Re: [digitalradio] Random data vs Spread Spectrum
Lester, I really appreciate your mannerly characterization of what I wrote as BS. :-( From the Wikipedia, a more exact definition of spread spectrum is, *Frequency-hopping spread spectrum* (*FHSS*) is a method of transmitting radio signals by rapidly switching a carrier /wiki/Carrier_wave among many frequency channels /wiki/Channel_%28communications%29, using a pseudorandom /wiki/Pseudorandom sequence known to both transmitter /wiki/Transmitter and receiver /wiki/Receiver_%28radio%29. Please post here what your own spectral analysis finds, and state if you are willing to testify to the FCC whether or not ROS is really FHSS. Thanks. 73, Skip KH6TY (No BS at this QTH!) On 7/12/2010 11:58 AM, Lester Veenstra wrote: This, as we say in the lightning fast chicken navy, the following is simply BS : ' Anyone with DigiPan or any other PSK31 program with a waterfall can verify that the frequency spreading is random and not a function of the data, which is the signature of spread-spectrum.' The use of a randomizer is not the mark of spread spectrum, but rather the mark of a well-designed modem system, where a steady state data in does not cause a lack of random transmit link data. The receiver needs a steady stream of clock transitions in order to maintain receive synchronization. The transmit waveform needs a steady stream of pseudorandom data in order to maintain a minimum carrier spectral density, than therefore reduce its potential to other users. That is to say, making your transmit waveform appear noise like (I did NOT say, under the noise), gives other modems the best chance be minimally affected. Randomness is not a differential to uniquely identify a spread spectrum modulation. However, every spread spectrum system is pseudorandom. A does not mean B, but B is A. /Lester B Veenstra MØYCM K1YCM/// les...@veenstras.com mailto:les...@veenstras.com m0...@veenstras.com mailto:m0...@veenstras.com k1...@veenstras.com mailto:k1...@veenstras.com US Postal Address: PSC 45 Box 781 APO AE 09468 USA UK Postal Address: Dawn Cottage Norwood, Harrogate HG3 1SD, UK Telephones: Office: +44-(0)1423-846-385 Home: +44-(0)1943-880-963 Guam Cell: +1-671-788-5654 UK Cell: +44-(0)7716-298-224 US Cell: +1-240-425-7335 Jamaica: +1-876-352-7504 This e-mail and any documents attached hereto contain confidential or privileged information. The information is intended to be for use only by the individual or entity to whom they are addressed. If you are not the intended recipient or the person responsible for delivering the e-mail to the intended recipient, be aware that any disclosure, copying, distribution or use of the contents of this e-mail or any documents attached hereto is prohibited. *From:* digitalradio@yahoogroups.com [mailto:digitalra...@yahoogroups.com] *On Behalf Of *KH6TY *Sent:* Monday, July 12, 2010 12:21 PM *To:* digitalradio@yahoogroups.com *Subject:* Re: [digitalradio] Moving ROS forward in the USA? Andy, I have been told by a FCC engineer, part of the evaluation group at the FCC, whom I will not name, that ROS 16 baud and 1 baud has been evaluated in the lab and is spread-spectrum and therefore illegal on HF, not only because the author first said it was spread spectrum and then changed his story. Anyone with DigiPan or any other PSK31 program with a waterfall can verify that the frequency spreading is random and not a function of the data, which is the signature of spread-spectrum. Just because someone feels it is not spread spectrum does not excuse them from following the regulations and those who do not risk the chance of FCC action against them once someone files a complaint. There is no reason for the FCC to reconsider their decision, since it is based on analysis as well as the author's declaration. What can be done is to submit a petition to the FCC to allow limited bandwidth spread spectrum on HF by showing it is not harmful to other users of the bands. The instructions for submitting a petition are available on the FCC website. Radio amateurs are responsible for following the regulations, not just interpreting them as they see fit. ROS is legal above 222 Mhz, so freely use it there if you wish. It is probably really good for EME. 73, Skip KH6TY _._,___
RE: [digitalradio] Random data vs Spread Spectrum
test. On the other hand, if the sum of the transmit symbol rates is very much larger than the user data rate, much larger than could be rationally expected by the FEC expansion, then, spread spectrum could be suspected but not proven. In the end, systems like ROS, Clover, PACKTOR-XXX, etc., where there is not full published transparency in the encoding process, are not suitable for amateur use, in my humble opinion. I am not suggesting this as a point of law, but rather as a point of good amateur practice, to be encouraged. Obviously there are some, with commercial market hopes for non-ham HF radio networks, (This is a very small and already well served market today) would not be willing to open source, but publishing the encoding details does not give away the company store. That good stuff is in the decode/demod section. - Lester B Veenstra MØYCM K1YCM mailto:les...