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MultiPSK 4.32alt

Clock 1.11.1

Multicom 1.1

Multidem 2.5.1

Modes supported by Multipsk:

  • Phase Shift Keying modes:
    • BPSK: BPSK31-63-125-250 / CHIP (64/128) / PSK10 / PSKFEC31 / PSKAM10-31-50
    • BPSK with SSTV: PSK63 F - PSK220F + DIGISSTV "Run"
    • QPSK: QPSK31-63-125-250
    • 8PSK: VDL2
    • MPSK: MT63
    • PACKET BPSK1200-250-63-31 + APRS+ DIGISSTV "Run"
    • MIL-STD-188-110A - 4285
    • HFDL
    • EPIRB-ELT-PLB beacons
    • ARGOS (beacons/satellites)
    • AUTEX
    • ORBCOMM
  • On-Off Keying Modes: CW / CCW-OOK / CCW-FSK / QRSS
  • Amplitude modulation mode: APT faxes (NOAA satellites)
  • Frequency Shift Keying modes:
    • PACKET: 110-300-1200 bauds + APRS+ DIGISSTV "Run"
    • PACTOR 1 / AMTOR FEC-Navtex / AMTOR ARQ / SITOR A
    • ASCII / RTTY 45-50-75-100-110-150-200 / SYNOP + SHIP / IEC 870-5
    • 1382 / BIIS / GMDSS DSC / ATIS / ACARS (VHF) / DGPS / NWR SAME / ARQ-E / ARQ-E3
  • Multi Frequency Shift Keying modes:
    • MFSK8 / MFSK16/32/64 (+SSTV)
    • OLIVIA / Contestia / RTTYM / VOICE
    • THROB/THROBX
    • DominoF / DominoEX / THOR
    • PAX / PAX2
    • Automatic Link Establishment (see http://www.hflink.com) MIL-STD-188-141A+
      ARQ FAE / ALE400 + ARQ FAE
    • DTMF, SELCAL
    • JT65 (A B and C)
    • LENTUS
    • COQUELET
  • Base band modes: POCSAG, AIS, Packet 9600 bauds (G3RUH)
  • Hellschreiber modes: FELD HELL / FM HELL(105-245) / PSK HELL / HELL 80
  • Graphic modes: HF FAX / SSTV / PSK SSTV modes (mentioned above) / MFSK16 SSTV (mentioned above)
  • PPM (by positioned pulses) modes: mode S (ADS-B included)
  • DSP modes: Filters / Analysis / Binaural CW reception
  • RTTY, CW, BPSK31, BPSK63 and PSKFEC31 Panoramics
  • Identifiers: Video ID / RS ID / Call ID
  • TCP/IP digital modem
  • Integered SdR demodulator/modulator

The main improvements of MULTIPSK 4.32 are the following:

1) New mode AERO (RX)

The Inmarsat "ClassicAero" channel P service consists of downlink messages from geostationary satellites (Inmarsat 3F1, 3F2, 3F3, 3F4, 4F1 and 4AF4) to planes. These messages are transmitted from ground stations (GES) to planes (AES) (but not AES to GES), according to the "Satcom ACARS" system protocol (with "SatCom" for "Satellite Communication" and "ACARS" for "Aircraft Communication Addressing and Reporting System"). ACARS is a data protocol defined by ARINC (Aeronautical Radio, Inc). ACARS is also used in VHF ("ACARS" mode on Multipsk).

The Satcom ACARS system is used in preference to standard VHF ACARS when planes are beyond VHF range or if VHF channels are congested, particularly in Europe. The frequencies used are 1545.0 to 1545.2 MHz for 600 and 1200 bauds transmissions and 1546.0 to 1546.11 MHz for 10500 bauds transmissions.

The Inmarsat AERO satellites transmit a great number of management frames relative to transmission and satellites link. They are decoded but encrypted. Reversely, several messages are text relative to weather reports (decoded by Multipsk), flight plans, etc.. These are the only messages really interesting.

For Hams and SWL, a signal can be received:

· either from the discriminator output of a classical UHF FM receiver via a direct connection to the PC sound card (only for 600 and 1200 bauds modes),

· or, possibly, from the UHF FM receiver speaker through a simple direct connection to the PC sound card (only for 600 and 1200 bauds modes),

· or with a SdR receiver (FunCube Dongle, RTL SDR,...) and directly demodulated (in FM for the 600 and 1200 bauds modes and PSK for the 10500 bauds mode) by Multipsk.

