WSF_COMM_MEDIUM_UNGUIDED

medium WSF_COMM_MEDIUM_UNGUIDED

Script Class WsfCommMedium

Script Class WsfCommMediumModeUnguided

medium <name> WSF_COMM_MEDIUM_UNGUIDED
   ... medium Commands ...
   ... WSF_COMM_MEDIUM_GUIDED Commands

   snr_transfer_rate_table ...
   bit_error_probability ...
   error_correction ...
   bit_error_rate_ebno_table ...

   mode <mode-name>
      ... WSF_COMM_MEDIUM_GUIDED Commands
      snr_transfer_rate_table ...
      bit_error_probability ...
      error_correction ...
      bit_error_rate_ebno_table ...
   end_mode

end_medium

Overview

WSF_COMM_MEDIUM_UNGUIDED is a generic unguided medium type.

An unguided medium is a type of medium not restricted by a physical medium, typically associated with the usage of electromagnetic radiation to convey a signal. This medium type provides a generic specification of an unguided medium that has typically been found in previous versions of AFSIM with certain model definitions.

This medium type is valid for the following communication object models in the AFSIM core.

Note

Currently, routers do not allow for hardware based definitions for the transmitter or receiver. Usage of the unguided medium for a router will currently use the transmitter/receiver capabilities of the comm device originating the message.

Commands

snr_transfer_rate_table <absolute-units><data-rate-units><SNR-value 1> <transfer-rate-value 1> … end_snr_transfer_rate_table

Specifies a table that maps signal-to-noise-ratio values to message transfer rates. The SNR-Transfer-Rate table will be interpolated. If a table is specified, the table transfer rate values will override the value specified with the transfer_rate command.

Note

SNR Transfer rate table is mutually exclusive with the Eb/No vs BER table. The last one specified will be used.

Default: none

SNR-Transfer-Rate-Table Example

snr_transfer_rate_table
   dB bit/s
   0  100
   1  100
   2  90
   3  80
   4  40
   5  20
   55 10
   70 1
end_snr_transfer_rate_table
bit_error_probability <real-value>

Optional parameter that defines the system designed bit error rate probability. It is used to pick the Eb/No values from the Eb/No vs. BER table. Must be greater than or equal to zero.

Default: 0.0

error_correction <real-value>

Optional parameter that determines how much error correction will be applied when using Eb/No to calculate data rate. Must be between 0.0 and 1.0. Units are assumed dB.

Default: 0 dB

bit_error_rate_ebno_table <absolute-units><ratio-units><BER-value 1> <Eb/No-value 1> … end_bit_error_rate_ebno_table

Optional table that defines the Energy per Bit to the Spectral Noise Density (Eb/No) vs. Bit Error Rate (BER). Used in conjunction with the bit_error_probability and error_correction to calculate the data transfer rate over the medium. When using this table Data Rate = SNR* Error Correction * ( Bandwidth / Eb/No ). The Bit-Error-Rate-EbNo-Table will be interpolated. If a table is specified, the table transfer rate values will override the value specified with the transfer_rate command.

Note

Units for the values in the table are optional and if not entered are assumed to be dimensionless for BER and dB for Eb/No.

Note

Eb/No vs BER table is mutually exclusive with the SNR Transfer rate table. The last one specified will be used.

Default: none

Bit-Error-Rate-EbNo-Table Example

bit_error_rate_ebno_table
  0.00000001 12
  0.0000001  11.3
  0.000001   10.3
  0.00001    9.5
  0.0001     8.3
  0.001      6.5
  0.01       4.3
  0.1        0
end_bit_error_rate_ebno_table

Military Specific

This medium type is valid for the following communication models in wsf_mil.