original and later versions of the code haven't seen a difference in the transmitted spectrum. 73, John KD6OZH - Original Message - From: Rein A To: digitalradio@yahoogroups.com Sent: Friday, March 05, 2010 19:16 UTC Subject: [digitalradio] What is SS? Here is a reprint that for my limited mental capacities defines the core quite well. I have asked Mike the author for some references, no lack of trust though. - -Original Message- From: n4qlb n4...@... Sent: Mar 5, 2010 1:15 PM To: rosdigitalmodemgr...@yahoogroups.com Subject: [ROSDIGITALMODEMGROUP] Re: How do you like ROS Now? Thank You for your comments Sig. Let me explain what SS is. Spread spectrum is a method by which a bank of channels (Frequencies)are designated between a Transmitter and Receiver and are shared or (Frequency Hopped) to facilitate a clear Transmisson. The Transmitter actually signals the Receiver to Hop from one frequency to another. A good example is a 900mhz digital cordless telephone or a 800Mhz digital radio truncking system. (Motorla Astro). A frequency in Ham radio consist of a 3kh wide channel. Ros does not signal a receiver to hop outside of that channel (3 Khz) therefore it is not SS and is just like anyother FSK mode used in the amatuer radio service. The ease of obtaining a License in the U.S. by people that are not technically qualified to hold one is the main culprit regarding the controversy over new modes such as ROS. I am confident that all variations of ROS are perfectly legal in the U.S.
Re: [digitalradio] What is SS?
Hi John I can confirm .There is no difference in the transmitted spectrum. Here some comparing done with DL4YHF's Spectrum Lab ROS v2.6.1 x's http://home.broadpark.no/~saanes/bilder/ROS%20v2.6.1_xxx.jpg Idling http://home.broadpark.no/~saanes/bilder/ROS%20v2.6.1_idling.jpg ROS v1.6.2 x's http://home.broadpark.no/~saanes/bilder/ROS%20v1.6.2_xxx.jpg Idling http://home.broadpark.no/~saanes/bilder/ROS%20v1.6.2_idling.jpg la5vna Steinar On 06.03.2010 10:00, John B. Stephensen wrote: The document that the author of ROS originally published, Introduction to ROS: The Spread Spectrum, contains a good description of frequency-hopping spread-spectrum (FHSS) techniques. Section 4 describes taking a 250 Hz wide mode (MFSK16) and spreading it over 2 kHz by shifting the center frequency in a pseuorandom sequence. The receiver changes frequencies in the same sequence and the logic used to detect a special tone sequence to obtain synchronization is described in section 5. The amount of spectrum occupied increases by a factor of 8. FHSS is one way to minimize the effects of multipath spread but there are also other techniques that occupy less spectrum. Note that the author of ROS published a second doucument,ROS Technical Description, that contains elements of the original but does not mention FHSS and omits any description of how data is mapped to tones. Users comparing the original and later versions of the code haven't seen a difference in the transmitted spectrum. 73,
Re: [digitalradio] What is SS? Senor Ros is not an honest person !
Dear amigos: I am really concerned about the damage to the amateur radio hobby generated by a NON AMATEUR in Spain that wrote a software program for a new digital mode that very clearly to me, without any doubts , is a FHSS communications mode. I wrote e-mail messages to this person, and received some very aggressive replies from him... he even used several bad words in his messages that show that besides his very primitive knowledge of the English language _ ( he can not communicate effectively using English, as he has demonstrated many times with this very poorly written postings ) he lacks the most basic education and ethics. The topic we are dealing now is not, in my humble opinion, if ROS is or is not FHSS, it this person sent messages explaining or attempting to explain the nature of the ROS software, and then when faced with clear evidence that part of the market , and a signficant one indeed , to which he was aiming, could not make use of the ROS software. Now we are seeing on the 20 meters band, under better propagation conditions due to the so far sustained increase in solar activity, that Olivia users are facing interference from ROS users, caused by the ignorance of the Spanish inventor about amateur radio. He replied to a senior Cuban professor, a very prestigious telecommunications expert, using what could be described as foul language, an indication that confirmed that he was not only answering to my advice in such a disrespectful language. Just to add one more element... when I asked him about the possibility of writing the ROS software for LINUX users, his answer was also a clear demonstration of his ignorance about today's world. So, amigos at digital radio , my advise , and that's what I am going to do, is to alert ROS users of the possibility that the author of the software may even be attempting to use it for other purposes that are not related to amateur radio... After all, once you load a program of which you don't known the source code, into your computer, you are at the mercy of those who wrote the computer code... 73 and DX Arnie Coro CO2KK IARU Region II Area C Emergency Coordinator --- On Sat, 3/6/10, John B. Stephensen kd6...