@veenstras.com les...@veenstras.com mailto:m0...@veenstras.com m0...@veenstras.com mailto:k1...@veenstras.com k1...@veenstras.com US Postal Address: PSC 45 Box 781 APO AE 09468 USA UK Postal Address: Dawn Cottage Norwood, Harrogate HG3 1SD, UK Telephones: Office: +44-(0)1423-846-385 Home: +44-(0)1943-880-963 Guam Cell: +1-671-788-5654 UK Cell: +44-(0)7716-298-224 US Cell: +1-240-425-7335 Jamaica: +1-876-352-7504 This e-mail and any documents attached hereto contain confidential or privileged information. The information is intended to be for use only by the individual or entity to whom they are addressed. If you are not the intended recipient or the person responsible for delivering the e-mail to the intended recipient, be aware that any disclosure, copying, distribution or use of the contents of this e-mail or any documents attached hereto is prohibited. From: digitalradio@yahoogroups.com [mailto:digitalra...@yahoogroups.com] On Behalf Of KH6TY Sent: Monday, July 12, 2010 5:17 PM To: digitalradio@yahoogroups.com Subject: Re: [digitalradio] Random data vs Spread Spectrum Lester, I really appreciate your mannerly characterization of what I wrote as BS. :-( From the Wikipedia, a more exact definition of spread spectrum is, Frequency-hopping spread spectrum (FHSS) is a method of transmitting radio signals by rapidly switching a carrier among many frequency channels, using a pseudorandom sequence known to both transmitter and receiver. Please post here what your own spectral analysis finds, and state if you are willing to testify to the FCC whether or not ROS is really FHSS. Thanks. 73, Skip KH6TY (No BS at this QTH!)
Re: [digitalradio] Random data vs Spread Spectrum
Lester, The inventor has shown over and over that he is not to be trusted, and so his block diagram would not be believed either. I suggested months ago to him to just send his code in confidence to the FCC, which they would keep private, and be done with it. He replied that, arrogantly, The FCC would have to purchase the code from him. To me, that suggests that he is unwilling to disclose the code because it would prove once and for all that it was spread spectrum, and instead, he tried to bluff his way to approval, even by changing his original description of the code as spread spectrum, which obviously did not work. ROS's best advantage, IMHO, is for EME, and it is legal there for US hams for 432 and 1296 EME. I only wish it were legal on 2M also and I could use it for EME on that band. Yes, it should be open-source, and that would end the discussion, but he has (for perhaps devious or commercial) personal reasons for refusing to do so. That is just not going to happen, so let's end the discussion on that note and get on the air instead! 73, Skip KH6TY On 7/12/2010 1:14 PM, Lester Veenstra wrote: Skip: Spectral analysis cannot differentiate between a high rate FEC operating after, as it invariably must, a randomizer, and a true spread spectrum system. And a spread spectrum system does not need to employ frequency hopping. And a signal that frequency hops is not necessarily a spread spectrum signal. I refer you to the old favorite of the UK Diplomatic service, the Piccolo. As I advocated in an earlier post, the way to end this endless discussion would be for the inventor to disclose the block diagram of the various steps in his encoding/modulation system. In fact I was rash enough to suggest that IMHO, all of these systems being played with by hams, should be open sourced, so that, the end user can have some confidence in what he is using, and the state of the art can be mutually advanced. We started with this philosophy with the TTL MAINLINER-II, and continue it today with many of the DSPR systems out there, including the primary commercial company. Their disclosure does not seem to have slowed them down at all. Thanks 73 Les
RE: [digitalradio] Random data vs Spread Spectrum
Hi Skip! Well said. Now let's see how many people in the group really pay attention to what they read. From: digitalradio@yahoogroups.com [mailto:digitalra...@yahoogroups.com] On Behalf Of KH6TY Sent: Monday, July 12, 2010 1:28 PM To: digitalradio@yahoogroups.com Subject: Re: [digitalradio] Random data vs Spread Spectrum Lester, The inventor has shown over and over that he is not to be trusted, and so his block diagram would not be believed either. I suggested months ago to him to just send his code in confidence to the FCC, which they would keep private, and be done with it. He replied that, arrogantly, The FCC would have to purchase the code from him. To me, that suggests that he is unwilling to disclose the code because it would prove once and for all that it was spread spectrum, and instead, he tried to bluff his way to approval, even by changing his original description of the code as spread spectrum, which obviously did not work. ROS's best advantage, IMHO, is for EME, and it is legal there for US hams for 432 and 1296 EME. I only wish it were legal on 2M also and I could use it for EME on that band. Yes, it should be open-source, and that would end the discussion, but he has (for perhaps devious or commercial) personal reasons for refusing to do so. That is just not going to happen, so let's end the discussion on that note and get on the air instead! 