Here it will be found a guide to receive and decode AERO transmissions with Multipsk: http://f6cte.free.fr/AERO_easy_with_Multipsk.pdf

This mode is available for licencied copies, only (otherwise, the decoding is stopped after 5 minutes).

See general specifications further on.

2) SDR spectrum analyzer on 250 KHz ("Spectrum SdR" button in the upper left part of the RX/TX window)

This application permits to make acquisition of I/Q signals coming from a SdR receiver (RTL/SDR keys only) and to display them under the form of a E = f(F) spectrum with "E" gain in the scale 0 to 1 (or expressed in dB) and "F" the frequency in KHz. The gain corresponding to 1 corresponds to the largest sinusoid being able to be digitalized by the SdR receiver.
A "waterfall" permits, besides, to display the spectrum versus the time, but without large precision.
The SdR receiver frequency (RTL/SDR key) can be directly tuned with a mouse click, either on the spectrum or on the waterfall.

This function is useful to have a general view of a wide band of frequencies (250 KHz). For example, to see the low AERO band (1545.0 to 1545.2 MHz), the receiver will be tuned (with the Multipsk "Transceiver" function) in the middle of this band, so 1545.1 MHz.

3) Other improvements

· Parameters management (in the "Parameters" box of the "Configuration" screen)

The program works with a lot of parameters which can be modified by the user. These parameters are mainly stored in the CONFPSER.SER file but not only. Some management tools are proposed to the user.

The main possibility is to record all the parameters for a given configuration ("FAX", "VDL2", for example) and to come back, later, to this configuration, with just several clicks. The configurations are stored in the "CONFIGURATIONS" sub-directory of the MULTIPSK folder, as for example: C:\MULTIPSK\CONFIGURATIONS\FAX

· Weather (METAR/SPECI/TAF) uplink ACARS messages decoded (on basic specifications only) in the AERO/HFDL/ACARS/VDL2 modes

· New sampling frequency of 1 MHz for all modes except ADSB, when a RTL-SDR key is used, the previous 250 KHz sampling frequency introducing noise in all bands

Note about TLE files: if you use the "Satellites" option, don't forget to download

(with the "Downloading" button) the 5 recent TLE files (amateur.txt, argos.txt, orbcomm.txt, stations.txt, weather.txt).

Note about translation of Multipsk.exe and Clock .exe: the 4.31.4 version of Multipsk has been completly translated to Spanish by Joachin (EA4ZB), from French. The translation file is on my Web site (http://f6cte.free.fr/Translation_files.htm).

Description of the Aero mode channel P (UHF, L band)

Baud rate: 600, 1200 or 10500 symbols/second.

Modulation:

· For 600 and 1200 bauds transmissions, it is used the Aviation-BPSK modulation, called also SDPSK (Symmetrical Differential Phase Shift Keying), i.e. a "0" is transmitted with a -90 shift of the carrier phase whereas the "1" is transmitted with a 90 shift. The transmission could be demodulated in PSK, but it is more simple (even if the minimum Signal to Noise ratio is not so good) to demodulate in FM. This because in PSK, the carrier phase must be followed and locked whereas in FM it is not necessary (the baseband signal is directly supplied). Moreover, for the user, the tuning needs less accuracy.

· For 10500 bauds transmissions, it is used the Aviation-QPSK modulation which is a technique which maps a "0" into a 0 degree angle and "1" into a 180 degrees angle or a "0" into a 90 degrees angle and "1" into a 270 degrees angle, alterning between the two options on successive bits. In this case, even if FM could be used, it is appropriate (an error and not PSK leadin to series of errors). So only PSK demodulation is used.

Shape of pulse: specified by two templates (upper and lower bounds) for A-BPSK and A-QPSK, to limit spectral occupancy. They seem to correspond to Root Raised Cosine filters.

Bandwidth: 800 Hz in 600 bauds, 1600 Hz in 1200 bauds and about 8000 Hz in 10500 bauds.

