MPSK: QMAC signal.

QMAC

MPSK, 30-th Ch, Br~43.1, Sh~53-54, + 1 Ch as synchro

Author: SergUA6

Band Width 2000 Hz

Low Range ~400 Hz, shift is possible.

Baud Rate ~43.1 Hz

n-Ary (PSK/MPSK) PSK-8(pi/4 DQPSK)

Count of Carriers 20+10+1

Step between carriers ~53-54 Hz

RX mode SSB

Here is the record of this signal.

Sonograms:

pic.1 General view

pic.2 Speed in the channel

pic.3 Detalization

Diagrams:

pic.4 Phase constellation in the channel

QMAC - it is well known enough bar of HF equipment. There is an example of it's work in the record. The signal is multichannel, with obvious separating of channels. It is not classical OFDM signal, although, at first view it looks similar to OFDM. The signal has bright enough features. The record is made in mp3 format initially, so the quality of the record is so-so, it could be better.

Signals Analyzer: 2 license keys for the price of 1.

I guess this information will be usefull : everyone is able to get SA two license keys for the price of one.

Since Jule(2009), after purchasing the first SA license key, we send the second SA license key free of charge. Since the most part of users, as a rule, have two working computers.

I'v decided publish this information in my blog, because still most of people do not know about this ability to get 2 keys for the price of 1.

It is official information from our official site.

Sincerely yours, Maria and MSM Group.

Signals Analyzer: SA - OFDM module detailed tutorial. Part I.

SA - OFDM module detailed tutorial. Part I.

This tutorial is intented to help with solving difficult enough tasks of OFDM analysis.

The purpose of this tutorial - is to show what is possible to learn/understand/define with the help of current implementation of SA OFDM module and small "magic triangle":).

Click here to read full OFDM module SA tutorial by MSM Group.

From this SA OFDM module tutroial you will know:

• how to define the magic OFDM triangle
• how to recognize the right one triangle, in case, when there are several triangles in the signal
• when triangle can be negative and what does it mean
• what the correct "magic triangle" should look like
• specifics of "behavour" of the correct "magic OFDM triangle"
• and more interesting and usefull features for effective analysis of OFDM signals with help of SA OFDM module.

Soon the second part of OFDM module tutorial will appear.

Yours sincerely, Maria and MSM Group.

The unqiue OFDM module is added: Signals Analyzer updated. version 6.1.0.0/1.

Signals Analyzer new updated version 6.1.0.0/1.

In SA version 6.1.0.0/1 OFDM module is added. New SA OFDM module is the unqiue tool, which do not have analogues.

The detailed description of OFDM module is available in our site. Click here to read detailed OFDM module tutorial.

This tutorial is "must read", it is short, but infromative description of princples of OFDM analysis and principles of work with SA OFDM module.

Everyday more OFDM signals are appearing, and they are always problematical for the analysis. SA OFDM Module is intented to help and greatly simplify the analysis of OFDM signals.

From our description of version 6.1.0.0/0 You will know:

• basics and princples of OFDM analysis
• structure of OFDM signals
• "Magic traingle" as the sign of OFDM presence
• how to recognize "Magic triangle"
• easy steps of how to use OFDM module
• the results of SA OFDM module work.

Current implementation of SA OFDM module is only the first step in this direction. Further we will expand and develop OFDM module to receiving of constellation of the separate channel, to compensation of inaccuracies of sampling rate and displacement by frequency, and if it ill be possible, to OFDM module full automation of putting to rights parameters of record.

We are also planning to write very detailed and usefull article about work in SA OFDM Module, because possibilities of SA OFDM module are great, and some part of very vexed questions(which are often discussed on forums), can be easily enough solved with SA OFDM module help.

Sincerely, Maria and MSM Group.

What is signals analysis? And why the signals must be analyzed?

What is signals analysis? What is it nessecary for? Why is it not possible to use decoders without analysis of the signals?

Author: SergUa6 and other MSM Group members.

We receive many letters with such questions, despite the fact, that the answers to these questions are stated in number of our articles, we have decided to make this short, but informative article. Okay, let's begin from start.

Everyone who has receiver heard not clear sounds and strange signals, and each time there is the question what is it? Only extremely small amount of people can exactly identify these signals and sounds for sure. While most number of people still suppose, that the only one way to identify the signals it is their ears. This is an absolute error.

Let's consider "analysis by ear" on the real examples and situations.

