понедельник, 2 августа 2010 г.

PSK: INMARSAT Satellite

INMARSAT Satellite
INMARSAT AERO. OQPSK, Br-10500


Author: SergUA6
Band Width ~10500 Hz
Low Range ~750 Hz, in this example only!
Baud Rate 10500 Hz
n-Ary (PSK/MPSK) OQPSK, constellation looks as square PSK-8
Count of Carriers single mode
Carrier frequency 6079 Hz, in this example only!
ACF 500 ms
RX mode SSB

Sonograms:

pic.1 Generall view

pic.2 Baud rate
Diagrams:

pic.3 Typical characteristics of OQPSK and other half-modes.

pic.4 ACF
pic.5 View of the signal in VMW

Pictures:

pic.6 Phase constellations


INMARSAT AERO - INMARSAT is using wide enought line of different protocols. In this record, it is presumably AERO-H. The signal is very bright. All the parameteres of this signal can be easily determined.

четверг, 22 июля 2010 г.

Updating SA to the version v 6.2.0.7

Updating SA to the version v 6.2.0.7


Updating SA to the version v 6.2.0.7

It is regular updating, which includes fixing of the small errors and problems, which are not having basic value, but nevertheless demanding the decision.

new demo clip "the Review of the top ruler of tools" is added in section of demo of files. The top ruler answers basically for management of a display mode sonograms, and it is desirable to have full idea about possibilities which is in SA.

Good luck.

среда, 21 июля 2010 г.

PSK:TETRA - DMO, terminal to terminal connection

TETRA - DMO, terminal to terminal connection
Direct Mode Operation, Br-18000, pi/4 DQPSK


Author: SergUA6
Band Width ~25000-26000 Hz
Baud Rate 18000 Hz
n-Ary (PSK/MPSK) pi/4 DQPSK
Carrier frequency 15639 Hz, in this example only!
RX mode source I/Q record


Sonograms:
pic.1 Generall view

pic. Manipulation speed

pic.3 Getting of carrier frequency

Diagrams:

pic.4 Generall frame structure

Pictures:

pic.5 Constellation


TETRA - DMO, terminal to terminal connection - the mode of direct terminal (mobile stations, phones etc) connection of TETRA standard, without participation of base stations equipment.

суббота, 10 июля 2010 г.

SA update to version v 6.2.0.6

SA update to version v 6.2.0.6

We certainly cannot guarantee SA work under various emulators, including virtual machines, but nevertheless, for rather popular in LINUX environment WINE, something is already done.

In the current version, we have corrected everything that depends on us, to make SA work more or less correct in WINE.

Althought, we can't solve part of problems, because these are not SA problems, but WINE problems.

***

The format of demo files is reconsidered. Thereupon, the old format is not supported by the current version.

Support of colour scale in comments is added.

Grey colour - the comment is not actual in the present moment of time.
Yellow colour - the new comment.
Light blue (Aqua) - the comment is carried out.

There is the pause in 5 seconds after each comment. This time should be enought to read the comments.

Interruption of the demo, is reazlied throught "Space" key as before. The program supervises possibility of interruption of the demo, and in case of impossibility to stop the demo right now, it warns about it.



The previous demo clip in the new format is here. Also added small demo for check version SA. We do not plan to change format further, as in the current format, possibility of the future expansions is put in advance.

***

Possibility of virtual/analytical shift of a signal by frequency is added in OFDM module.


The sense is that absolutely exact shift on a step, which is multiple to a grid of channeles, sometimes is required atanalysis of OFDM signals. In cases of fractional values of the step, to realize it physically is hard enought, besides it demands presence of free space on/by frequency.

Virtual shift guarantees absolutely exact displacement and, because it is done purely analytically, it does not require neither signal redigitization, nor presence of free space, that is especially important if it is nessecary to shift the signal on 10-30-100 channels upwards or downwards.

Virtual shift, is actual for signals of model A, on signals of B model, this ability is blocked, as it is not necessary in
this case. There will be separate article about it.

***

In generall, providing functioning SA under WINE (in reasonable limits ofcourse), we have solved weight of small implicit problems as a whole. But nevertheless, SA is intended to work under high-grade OS, where we can guarantee something.

Good luck~

воскресенье, 4 июля 2010 г.