Demodulation: FM (600 or 1200 bauds) or PSK (600, 1200 or 10500 bauds)

Bit synchronization: automatic using the signal

Data synchronization: an unique word of 32 bits in A-BPSK and 64 bits in A-QPSK.

Correction code: no, but a CCITT checksum permits to validate each message of 12 bytes

Convolution code: FEC R=1/2, k=7

Interleaving: yes

Scrambling: yes

Lowest S/N: about +1 dB at 600 bauds, +4 dB at 1200 bauds and +14 dB at 10500 bauds.

 

 

The main improvement of Multipsk 4.31.4 is an addition of a SDR TCP/IP interface.

Main goal

This new version proposes a SDR TCP/IP interface able to interface SdR receivers, as the direct or EXTIO interfaces. It is simple and can be used for an exchange between:
* a client program (Multipsk, for example),
* a SdR (local or remote) able to transmit IQ 16 bits samples, at a sampling rate of 48000 Hz.

For developers, it is proposed programs permitting a complete simulation of a server and a client (see below).

This version of Multipsk managed a basic application, i.e. the mandatory part of the version 0 of the protocol:

* the default sampling frequency (48000 Hz),

* the default hardware type managed: 3 (16 bits, IQ),

* the mandatory procedures (Pversion, HWMPcapa, InitHWMP, Set_HWLO, Received, Bug_on_P).

The hardware type 4 (with only a frequency control, data coming from a specific sound card, as for the Funcube) is also managed by Multipsk.

It will be possible to manage either a SDR server located in the same PC or a remote SDR server. In other words, it would be possible to decode transmissions from your receiver located in an other place, if autorized in your country.

Typical working for the user

In the standard option, the SDR server file must be in the same directory as Multipsk. As an example, it is proposed, for a test, a simulation of server SDR_TCP_IP_TEST.exe. This pseudo-server generates and sends an IQ signal at 6000 Hz (square wave).

After having started Multipsk, push on the pink “SdR TCP/IP” button of the “I/Q interfaces for SdR transceivers” panel. Push on the “Connection” button. Once the connection done, the number after “N=” (number of data) increases. Close this TCP/IP window and push on “RX/TX screen”, as usual. The 6000 Hz signal will be visible in the SdR waterfall.

Extract from the manual:
……………………………………………………………………………….

- If the "SDR TCP/IP" button is pushed, the SdR interface is forced.

Indeed, Multipsk can be a TCP/IP client and exchange data or commands with a SDR TCP/IP server local or distant ("Remote" button). The standard is a local server (SDR_TCP_IP_xyz.EXE) in "local loop" using the standard IP address 127.0.0.1 and located in the Multipsk directory of your PC. However, it is possible to use a remote server via Internet (with any IP address or DNS).

Moreover, the "+Speaker" may be pushed, to listen to the demodulated sound.

The "Transceiver" window on the "RX/TX" screen permits to control the frequency of the SDR.

……………………………………………………………………………….

Click on the button to reach help.

For the SdR manufacturer

Now what is proposed is only a simulation… For the ones having a SdR receiver (except RTL SDR dongles, directly managed by Muktipsk), if you want to have your SdR directly interfaced to Multipsk (and, perhaps, to other programs in the future), you have to forward this message to your SdR manufacturer. Maybe, he will find interest to develop the necessary server interface, for the satisfaction of his/her clients.

For the SDR manufacturer, here are presented the different files necessary to implement the protocol SDR TCP/IP INTERFACE Version 0. These files are included in the SDR_TCP_IP_INTERFACE_Version_0.ZIP package, available at this WEB address: http://f6cte.free.fr/SDR_TCP_IP_INTERFACE_Version_0.ZIP

· The « SDR_TCP_IP_INTERFACE_V_0.docx » file gives the description of the protocol.

· The « Client_in_C++ » and « Server_in_C++ » files are very simple programs only able to establish a TCP/IP communication. These programs are generated in C++ (C++Builder 6 Borland). They are supposed built in the
C:\SDR_TCP_IP_INTERFACE directory.

· The « Client_in_Delphi » and « Server_in_Delphi » files are very simple programs only able to establish a TCP/IP communication. These programs are generated in Delphi 6 (Borland).

· The « Complete simulation of a SDR TCP-IP client in Delphi » file can be used as a model for a true SDR TCP/IP client program (called « CP » in the protocol), as for example a decoding program. It is issued from Multipsk.