Examples of What is impossible to do by "ear-analysis":

• to distinguish OFDM with 20th channels from OFDM with 18 channels
• to hear the difference between OFDM with manipulation speed 50 and 45
• to differ PSK from QAM
• to distinguish PSK-8 from PSK-4
• to hear the difference between GFSK from MSK
• to distinguish FSK with speed 1200 from PSK with speed 1200
• to distinguish MFSK-32 from MSFSK-30
• ear can't exactly define that frequency spacing is 110 for example, instead of 100
• You can't distinguish MFSK-64 from MFSK-60 by ear

I can endlessly countine this list of the real and widespread situations ,where "ear-analysis " fails and simply doesn't work.

Ofcourse it is possible to distinguish CW from RTTY by ear, same as we can differ male and female voice and etc. But it is better to close the question about abilities of ear-analysis. With each day there are more and more digital signals and protocols are appearing, already for today there are more then thoudands types of them, and all that can't be identified and analyzed by "ear-analysis". Let's leave for ears things which are ment for them: music, speech, CW.

We were surprised by the fact that there are people, who believe in "ear-analysis", mostly that part of people believes that there are only two types of the signals: CW and RTTY. Thus, "ear-analysist" name everything what is not getting under these two cathegories as "digit" type.

The main function of the signals analysis - is exact and precise definition of parametres of a signal, such as: speed, sort of manipulation and much more. That allows to identify the signal absolutely precisely and authentically.

pic.1 Function of Signals Analysis

The picture 1 shows the purposes and the place of analysis. To us it is well-known that many people ignore the analysis basically, because they believe that decoders "will understand" and decode any signal and even unknown sound. Probably many people from those who are reading this article, got into situation when the decoder program produces random set of digits or characters. And there are no ways to understand what are the reasons for it, and how much authentic is this set of characters and digits or is it simply random trash?

I don't think that i'm opening the big secret: but all decoders work only with that type of signals, for which these decoders were specially created. In case if the signal has another parameters, like different speed, or another modulation, or any other parameteres from the expected ones, then even best decoder can't realize it's functions and don't decode anything.

Ofcourse the good decoder program has customised parametres, but how it is possible to expose/specify the parametres, if they are not defined precisely or not even known at all? And where is a guarantee, what you try to decode some correctly identified signal, instead of absolutely another?

The good analyzer will help with solution of all these problems:

• with precise definition of parametres of the signal
• with identification of the signal
• with a choice of the suitable decoder, for any signal which you have accepted/have written.

pic.2

As it is well-visible from picture 2: it is impossible to decode any sound and signal without Signals Analysis.

The analysis itself is not so hard as it may seem at first look, but it requires training and learning as any other professional or hobby sphere. It is same situation when : as soon as you learn how to read books at school - you open another interesting world, while illiterate person do not even know about existence of such world.

But if to meet the illiterate person today is uncommon thing, to meet "ear-analyst" is the very usual situation, althought "ear-analysis" is very similar to illiteracy:)

MSM Group is applying all best efforts and doing all possible and also impossible, to help everyone who wants to become engaged into signals analysis and develop their skills in that direction.

Good luck!

FSK: Russian native Airforce "Chayka" - telecode "Chayka"

Russian Airforce "Chayka" - telecode "Chayka"

Command/short message system, crypto, FSK-2.

• An example of the signal with frequency manipulation in 75Hz (this record was send us by PassTR)
• An example of the signal with frequency manipulation in 150Hz (this record was send us by Skif585)

Author: SergUA6

Band Width ~ 600 Hz

Low Range ~ 500 Hz, shift is possible, recieveing in SSB

Baud Rate 75, 150, 300, 1200 Hz

Count of Carriers 2 well visible frequency of manipulation on speed in 75Hz, but on 150-300Hz it will be problematic

Step between carriers 500 Hz

RX mode SSB

Sonograms:

pic.1 General view

pic.2 Speed of manipulation

pic.3 The repeated fragment

Diagrams:

pic.1 The exact frequency spacing

Russian Airforce "Chayka" - One of native Russian systems (equipment "Chayka") of interactions of military air forces and land stations.

It is old enough system, is probably still used today, because the transmission is encrypted and it is hard enought to identify it with high level of reliability.

An implicit signs of this system: the preamble presence, an alternation of tones with frequency of manipulation in the beginning, and also rare enough rating of frequencies 500 Hz. There is well visible presence of the repeating part, which is aldo vegin from the short preamble, on the third sonogram . Speed is 1200, it is most likely used on VHF a range (usual practice), other speeds are used for connection on HF. Sea-gull is the English translation for Russian word "Chayka:'.

FSK: "AKULA" Russian NAVY.

"AKULA" Russian NAVY.