Scrambler: Yachta T-219

Yachta T-219
the analogue domestic synchronizable scrambler


Author: SergUA6
Band Width ~2700 Hz
Low Range ~300 Hz
Pilot tone(s): FSK-2 Synchronising sequence with frequency of manipulation 100 Hz, and spacing 150 Hz precisely on the
middle of the speech spectrum
RX mode SSB

Sonograms:

pic.1 Generall view

pic.2 Detalization of sinhro-sequence

Diagrams:
pic.3 Manipulation speed


Scrambler: Yachta T-219 - is the analogue Russian domestic synchronizable scrambler. It's principle is used by many developers of the different countries, at a speech exchange. In FSK mode Sinhro-sequence, which is located precisely on the spectrum middle is transferred. The speech spectrum breaks on two parts, above and below this sequence. All that breaks into unequal time pieces, in which limits these two speech channeles are rearranged by places and inverted. It is considered that Yachta has temporary resistence. This scrambler is widely used by military men for transfer of the operative information with limited limited term of use.

суббота, 26 июня 2010 г.

Signals Analyzer: an ability to play own demo-files is added

SA Update to version v.6.2.0.3

As it is well known there are the problems with the standard video data:

1) it is the low quality of image.
2) an extremely great volume of resulted files. On the average one minute of the image occupies about one mbyte, that limits possibilities of video clips in time, at rather mediocre quality.
3) necessity of installation of different codecs, if special format is used
4) direct dependence of volume of a material on it's quality, it is necessary to solve the question, or the big videoclip with high quality, or concerning small but with the bad quality.
5) an absense of contact with user. Even if there is perfect videoclip, in any case, it occurs somewhere, at someone's PC, on an absolutely other computer, and it does not guarantees that the same can be realized at Your PC.
6) presence of certain complexities with comments displayin on the screen.

As we can see there are a lot of minuses, although they are not so obvious at first sight. We decided to solve all these problems, or atleast to cardinally decrease sharpness of them, by providing support of own file-demo-playing in the program.

The ability to play own demo-files in SA guarantees:

1) Absolute quality of the image.
2) total absence of necessity to install additional codecs
3) all that it is necessary is only the working version of program SA.
4) minimal size of demo files.
5) four minute file has the size nearby 7 kilobyte! And it is with the absolutely hight quality of the image.
6) full contact with user, comfortable commets location.
7) approving of all actions: all actions occuring on your computer, with your OS configuration, from your's concrete version of the program as if it was done by you.

The basic innovation in this version - is support of own demo files.

All last versions SA, at installation create "Demo" folder, and now it is time to use this folder for purpose. The Demo file, which is attached to this article , does show how to work with own loader in SA. All that is necessary, it is to unpack archive into "Demo" folder and to start SA on file playing.
It should look like this:



Loading demo files into SA via menu Demo.


The panel with buttons "Play", "Exit" and field for comments will appear.

After start through "Play" button, it is necessary to watch what is occurring:-) it is not recommended to touch the mouse, as the mouse is actively used in the demo, and manual mouse moving can cause problems with demo playing.

Correct interruption of the demo is carried out through the key "Space/blank", at the first possibility the demo will be stopped. Reaction to a key is not instant, so do not be nervous and do not panic :-)

Theoretically the user can stop demo playing by random manual mouse actions, do not worry nothing terrible will happen, simply close the program, and open it again. And try do not disturb the process of demo playing further. :-)

In OFDM module, dump of images on phase planes is brought out on the separate button.

Further, we completely will cancell video clips, and we will use only own demo files.


понедельник, 21 июня 2010 г.

OFDM, COFDM: Link-11, Tadil-A, Alligator

Link-11, Tadil-A, Alligator
MIL-STD 188-203-1A, Sh-110, Br-75, Ch-14+1+Pilot, pi/4 DQPSK, k = 7/15 = 0.466(6)


Author: SergUA6
Band Width ~2400 Hz
Low Range ~500 Hz, shift is possible, recieved in SSB
Baud Rate 75 Hz in channel
n-Ary (PSK/MPSK) pi/4 DQPSK in he channel
Count of Carriers 14 frequency manipulation in the block + 1 channel + 1 pilot-tone
Step between carriers 110 Hz in the block, 550 among the block and one morePilot tone(s) 1 pilot tone ~550 Hz, shift is possible, recieved in SSB
RX mode SSB

Sonograms:
pic.1 Generall view

Diagrams:
pic.2 Graphical spectrum

Pictures:
pic.3 Structure of the short start and generall parameteres of the signal

pic.4 Constellation in the channel


Link-11, Tadil-A, Alligator - is not rare signal on the air. this signal is characteristic enough for ear. It can be easily identified, because similar stuff is hardly can be found. There are two sorts of such signal, with rather long burst as in the example and with the short one. Both sorts of this signal has identical parametres, except lengh, for LINK-11 short, it does not exceed 300 msec, and usually an order 80-100 msec. Technical speed makes 15*75*2 = 2250 bps.