· The « Complete simulation of a SDR TCP-IP server in Delphi » file can be used as a model for a true SDR TCP/IP server program (called « MP » in the protocol). It is interfaced with the SDR hardware and the client program.It has the general equivalent role of the EXTIO file. These two last programs are generated in Delphi 6 (Borland).

Questions of the SDR manufacturer can be asked either to the author (about the protocol) or, in English, to the Multipsk Yahoo group (about needs of SDR users or feedback).

Note about TLE files: if you use the "Satellites" option, don't forget to download

(with the "Downloading" button) the 5 recent TLE files (amateur.txt, argos.txt, orbcomm.txt, stations.txt, weather.txt).

 

 

Multipsk 4.31.3

The Multipsk 4.31.3 fixes several bugs and permits, for licensees, to hide name and address, this for presentations ("Configuration" menu).

The main improvements of CLOCK 1.11 are the following:

· Modern sound cards at 48 KHz are now considered by default ("Sound card 48 KHz" button). However you can keep on with your old 44,1 KHz sound card ("Sound card 44.1 KHz" button).

· New command "Default Parameters": to return to default parameters (included alarm configuration).

Note about limitations of Clock:

The CLOCK limited version allows the extraction of time/date information from the transmitters of FRANCE-INTER (now obsolete), DCF 77, HBG, RUGBY, WWVB, WWV/WWVH, CHU, JJY and GPS, but without synchronization of the computer and digital alarm, functions which are only available with the registered version.

However, the PC synchronisation by an Internet server("Internet time" button) , does not need to have the Multipk/Clock licence.

Note about TLE files: if you use the "Satellites" option, don't forget to download

(with the "Downloading" button) the 5 recent TLE files (amateur.txt, argos.txt, orbcomm.txt, stations.txt, weather.txt).

 

 

MultiPSK (4.31.2)

The main improvements of MULTIPSK 4.31.2 are the following:

 

For about this frequency displayed in the RX/TX screen ("QSO" part): the user can select either the "Receiver frequency" (normal) or the "Carrier frequency" (for a specific need).

· Port choice (14580 or 10152) for APRS-IS servers (in Packet-APRS).

· Pocsag: possibility to display numeric messages as alphanumeric messages (as some of them are, in fact, alphanumeric).

· Possibility to introduce an offset in case of SdR receiver used.
In the "Offset" box of the Multipsk SdR interface, if a SdR receiver is interfaced with Multipsk (through Commander, for example), the user can introduce the offset set in his/her SdR (-24 KHz to 24 KHz), so to have a correct displayed HF frequency.

· Swisslog is now interfaced with Multipsk. For details, see:
http://www.informatix.li/english/Help/Features/HamScope%20Support.htm#MultiPSK

 

New release (4.31) of MULTIPSK

The main improvements of MULTIPSK 4.31 are the following:

1) New mode ORBCOMM (RX)

This system has been developed by the ORBCOMM society which disposes of a constellation of about 37 active LEO ("Low Earth Orbit") satellites, transmitting between 137.2 and 137.8 MHz (+/- 2.5 KHz maximum of Doppler shift).

This system permits:

· to handle messages (encrypted) from ground users (ships, trucks, oil wells...) until other ground users, through the ORBCOMM satellites, the cover being worldwide. These frames are decoded by Multipsk but not deciphered,

· to broadcast identification, frequencies, position and orbital elements pieces of information, not encrypted. These frames are decoded and interpreted by Multipsk.

This mode is available for licencied copies, only (otherwise, the decoding is stopped after 5 minutes).

See general specifications further on.

2) Automatic satellites tracking ("Satellites" button)

The operator has the possibility to automatically track a satellite in position and in frequency (in frequency, if the receiver is under control by Multipsk, possibly via Commander, or directly if the RX is a Funcube or a RTL/SDR key).).

From the "TLE" satellites data files, it will be determinated the satellite position and its frequency during its pass, taking into account the Doppler shift. With this frequency, the receiver will be automatically controlled (in "Transceiver").

The global control may be summarized according to the following diagram:

Satellites data (TLE files)-->Multipsk-->Receiver frequency control

2) Others

· Addition of the Contestia 64-1K sub-mode.