FSK-2, Shift-1000, Br-500

Author: SergUA6

Band Width ~1800 Hz

Low Range ~500-600 Hz, shift is possible, recieving in SSB

Baud Rate 500 Hz

Count of Carriers 2

Step between carriers 1000 Hz

RX mode SSB

Here is AKULA Russian Navy signal

Sonograms:

pic.1

pic.2

Diagrams:

pic.3

Russian CIS NAVY "AKULA" - The signal of Russian communication system "AKULA". It is applied in the Navy. It is old enough system, the transfer is enciphered.

The features of this system: the preamble begins with doubled "plus" by duration, the rating/spacing is precisely equal to the doubled speed of manipulation, and the manipulation is without phase rupture. SHARK is translation for Russian word "AKULA".

SA: Automatical Parameters Detection. Update to Version 6.0.7.2

Signals Ananlyzer: Autodetection of Parameters.

Version 6.0.7.2

In version 6.0.7.2 function ADP - Autodetection of Parameters of a signal is announced . We added this function for the several reasons. In the first, it is well-known to that presence of this function will strongly please and attract some part of users:-). In the second, the task is extremely difficult and therefore is very interesting, well and in the third, there is the big desire to release an analyst from routine operations at the analysis.

At once should tell that the automation will not substitute and cannot make a competition to the skilled analyst. In this sense it is not necessary to create the big illusions about automation, there always will be the signals, which will demand an absolutely not standard approach and which will stump any automation. As well, since we only started development in the field of autodetection of parametres, it is not necessary to expect at once very amazing results, it is very serious sphere, and we have lot of work in this sphere. We have decided to start with small: From definition of speed of manipulation, as the speed of manipulation is one of the key moments in analysis.

Current implementation of ADP, works primitively enough, at the level of an average-skilled analyst, and solves only tasks of definition of the speed of manipulation. Further we plan to well expand quantity of auto-detected parametres and the reliability of definition. With this start implementation of ADP we designate one of main directions, in which we are going to work and develop SA.

It is simple enough to launch ADP: you only need select signal's area with horizontal and vertical markers. Horizontal markers set/limit the signal's bar by frequency, and vertical markers set the time-segment.

Certainly the interval of time should not be very short and or too long. In the first case it is not possible to receive exact value of frequency of manipulation or even impossible to measure it at all, in the second case too much time can be demanded. Standardly it is desirable to have the time-segment not less than 1 second and not more than 10-20sec, but depends of sampling rate and features of the signal, there is a lot of nuances.

Examples:

Some minor problems detected by users and beta-testers are solved. We would like to express much thanks for it to users and beta-testers.

I would like to remind once again, that ADP don't give 100% guarantees yet. Alhought ADP alghorytm successfully solves it's tasks in most cases on rather simple signals.

Good luck!

Signal : Clover 2000

Clover 2000
Clover 16p4a, mixed PSK-16 manipulation and four-lever AM at the same time

Author: SergUA6 6.0
Band Width ~ 2000 Hz
Low Range 500 Hz
Baud Rate 62.5 Гц, in the channel
n-Ary (PSK/MPSK) PSK-16
Count of Carriers 8 spectral bands with not crossed spectrum
Step between carriers 250 Hz between carriers of the channels
RX mode SSB

The very qualitative sample of Clover 2000

Sonograms:

pic.1 General view

Diagrams:

pic.2 Graphical spectrum

Pictures:

pic.3 Phase constellation

pic.4 Crossings in constellation

This signal is from Clover family of signals. It is rare enough signal on the air. For definition of parametres of the channel, it it is necessary preliminary to select it. The constellaions, which are represented in the description, concerned to the lower channel by the spectrum.

Usage of the mixed modulation, allows to increase speed in the channel, for this variant it turns out (if I'm not mistaken) 6*62.5=375 bit per second on the channel, the common speed is 3000 bps. That is not bad characteristic, at the 2000Hz band on HF.

UDXF Forum discussion:Unidentified signal on 8600.9kHz USB (France)‏

Unidentified signal on 8600.9kHz USB (France)‏.

http://f1jek.ns5-wistee.fr/mp3/8600.9khz.mp3
http://f1jek.ns5-wistee.fr/mp3/8600.9khz.mp3

After analysis we identifed that signal. It is Globe Wireless OFDM Waveform.

The quantity of channels is well visible from the picture, there are 16 channeles. Not each analyzer is able to show it on such Signals. The matter is that GW has the very short CP and short enough body of the signal, it does not allow to distinguish channels by usual analyzers. Manipulation mode in the channels for GW is standardly PSK-4 (QPSK). Speed of manipulation approximately is 55-56 Hz.

The record is in mp3, althought *.wav format is the best for analysis. For the ones who want to know more about how to make a good record for analysis i post the link on our short article with easy steps "Record for the following analysis".

It will be usefull to read.

Thanks to UDXF forum for interesting discussion and UDXF members for the signals.