73, Skip KH6TY On 7/12/2010 1:14 PM, Lester Veenstra wrote: Skip: Spectral analysis cannot differentiate between a high rate FEC operating after, as it invariably must, a randomizer, and a true spread spectrum system. And a spread spectrum system does not need to employ frequency hopping. And a signal that frequency hops is not necessarily a spread spectrum signal. I refer you to the old favorite of the UK Diplomatic service, the Piccolo. As I advocated in an earlier post, the way to end this endless discussion would be for the inventor to disclose the block diagram of the various steps in his encoding/modulation system. In fact I was rash enough to suggest that IMHO, all of these systems being played with by hams, should be open sourced, so that, the end user can have some confidence in what he is using, and the state of the art can be mutually advanced. We started with this philosophy with the TTL MAINLINER-II, and continue it today with many of the DSPR systems out there, including the primary commercial company. Their disclosure does not seem to have slowed them down at all. Thanks 73 Les
Re: [digitalradio] Random data vs Spread Spectrum
Why do you persist in getting the FCC involved? You are potentially damaging the hobby as a whole. If one is qualified to hold a license the FCC presumes ones ability to determine what operations are legal. On 7/12/10 1:28 PM, KH6TY kh...@comcast.net wrote: Lester, The inventor has shown over and over that he is not to be trusted, and so his block diagram would not be believed either. I suggested months ago to him to just send his code in confidence to the FCC, which they would keep private, and be done with it. He replied that, arrogantly, The FCC would have to purchase the code from him. To me, that suggests that he is unwilling to disclose the code because it would prove once and for all that it was spread spectrum, and instead, he tried to bluff his way to approval, even by changing his original description of the code as spread spectrum, which obviously did not work. ROS's best advantage, IMHO, is for EME, and it is legal there for US hams for 432 and 1296 EME. I only wish it were legal on 2M also and I could use it for EME on that band. Yes, it should be open-source, and that would end the discussion, but he has (for perhaps devious or commercial) personal reasons for refusing to do so. That is just not going to happen, so let's end the discussion on that note and get on the air instead! 73, Skip KH6TY On 7/12/2010 1:14 PM, Lester Veenstra wrote: Skip: Spectral analysis cannot differentiate between a high rate FEC operating after, as it invariably must, a randomizer, and a true spread spectrum system. And a spread spectrum system does not need to employ frequency hopping. And a signal that ³frequency hops² is not necessarily a spread spectrum signal. I refer you to the old favorite of the UK Diplomatic service, the Piccolo. As I advocated in an earlier post, the way to end this endless discussion would be for the ³inventor² to disclose the block diagram of the various steps in his encoding/modulation system. In fact I was rash enough to suggest that IMHO, all of these systems being played with by hams, should be open sourced, so that, the end user can have some confidence in what he is using, and the state of the art can be mutually advanced. We started with this philosophy with the TTL MAINLINER-II, and continue it today with many of the DSPR systems out there, including the primary commercial company. Their disclosure does not seem to have slowed them down at all. Thanks 73 Les
Re: [digitalradio] Random data vs Spread Spectrum
Hi W2XJ, Could you tell me please ( I am believe to be the only person in the group of 4000 seriously interested in this subject as a potential user ) the exact definition of SS in this connection. Open domain references available to me as a non menber of IEEE and the rest. frequency hopping published protocol in public domain being available to FCC or NSA et al to read transmissions. What all else goes into this. It is called by FCC illegal but they do not provide tthe test criteria for me to make that descision. I think I can do: from SS is: -1-, -2-,-3- ask is Ros -1- or not? is Ros -2- ,, etc. It has the same or slightly smaller than SSB does not do it I think I like to read or be able to search -1- , -2- , and so on from a reliable source not private, agenda based opinions. I went yesterday through all emails on the ros modem group and got certain impressions from doing this. I hope you read this and engage, here or in private. === Given the statement via ARRL outlet. What happens if FCC ask me hey I tell them well I did the analysis, found this and the other party tells me sorry sir you are wrong and you violated section this and that? even I were to ask, why please and they say, we told you it was illegal! 73 Rein W6SZ -Original Message- From: W2XJ w...