@comcast.net wrote: From: John B. Stephensen kd6...@comcast.net Subject: Re: [digitalradio] What is SS? To: digitalradio@yahoogroups.com Date: Saturday, March 6, 2010, 4:00 AM The document that the author of ROS originally published, Introduction to ROS: The Spread Spectrum, contains a good description of frequency-hopping spread-spectrum (FHSS) techniques. Section 4 describes taking a 250 Hz wide mode (MFSK16) and spreading it over 2 kHz by shifting the center frequency in a pseuorandom sequence. The receiver changes frequencies in the same sequence and the logic used to detect a special tone sequence to obtain synchronization is described in section 5. The amount of spectrum occupied increases by a factor of 8. FHSS is one way to minimize the effects of multipath spread but there are also other techniques that occupy less spectrum. Note that the author of ROS published a second doucument,ROS Technical Description , that contains elements of the original but does not mention FHSS and omits any description of how data is mapped to tones. Users comparing the original and later versions of the code haven't seen a difference in the transmitted spectrum. 73, John KD6OZH - Original Message - From: Rein A To: digitalradio@ yahoogroups. com Sent: Friday, March 05, 2010 19:16 UTC Subject: [digitalradio] What is SS? Here is a reprint that for my limited mental capacities defines the core quite well. I have asked Mike the author for some references, no lack of trust though. - - - - - -Original Message- From: n4qlb n4...@... Sent: Mar 5, 2010 1:15 PM To: ROSDIGITALMODEMGROU p...@yahoogroups. com Subject: [ROSDIGITALMODEMGRO UP] Re: How do you like ROS Now? Thank You for your comments Sig. Let me explain what SS is. Spread spectrum is a method by which a bank of channels (Frequencies) are designated between a Transmitter and Receiver and are shared or (Frequency Hopped) to facilitate a clear Transmisson. The Transmitter actually signals the Receiver to Hop from one frequency to another. A good example is a 900mhz digital cordless telephone or a 800Mhz digital radio truncking system. (Motorla Astro). A frequency in Ham radio consist of a 3kh wide channel. Ros does not signal a receiver to hop outside of that channel (3 Khz) therefore it is not SS and is just like anyother FSK mode used in the amatuer radio service. The ease of obtaining a License in the U.S. by people that are not technically qualified to hold one is the main culprit regarding the controversy over new modes such as ROS. I am confident that all variations
Re: [digitalradio] What is SS? Senor Ros is not an honest person !
On Sat, Mar 6, 2010 at 9:12 AM, Arnaldo Coro acoro33...@yahoo.com wrote: So, amigos at digital radio , my advise , and that's what I am going to do, is to alert ROS users of the possibility that the author of the software may even be attempting to use it for other purposes that are not related to amateur radio... After all, once you load a program of which you don't known the source code, into your computer, you are at the mercy of those who wrote the computer code... 73 and DX Arnie Coro CO2KK Yikes! That would not be good. Andy K3UK
Re: [digitalradio] What is SS? Senor Ros is not an honest person !
Thanks for the caution, Arnie. I will definitely scan my computer for viruses and trojans after installing running loading ROS. The fact that it already sends automatic emails makes one imagine what else might be possible once I have configured it with my email address! 73 - Skip KH6TY Arnaldo Coro wrote: Dear amigos: I am really concerned about the damage to the amateur radio hobby generated by a NON AMATEUR in Spain that wrote a software program for a new digital mode that very clearly to me, without any doubts , is a FHSS communications mode. I wrote e-mail messages to this person, and received some very aggressive replies from him... he even used several bad words in his messages that show that besides his very primitive knowledge of the English language _ ( he can not communicate effectively using English, as he has demonstrated many times with this very poorly written postings ) he lacks the most basic education and ethics. The topic we are dealing now is not, in my humble opinion, if ROS is or is not FHSS, it this person sent messages explaining or attempting to explain the nature of the ROS software, and then when faced with clear evidence that part of the market , and a signficant one indeed , to which he was aiming, could not make use of the ROS software. Now we are seeing on the 20 meters band, under better propagation conditions due to the so far sustained increase in solar activity, that Olivia users are facing interference from ROS users, caused by the ignorance of the Spanish inventor about amateur radio. He replied to a senior Cuban professor, a very prestigious telecommunications expert, using what could be described as foul language, an indication that confirmed that he was not only answering to my advice in such a disrespectful language. Just to add one more element... when I asked him about the possibility of writing the ROS software for LINUX users, his answer was also a clear demonstration of his ignorance about today's world. So, amigos at digital radio , my advise , and that's what I am going to do, is to alert ROS users of the possibility that the author of the software may even be attempting to use it for other purposes that are not related to amateur radio... After all, once you load a program of which you don't known the source code, into your computer, you are at the mercy of those who wrote the computer code... 73 and DX Arnie Coro CO2KK IARU Region II Area C Emergency Coordinator --- On *Sat, 3/6/10, John B. Stephensen /kd6...