· General use of "Arial" font, instead of "Ms sans Serif", to better manage graphic formats other than 96 pixels per inch.

Note about translation of Multipsk.exe and Clock .exe: the 4.30 version of Multipsk has been completly translated to Spanish by Joachin (EA4ZB), from French. The translation file is on my Web site (http://f6cte.free.fr/Translation_files.htm).

Description of the Orbcomm mode

For Hams and SWL, a signal (transmitted in your area) can be received:

· either from the discriminator output of a classical VHF FM receiver via a direct connection to the PC sound card,

· or, possibly, from the VHF FM receiver speaker through a simple direct connection to the PC sound card,

· or with a SdR receiver (FunCube Dongle, RTL SDR,...) and directly demodulated (in FM) by Multipsk.

Baud rate: 4800 symbols/second.

Modulation : SDPSK (Symmetrical Differential Phase Shift Keying), i.e. a "0" is transmitted with a -90° shift of the carrier phase whereas the "1" is transmitted with a 90° shift. The transmission could be demodulated in PSK, but it is more simple (the minimum Signal to Noise ratio not being so good) to demodulate in FM. This because in PSK, the carrier phase must be followed and locked whereas in FM it is not necessary (the baseband signal is directly supplied).

Reception mode: FM

Shape of pulse : Root Raised Cosine (Alpha=0.4) to limit spectral occupancy.

Bandwidth : 2.5 KHz

Demodulation : non coherent (in FM)

Bit synchronization : automatic using the signal

Data synchronization : a suite of 12 specific bytes.

Correction code: no, but a Fletcher checksum permits to validate each packet of 12 or 24 bytes

Convolution code: no

Interleaving : no

Scrambling: no

Lowest S/N: about +11 dB,

The ORBCOMM satellites transmit identification, frequencies, position and orbital elements pieces of information, not encrypted. These frames are decoded and interpreted by Multipsk. Messages frames are decoded by Multipsk but not deciphered.

ORBCOMM satellites decoding is based on the following document: http://mdkenny.customer.netspace.net.au/Orbcomm.pdf (thanks to Mike Kenny).

 

The main improvements of MULTIPSK 4.30 are the following:

1) New mode ATIS (RX)

ATIS (Automatic Transmitter Identification System) is used by ships for identifying themselves by their call sign (or by their MMSI for visiting ships), on inland waterways (as the Rhine) of the "RAINWAT" area (a part of continental Europe). It is transmitted a short frame (285 ms) sent just after the operator has finished talking and releases his "PTT" ("Push To Talk") button of his FM VHF radio-telephone. It is similar to the VHF GMDSS mode, but only the ATIS code is transmitted (no position and no message). For more information about ATIS, look at http://www.agentschaptelecom.nl/sites/default/files/boekarestovereenkomst.pdf

The radio-telephone frequencies on inland waterways are located on channels spaced by 25 KHz between 156.025 and 161.950 MHz (for example: 160.800 MHz for the Amsterdam port station (channel 04)).

2) Others

· An "AFC" (Automatic Frequency Control) function is available in VDL2 mode, if Multipsk is directly interfaced with the SdR.

· Improvement of the GMDSS VHF decoding.

· Addition of the Olivia 32-2K sub-mode.

 

 

New release (4.29.2) of MULTIPSK

The new release of MultiPSK (4.29.2) and Clock (1.10.2) are on my Web site (http://f6cte.free.fr).

Multipsk associated to Clock are freeware programs but with functions submitted to a licence (by user key).

The main improvements of MULTIPSK 4.29.2 are the following:

· In AUTEX mode, all received and transmitted messages are displayed in a "SMS" form in a specific window. Positions (by Locator or latitude/longitude) can be transmitted and displayed. It is also possible to exchange small files (<=10Kb).

· In 4285 mode, the "Inversion" button permits to invert the bits polarity. For example, an Italian station (from Naples) transmits, sometimes, in 600 Long / 5N1 / Inverted on 8123.2 KHz. The "Auto" button permits to automatically detect the bits polarity.

· For RTL/SDR keys, it is proposed, thanks to the "RTL and mode selection" button, to select the direct sampling of the I branch: this experimental mode permits, after key modification (see http://www.rtl-sdr.com/rtl-sdr-direct-sampling-mode/), to receive between 0 and 14.4 MHz (HF frequencies). However, the modification is difficult because components are tiny. Moreover, the key sensitivity is very bad.