@w2xj.net Sent: Jul 12, 2010 5:52 PM To: digitalradio@yahoogroups.com Subject: Re: [digitalradio] Random data vs Spread Spectrum Why do you persist in getting the FCC involved? You are potentially damaging the hobby as a whole. If one is qualified to hold a license the FCC presumes ones ability to determine what operations are legal. On 7/12/10 1:28 PM, KH6TY kh...@comcast.net wrote: Lester, The inventor has shown over and over that he is not to be trusted, and so his block diagram would not be believed either. I suggested months ago to him to just send his code in confidence to the FCC, which they would keep private, and be done with it. He replied that, arrogantly, The FCC would have to purchase the code from him. To me, that suggests that he is unwilling to disclose the code because it would prove once and for all that it was spread spectrum, and instead, he tried to bluff his way to approval, even by changing his original description of the code as spread spectrum, which obviously did not work. ROS's best advantage, IMHO, is for EME, and it is legal there for US hams for 432 and 1296 EME. I only wish it were legal on 2M also and I could use it for EME on that band. Yes, it should be open-source, and that would end the discussion, but he has (for perhaps devious or commercial) personal reasons for refusing to do so. That is just not going to happen, so let's end the discussion on that note and get on the air instead! 73, Skip KH6TY On 7/12/2010 1:14 PM, Lester Veenstra wrote: Skip: Spectral analysis cannot differentiate between a high rate FEC operating after, as it invariably must, a randomizer, and a true spread spectrum system. And a spread spectrum system does not need to employ frequency hopping. And a signal that ³frequency hops² is not necessarily a spread spectrum signal. I refer you to the old favorite of the UK Diplomatic service, the Piccolo. As I advocated in an earlier post, the way to end this endless discussion would be for the ³inventor² to disclose the block diagram of the various steps in his encoding/modulation system. In fact I was rash enough to suggest that IMHO, all of these systems being played with by hams, should be open sourced, so that, the end user can have some confidence in what he is using, and the state of the art can be mutually advanced. We started with this philosophy with the TTL MAINLINER-II, and continue it today with many of the DSPR systems out there, including the primary commercial company. Their disclosure does not seem to have slowed them down at all. Thanks 73 Les
Re: [digitalradio] Random data vs Spread Spectrum
It was not my idea. The author wanted the FCC to say it was not spread spectrum. Unfortunately for all of us in the US, it is spread spectrum, and the FCC rules do not allow that below 222 MHz. I am not potentially damaging the hobby as a whole, just posting what I know. Go ahead and use ROS if you think you will be legal! You will do more damage to the hobby than anyone who refuses to use it, by flaunting the regulations. 73, Skip KH6TY. On 7/12/2010 1:52 PM, W2XJ wrote: Why do you persist in getting the FCC involved? You are potentially damaging the hobby as a whole. If one is qualified to hold a license the FCC presumes ones ability to determine what operations are legal. On 7/12/10 1:28 PM, KH6TY kh...@comcast.net kh...@comcast.net wrote: Lester, The inventor has shown over and over that he is not to be trusted, and so his block diagram would not be believed either. I suggested months ago to him to just send his code in confidence to the FCC, which they would keep private, and be done with it. He replied that, arrogantly, The FCC would have to purchase the code from him. To me, that suggests that he is unwilling to disclose the code because it would prove once and for all that it was spread spectrum, and instead, he tried to bluff his way to approval, even by changing his original description of the code as spread spectrum, which obviously did not work. ROS's best advantage, IMHO, is for EME, and it is legal there for US hams for 432 and 1296 EME. I only wish it were legal on 2M also and I could use it for EME on that band. Yes, it should be open-source, and that would end the discussion, but he has (for perhaps devious or commercial) personal reasons for refusing to do so. That is just not going to happen, so let's end the discussion on that note and get on the air instead! 73, Skip KH6TY On 7/12/2010 1:14 PM, Lester Veenstra wrote: Skip: Spectral analysis cannot differentiate between a high rate FEC operating after, as it invariably must, a randomizer, and a true spread spectrum system. And a spread spectrum system does not need to employ frequency hopping. And a signal that frequency hops is not necessarily a spread spectrum signal. I refer you to the old favorite of the UK Diplomatic service, the Piccolo. As I advocated in an earlier post, the way to end this endless discussion would be for the inventor to disclose the block diagram of the various steps in his encoding/modulation system. In fact I was rash enough to suggest that IMHO, all of these systems being played with by hams, should be open sourced, so that, the end user can have some confidence in what he is using, and the state of the art can be mutually advanced. We started with this philosophy with the TTL MAINLINER-II, and continue it today with many of the DSPR systems out there, including the primary commercial company. Their disclosure does not seem to have slowed them down at all. Thanks 73 Les