@comcast.net/* wrote: From: John B. Stephensen kd6...@comcast.net Subject: Re: [digitalradio] What is SS? To: digitalradio@yahoogroups.com Date: Saturday, March 6, 2010, 4:00 AM The document that the author of ROS originally published, Introduction to ROS: The Spread Spectrum, contains a good description of frequency-hopping spread-spectrum (FHSS) techniques. Section 4 describes taking a 250 Hz wide mode (MFSK16) and spreading it over 2 kHz by shifting the center frequency in a pseuorandom sequence. The receiver changes frequencies in the same sequence and the logic used to detect a special tone sequence to obtain synchronization is described in section 5. The amount of spectrum occupied increases by a factor of 8. FHSS is one way to minimize the effects of multipath spread but there are also other techniques that occupy less spectrum. Note that the author of ROS published a second doucument,ROS Technical Description , that contains elements of the original but does not mention FHSS and omits any description of how data is mapped to tones. Users comparing the original and later versions of the code haven't seen a difference in the transmitted spectrum. 73, John KD6OZH - Original Message - *From:* Rein A /mc/compose?to=rein...@ix.netcom.com *To:* digitalradio@ yahoogroups. com /mc/compose?to=digitalra...@yahoogroups.com *Sent:* Friday, March 05, 2010 19:16 UTC *Subject:* [digitalradio] What is SS? Here is a reprint that for my limited mental capacities defines the core quite well. I have asked Mike the author for some references, no lack of trust though. - - - - - -Original Message- From: n4qlb n4...@... Sent: Mar 5, 2010 1:15 PM To: ROSDIGITALMODEMGROU p...@yahoogroups. com /mc/compose?to=ROSDIGITALMODEMGROUP%40yahoogroups.com Subject: [ROSDIGITALMODEMGRO UP] Re: How do you like ROS Now? Thank You for your comments Sig. Let me explain what SS is. Spread spectrum is a method by which a bank of channels (Frequencies) are designated between a Transmitter and Receiver and are shared or (Frequency Hopped) to facilitate
Re: [digitalradio] What is SS? Senor Ros is not an honest person !
Something was telling me not to install this software, maybe it's a good thing I didn't. From: Arnaldo Coro acoro33...@yahoo.com To: digitalradio@yahoogroups.com Cc: David Sumner k...@arrl.net; Richard Moseson w...@cq-amateur-radio.com Sent: Sat, March 6, 2010 8:12:29 AM Subject: Re: [digitalradio] What is SS? Senor Ros is not an honest person ! Dear amigos: I am really concerned about the damage to the amateur radio hobby generated by a NON AMATEUR in Spain that wrote a software program for a new digital mode that very clearly to me, without any doubts , is a FHSS communications mode. I wrote e-mail messages to this person, and received some very aggressive replies from him... he even used several bad words in his messages that show that besides his very primitive knowledge of the English language _ ( he can not communicate effectively using English, as he has demonstrated many times with this very poorly written postings ) he lacks the most basic education and ethics. The topic we are dealing now is not, in my humble opinion, if ROS is or is not FHSS, it this person sent messages explaining or attempting to explain the nature of the ROS software, and then when faced with clear evidence that part of the market , and a signficant one indeed , to which he was aiming, could not make use of the ROS software. Now we are seeing on the 20 meters band, under better propagation conditions due to the so far sustained increase in solar activity, that Olivia users are facing interference from ROS users, caused by the ignorance of the Spanish inventor about amateur radio. He replied to a senior Cuban professor, a very prestigious telecommunications expert, using what could be described as foul language, an indication that confirmed that he was not only answering to my advice in such a disrespectful language. Just to add one more element... when I asked him about the possibility of writing the ROS software for LINUX users, his answer was also a clear demonstration of his ignorance about today's world. So, amigos at digital radio , my advise , and that's what I am going to do, is to alert ROS users of the possibility that the author of the software may even be attempting to use it for other purposes that are not related to amateur radio... After all, once you load a program of which you don't known the source code, into your computer, you are at the mercy of those who wrote the computer code... 73 and DX Arnie Coro CO2KK IARU Region II Area C Emergency Coordinator
Re: [digitalradio] What is SS? Senor Ros is not an honest person !
