Classifier Option (subject to change without notice)

Highlights

  • Automatic classification of radio data signals.
  • Automatic classification and code check (CCC) of radio data signals.
  • Extension to the W61PC, W61LAN, and W-CODE WAVECOM decoders.
  • Fully integrated into the WAVECOM user and remote interface.

Classifier

The ability to rapidly identify un­known signals has become an essential requirement in signal analysis.


The automation of the signal classification process relieves the operator from manual evaluation, which otherwise requires considerable skill and experience. The combination of a classifier and a decoder thus satisfies the re­quirement for an automatic sys­tem that is able to rapidly and reliably determine the charac­teristics of radio data transmis­sions within the signal spectrum being monitored accurately.


The classification algorithm determines the center frequency, speed (symbol rate), shift, bandwidth and modulation.


The detection and classification results are displayed in a list together with all parameters and are fully integrated into the WAVECOM® user interface.

Spectrum/Sonagram display

In this pane the monitored frequency spectrum is displayed. After classification has completed the classified signals are indicated in the spectrum display.

Classification

The results of the classification are shown as a list in a second pane. The following parameters are provided for each classified signal:

  • Modulation type
  • Center frequency of the signal
  • Number of car­riers in the case of multi-carrier FSK
  • Baud rate in the case of FSK or PSK signal
  • Frequency shift in the case of FSK signal
  • Bandwidth

Additional information

Additional FSK, MFSK and PSK information on symbol timing and constellation, baud rate and frequency vs. time is graphically displayed in a separate window when a classified signal is selected from the list.

ParameterW-CLASSIFIER-NB
W61CL
W-CLASSIFER-WB
Bandwidth 4 kHz or 8 kHz

0.5 kHz, 1 kHz, 2 kHz, 4 kHz,8 kHz,
12 kHz,  24kHz,  48 kHz or  96 kHz

Sampling interval (Ts)

1.6 or 3.2 sec

1.6 or 3.2 sec

CWTs=1.6: 6 to 60 Bd
Ts=3.2: 3 to 60 Bd
Ts=1.6: 6 to 60 Bd
Ts=3.2: 3 to 60 Bd
FSK30 to 3000 Bd, Shift ≤ 3500 Hz

30…60 kBd, Shift ≤ 30 kHz

FSK-4/F7B

30 to 300 Bd, Shift ≤ 3500 Hz

30…300 Bd, Shift ≤ 3500 Hz

MFSK4-36 Tones4-36 Tones
PSK 2/4 Variant A/B

30 to 3000 Bd30 Bd to 60 kBd

PSK 8/16 Variant A/B

30 to 3000 Bd30 Bd to 60 kBd

CIS-12

120 Bd120 Bd
OFDM25-512 Carriers

25-512 Carriers

OQPSK

25 Bd to 2400 Bd25 to 30 kBd

Voice (AM/FM/USB)

NoYes
Sub-carrier modulation (AM, FM, SSB)

NoCorresponds to the values
 for the primary modulation type

Classsifier-Code-Check

The Classifier-Code-Check is a versatile analysis tool for the classification of unknown signals and the determination of the protocol (mode) in use. The CCC will attempt to process all signals within the bandwidth of the classifier (NBCL or WBCL). The CCC processes input signals in up to four successive steps as shown in the block diagram below. The user can select how many steps should be involved in the analysis of the signal(s) under investigation.



The possible signal paths of the CCC are shown below:

  • The classifier attempts to classify the input signals according to their modulation formats.

  • The table check will check the signal against the entries of an XML-formatted list.

  • The code check will check by attempting synchronization.

  • Finally the signal may be forwarded to a decoder for output.



W-SAT or W61SAT, INMARSAT Option


WAVECOM recommends to use the W61PC/LAN together with the W61SAT-Option.
The advantage of this combination is the SDR (Software Defined Radio) of the W61PC. This feature makes it possible to build a reliable, optimized, straightforward and cost effective monitoring system in combination with a L-Band to 70 MHz down converter.

For W-CODE an external receiver with IF output and hardware to convert the IF signal to IQ-data is required.

 
The W61PC is the first choice to build a cost efficient satellite monitoring system for INMARSAT due its onboard, tunable 70 MHz input (no external receivers are required).
Regarding the system requirements for a L-band  monitoring system, consult our application note
For decoding a SNR of >15 dB (recommended 20 dB) is required.
 
The SAT Option consists of:


EasySATSystem
A smart software, controlling multiple W61PC cards for the INMARSAT B, C, M or mM modes. The control software is included in our W61SAT-Option. Up to 10 cards may be simultaneously controlled from our control software. Setup is done with a text configuration file.

INMARSAT B
The W61PC monitors the control channel, and upon initiation of a new session with a mobile terminal, it automatically switches to the assigned traffic channel for monitoring. To limit the volume of monitored traffic, a watch list may be created containing target MES IDs. Monitored fax, voice, telex and data sessions are stored in files. A fax viewer is included with the application. Voice is recorded in .wav files and streamed to the standard sound output of the system for live monitoring.

INMARSAT C (TDM, TDMA, EGC)
With the SAT-C-TDM and SAT-C-TDMA mode, duplex data (forward and return) traffic can be monitored.
The INMARSAT C satellite system has an inherent capability, known as Enhanced Group Call (EGC), which allows broadcast messages to be made to selected groups of ship stations. Two types of EGC services are available, SafetyNET and FleetNET. Both systems are part of our SAT-C-TDM mode. An Auto-NCSC mode allows to record the traffic for an particular MES. After a channel assignment has been received, the decoder switches to the traffic channel and decodes the traffic for the MES of interest.

INMARSAT M
The W61PC monitors the control channel, and upon initiation of a new session with a mobile terminal, it automatically switches to the assigned traffic channel for monitoring. To limit the volume of monitored traffic, a watch list may be created containing target MES IDs. Monitored fax, voice, telex and data sessions are stored in files. A fax viewer is included with the application. Voice is recorded in .wav files and streamed to the standard sound output of the system for live monitoring.
 
INMARSAT mM
The W61PC monitors the control channel, and upon initiation of a new session with a mobile terminal, it automatically switches to the assigned traffic channel for monitoring. To limit the volume of monitored traffic, a watch list may be created containing target MES IDs. Monitored fax, voice, telex and data sessions are stored in files. A fax viewer is included with the application. Unprocessed voice-packets are stored in binary .txt files. For miniM voice playback, please enquire.

INMARSAT AERO-P
The W61PC monitors the Aero forward P-channel (control and forward messages)common to all Aero modes (L, H, H+ and I).

 The decoder is currently a beta version awaiting final

completion and presents control and Data-3 messages in hexadecimal format whereas as Data-2 (ACARS) is represented in clear

text.