RE: [digitalradio] Random data vs Spread Spectrum
) gain in interference rejection. Most HF bands do not have the bandwidth available for any but the very low rate user rates, hence the banishment to UHF. The other gotcha is that every signal in the spread bandwidth gets “despread” to contribute to the despread noise floor. Consider the previous example. If, within the spread bandwidth there was another signal, not within the 10 KHz bandwidth of the desired signal, but 20 dB higher in power, the result would be at the despread point, you are now back to 0 dB S/N. Sane result for ten carrier only 10 dB stronger. Lots of strong carriers that you the narrow band carrier are trying to squeeze through sure sounds like a description of a typical HF band. Instead of spread spectrum, what is the much more powerful technique in the real HP world is source code and modulation code so that you transmit your encoded information as energy over a number of frequencies (Frequency Diversity), simultaneously over a number of time slots, both coding with a powerful FEC code, such as rate ½ or 1/3, so that there is a high probability of recovering the information, un corrupted, from a channel with high interference for short periods of time over narrow, and with frequency selective fading (QSB) also in a narrow band instantaneous occurrence. The optimum solution is to use the available energy divided into multiple small carriers on a range of adjacent frequencies or in a single hopping carrier over a similar bandwidth, coded to provide FEC and time diversity so that if a hops information is lost when it gets stepped on by QRM, but recovered when multiple other hops are received and the result decoded. Any data transmission system will increase the occupied bandwidth in some fashion, as a function of the encoding steps used to develop the modulated waveform. This increase in bandwidth is used to improve the end to end performance, i.e., to improve the Eb/No vs BER curve. This FEC/Coding/Modulation choice is optimized by the ingenuity of the designer, but limited by the allowed (regulated) bandwidth for the situation. There is a point of diminishing returns in all of this. You must be able to maintain synchronization of frequency and bit timing from one end to the other end of a link in order to keep the FEC decode process working. This becomes harder and harder to do when the power spectra density becomes close to the power spectral density of the noise (QRNQRM). Further on multi hop HF links and on moon bounce, you get multipath effects that make both the received frequency and timing change, in some cases changing faster than the transmit symbol rate. This makes recover of the right bit in the right time location a problem. So, if bits are added to the transmit waveform that are not performing a function of helping to re-create an error free replication of the input data, it meets my test as spread spectrum. If the symbols in the transmit waveform cannot be predicted by the previous sequence of bits over time at the input, it also would meet my test as spread spectrum. To reiterate on this point, just because the symbols of the transmit waveform are changing during an unchanging input, does not imply spread spectrum. Instead, they may well be the result of a defined randomizer process followed by multiple layers of FEC and modulation coding. Excuse please my long winded response. If my intelligence has descended into the noise floor at some point or points, please nail me to the wall and I will try to clarify. Lester B Veenstra MØYCM K1YCM mailto:les...@veenstras.com les...@veenstras.com mailto:m0...@veenstras.com m0...@veenstras.com mailto:k1...@veenstras.com k1...@veenstras.com US Postal Address: PSC 45 Box 781 APO AE 09468 USA UK Postal Address: Dawn Cottage Norwood, Harrogate HG3 1SD, UK Telephones: Office: +44-(0)1423-846-385 Home: +44-(0)1943-880-963 Guam Cell: +1-671-788-5654 UK Cell: +44-(0)7716-298-224 US Cell: +1-240-425-7335 Jamaica: +1-876-352-7504 This e-mail and any documents attached hereto contain confidential or privileged information. The information is intended to be for use only by the individual or entity to whom they are addressed. If you are not the intended recipient or the person responsible for delivering the e-mail to the intended recipient, be aware that any disclosure, copying, distribution or use of the contents of this e-mail or any documents attached hereto is prohibited. From: digitalradio@yahoogroups.com [mailto:digitalra...@yahoogroups.com] On Behalf Of rein...@ix.netcom.com Sent: Monday, July 12, 2010 8:33 PM To: digitalradio@yahoogroups.com Subject: Re: [digitalradio] Random data vs Spread Spectrum Hi W2XJ, Could you tell me please ( I am believe to be the only person in the group of 4000 seriously interested in this subject as a potential user ) the exact definition of SS