On Sat, Mar 6, 2010 at 9:12 AM, Arnaldo Coro acoro33...@yahoo.com wrote: So, amigos at digital radio , my advise , and that's what I am going to do, is to alert ROS users of the possibility that the author of the software may even be attempting to use it for other purposes that are not related to amateur radio... Yep, the dark side may be lurking. Ham transceivers are not used only by hams, so it may as well apply... Jose, CO2JA
[digitalradio] What is SS?
Hello All, I have been trying to understand from the very beginning of this circus what the real problem was and where I could read about it, from 3d independant sources. Jose the programmer has done a poor job in pinning down the core of the problem. Here is a reprint that for my limited mental capacities defines the core quite well. I have asked Mike the author for some references, no lack of trust though. In my searches on the internet I had seen pieces directing to Mike's arguments but never connected the dots. After checking with Mike N4QLB, he has been able to hear me on ROS with a couple of hundred mW, he allowed me to post it here. - -Original Message- From: n4qlb n4...@... Sent: Mar 5, 2010 1:15 PM To: rosdigitalmodemgr...@yahoogroups.com Subject: [ROSDIGITALMODEMGROUP] Re: How do you like ROS Now? Thank You for your comments Sig. Let me explain what SS is. Spread spectrum is a method by which a bank of channels (Frequencies)are designated between a Transmitter and Receiver and are shared or (Frequency Hopped) to facilitate a clear Transmisson. The Transmitter actually signals the Receiver to Hop from one frequency to another. A good example is a 900mhz digital cordless telephone or a 800Mhz digital radio truncking system. (Motorla Astro). A frequency in Ham radio consist of a 3kh wide channel. Ros does not signal a receiver to hop outside of that channel (3 Khz) therefore it is not SS and is just like anyother FSK mode used in the amatuer radio service. The ease of obtaining a License in the U.S. by people that are not technically qualified to hold one is the main culprit regarding the controversy over new modes such as ROS. I am confident that all variations of ROS are perfectly legal in the U.S. Mike N4QLB - Hope this is a positive contribution to the ongoing discussions. 73 Rein W6SZ
RE: [digitalradio] What is SS?
Mike N4QLB's claims that A frequency in Ham radio consist of a 3kh wide channel. Ros does not signal a receiver to hop outside of that channel (3 Khz) therefore it is not SS and is just like anyother FSK mode used in the amatuer radio service. are incorrect, in my opinion. Amateur radio frequencies on HF bands are not channelized at 3 khz or any other bandwidth (with the exception of 60m). I have asked Mike to cite justification for his claim on the ROS reflector that spreading a ~50 hz signal across 3 khz using classic spread spectrum techniques (e.g. a pseudo-random sequence) isn't spread spectrum. 73, Dave, AA6YQ From: digitalradio@yahoogroups.com [mailto:digitalra...@yahoogroups.com] On Behalf Of Rein A Sent: Friday, March 05, 2010 3:16 PM To: digitalradio@yahoogroups.com Subject: [digitalradio] What is SS? Hello All, I have been trying to understand from the very beginning of this circus what the real problem was and where I could read about it, from 3d independant sources. Jose the programmer has done a poor job in pinning down the core of the problem. Here is a reprint that for my limited mental capacities defines the core quite well. I have asked Mike the author for some references, no lack of trust though. In my searches on the internet I had seen pieces directing to Mike's arguments but never connected the dots. After checking with Mike N4QLB, he has been able to hear me on ROS with a couple of hundred mW, he allowed me to post it here. - -Original Message- From: n4qlb n4...@... Sent: Mar 5, 2010 1:15 PM To: rosdigitalmodemgr...@yahoogroups.com mailto:ROSDIGITALMODEMGROUP%40yahoogroups.com Subject: [ROSDIGITALMODEMGROUP] Re: How do you like ROS Now? Thank You for your comments Sig. Let me explain what SS is. Spread spectrum is a method by which a bank of channels (Frequencies)are designated between a Transmitter and Receiver and are shared or (Frequency Hopped) to facilitate a clear Transmisson. The Transmitter actually signals the Receiver to Hop from one frequency to another. A good example is a 900mhz digital cordless telephone or a 800Mhz digital radio truncking system. (Motorla Astro). A frequency in Ham radio consist of a 3kh wide channel. Ros does not signal a receiver to hop outside of that channel (3 Khz) therefore it is not SS and is just like anyother FSK mode used in the amatuer radio service. The ease of obtaining a License in the U.S. by people that are not technically qualified to hold one is the main culprit regarding the controversy over new modes such as ROS. I am confident that all variations of ROS are perfectly legal in the U.S. Mike N4QLB -- Hope this is a positive contribution to the ongoing discussions. 73 Rein W6SZ
