RF-Link Technology NL6000 manual Crc, Fec

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∙Mobile Data mode

Table 2 summarizes the characteristics of each transmission mode

	Basic Telemetry	Enhanced Telemetry	Mobile Data
	Mode	Mode	Mode
Spectral Pre-coding	Yes	Yes	Yes
Randomization	Yes	Yes	Yes
CRC	Yes	Yes	Yes
FEC	No	Yes	Yes
Interleaving	No	No	Yes

Table 2: Transmission Mode Characteristics

To select the best transmission mode for a unit, consider the following factors:

∙Signal strength between the unit and its destination unit(s)

∙Reliability of the path between the unit and its destination unit(s)

∙Noise, RF interference, and fading expected on the radio channel

∙Movement of the unit or movement of its surroundings

Each transmission mode is designed to provide a different level of error control. The level of error control influences the optimum packet size that will produce the desired throughput. Use the scenarios on the next page to help determine which Transmission Mode and Maximum Packet Size is best for a unit.

Note: If you are not sure which mode to use, use Enhanced Telemetry mode.

You can configure the transmission mode and packet size parameters differently for each unit in the network. All transmission modes share a common mode field as part of the packet. This field allows the receiving modem to determine the mode prior to decoding a received message.

Scenario #1

Description: You have above average signal strength and a reliable path between the radio modem units. You do not expect noise bursts, RF interference, or signal fading to corrupt the radio data link.

Best Choice: Basic Telemetry Mode

Because you have a clean channel, use the mode that uses the least overhead for each packet. Basic Telemetry mode uses error detection only, so

RF Neulink

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NL6000 User Guide

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Contents NL6000 Wireless Modem Copyright Table of Contents RF Neulink NL6000 User Guide RF Neulink NL6000 User Guide Use the NL6000 in a Simple Configuration Product OverviewFeatures Acknowledgement Configuration TemplatesSingle and Multi- Point Addressing Auto-TransmitFCC Part Safety WarningRegulatory Information 406.0 to 406.1 MHz OperationSpecifications General SpecificationsTransmitter UHF Radio SpecificationsCurrent Drain at 12 ReceiverVHF Radio Specifications Parts Description Hardware Installation and OperationPower Connections Serial PortDTE DCEOperation Antenna ConnectionLEDs LEDPrerequisites Software ConfigurationTechnical Support PreparationUnique Data Requirements for a Base Station Source and Destination AddressingBehavior of Repeater Units Addressing with WildcardsRepeat from a Base to a Remote Repeat to Multiple Remotes using Wildcard Transmission Mode Packet Data OptionsCRC FECRF Neulink NL6000 User Guide Over-the-Air Data Rates AcknowledgementsSerial Connection to an I/O Device Carrier Sense Multiple AccessDCD Mode Basic Serial ParametersPlanning the RF Channel Factory Default ParametersPre- and Post-Data DCD Time Procedures Select Network ä Unit TypeGeneral Procedures Displaying the Configuration Summary Window Returning to the Previous MenuSetting the Unit ID Myid Select Network ä Myid Radio Network SetupSetting the Unit Type Select Network ä Unit Type Setting the Target Unit ID ToidSerial Connection Setup Data Setup Setting the Packet Mode Select Network ä Packet ModeSetting the Contention Option Select Network ä Contention Setting the Data Rate Select Network ä Data RateSetting the Request ACKs Option Setting the Max Retries OptionRepeater Setup Trigger ID Value UseDownloading a Software Upgrade File ManagementSaving Parameters to Disk Select Save/Restore Parameters ä Save Parameters to DiskRestoring Parameters from Disk Restoring Default Parameters Menu Quick Reference Main Menu Summary WindowSerial Menu DCD RS-232 SubMenu Network Menu Repeater SubMenu Radio Menu Diagnostics Menu Save/Restore Parameters Menu Other Considerations TroubleshootingDuty Cycle Use a Slower Baud Rate Use a Fully-Wired RS-232 CableUnit Does Not Enter Programming Mode Use a Faster Baud RateSetting the Power Value Appendix a Diagnosing and Correcting Performance ProblemsSetting the Frequency Trim includes setting Power Select Diagnostics ä Transmit Continuous Random DataSelect Diagnostics ä Transmit 100 Hz Square Wave Setting the Deviation and Balance∙ Select Frequency Trim from the Diagnostics menu ∙ Select Radio Ä Transmit Frequency for Active Channel∙ Select Diagnostics ä Receive Diagnostic Mode Setting the Receive Gain∙ Select Deviation from the Diagnostics menu ∙ Select Diagnostics ä Receive GainCategory Parameter Default Value Custom Value Appendix B Factory Default ParametersFactory Default Values Index RF Neulink NL6000 User Guide