 

 

The main improvements of MULTIPSK 4.29.1 are the following:

· New message mode in all ARQ modes

The "Message mode" button, in pushed position, allows the user, for all "ARQ" modes (Packet FSK110-300-1200 bauds/Packet PSK31-63-250-1200 bauds, PAX, PAX2, 141A(ALE), ALE400, AUTEX 2, 4, 7,13) to prepare the message and then to send it when it is ready. The transmission is done with the "Send" button or with the key.

If not in "message mode", the message is sent as and when it is written (previous way to do). In "message mode", the "Transmission on " option is ignored.

Display of the GMDSS coast stations positions on maps.

Update of the Shipdata.txt file and display of the ship type, if known, in GMDSS and AIS.

The "CPU" button (at the top of the RX/TX screen) gives the number of cores of the CPU, followed by the CPU theoretical speed and the volume of data (RX/TX). It allows the activation of the CPU and memory measurements of the PC.

New macro (for "Alignment on an AF frequency") allows an action equivalent to push on the "Align" button of the "Transceiver" form.

Volume of data received or transmitted limited to 60 Mb with automatic back-up beyong 60 Mb.

Note about translation of Multipsk.exe and Clock .exe: the 4.29 version of Multipsk has been completly translated to Spanish by Joachin (EA4ZB), from French. The translation file is on my Web site (http://f6cte.free.fr/Translation_files.htm).

INSTALLATION AND START-UP OF MULTIPSK AND CLOCK WITH THE NEW SETUP PROGRAM

To install the programs on your hard disk:

1) Download "MULTIPSK_setup.exe" from the F6CTE WEB site

(http://f6cte.free.fr/index_anglais.htm). The links are:

* "To download the last version of Multipsk and Clock, click here" or

* "Download Here".

Afterwards click on "Run" (or "Execute") (rather that to store it).

ATTENTION: the Windows firewall perhaps will block this file. You will have to unblock it.

NOTE: as there is no change in the Windows registers base (and so no problem of uninstallation), the application files could be installed manually (with Windows Explorer) in any directory.

2) During the execution:

* the setup program (based on a "Inno Setup" script) will ask to confirm the

detected language ("English"). The other proposed language is French,

* by default, the user will confirm the proposed options,

Note: your configuration files will not be modified, because they will be

automatically created, only in case of absence.

* if the installation directory yet exists, the setup program could ask confirmation

of this directory. You will answer "Yes", except a particular user need.

Note: if you are installing the program for the first time, confirm "C:\MULTIPSK".

If you are updating any previous version, give the yet used directory name.

Two links on MULTIPSK and CLOCK will be automatically created on the desktop as well as a "Multipsk" group in the menu.

Start the MULTIPSK program either with the "MULTIPSK" link or from the menu. The configuration screen opens first. You must click the RX/TX button to access the main screen.

IMPORTANT: Clock must be started as administrator to be able to update the PC time. For this, just right-click on the Clock.exe file, select "Properties" and choose the "Compatibility properties" or "Advanced properties". Check on "Run as administrator" (Level privilege).

The help file can be started from MULTIPSK, or by double-clicking on "HELP_PSK.CHM". For help on CLOCK, click "HELP_CLO.CHM".

In case of error message such as "Action cancelled" or "DNS error", to unblock the blocked CHM file:

* In Windows Explorer, right-click the blocked file, and then click Properties.

* In the General tab, click Unblock.

Hints and contextual help:

* many buttons have a hint which is obtained by remaining a fraction of second

with the mouse pointed on the button,

* a contextual help (i.e. depending on the selected mode) is obtained by clicking

with the right button of the mouse, the cursor of this one being located over

a mode button ("BPSK31", for example).

Multipsk is conceived for a Windows system.

Note for the LINUX users (under WINE):

The DLLs are not recognized under Linux. Multipsk uses few DLLs, and only for auxiliary functions which are:

* the RTL/SDR interface for SdR receivers,

* PC identification,

* the parallel port handling,

* PSK-reporter,

* option "DirectSound" for the pseudo-modes "Filters" and "Binaural".

To avoid an error message, select the last option of the menu.

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