OCR220 Radio Module
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Product Information: OCR220 Radio Module
Specifications:
- Description: 220MHz Railroad Communications
Module - Manufacturer: GE MDS, LLC 175 Science Parkway
Rochester, NY 14620 USA - Operating Frequency Range: 217-222MHz
(Transmit) / 217-222MHz (Receive) - Output Power: +33dBm
- Modulation: GMSK, Bandwidth Time = 0.3,
9615bps - Bandwidth: 12.5kHz
- Channel Spacing: 12.5kHz
- Transmitter Architecture: Synthesized Direct
Conversion - Receiver Architecture: Synthesized Direct
Conversion - Reference Clock: 39MHz, 0.5ppm
- RF Interface: SMB (Female) for 220MHz Tx/Rx
functions, Cell Main, and Cell Aux - Data Interface: Samtec LSS Series 20-pin board
to board connector providing Serial (Diagnostics/Configuration) and
Serial (Payload data) - Operating Temperature Range: -40 to +70°C
- Module Operating Voltage: 11-15VDC (Supplied
through edge connector) - Module Operating Current: 1.0A (At maximum TX
RF power operation) - Module Dimensions: 3.5×2.0x1.0
Product Usage Instructions:
Module Integration Guide:
The OCR220 radio module consists of a radio PCB and a processor
PCB. The radio PCB includes a Telit LE910C4 Cellular Module for LTE
communications and operates independently from the 220MHz
transceiver. The processor PCB carries an IMX6 device for managing
data packets between the transceiver and cellular modules.
Interface Specification:
The module features a Samtec LSS Series 20-pin board to board
connector for data/power interfaces to the processor board. The
host interface pinout is provided in Table 2 for configuration.
Application Information – Radio Network Operation:
The OCR220 module operates within the frequency range of
217-222MHz for both transmit and receive functions. It complies
with FCC CFR47 Part 90 and ISED RSS-119 regulations.
Frequently Asked Questions (FAQ):
Q: What is the operating temperature range of the OCR220
module?
A: The OCR220 module has an operating temperature range of -40
to +70°C.
Q: What is the output power of the OCR220 module?
A: The OCR220 module has an output power of +33dBm.
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OCR220 Radio Module
Module Integration Guide Revision 1.0
Prepared by: GE MDS Engineering Team
17-JULY-2023
OCR220: Module Integration Guide
Table of Contents
General Description …………………………………………………………………………………………………………………….. 2 Specifications ……………………………………………………………………………………………………………………………… 3
Table 1: OCR220 Module Specifications ……………………………………………………………………………………… 3 Interface Specification …………………………………………………………………………………………………………………. 4 Application Information: Radio Network operation …………………………………………………………………………. 5
Note about terminology used ………………………………………………………………………………………………… 5 LCU-OCU Direct Mode (No Repeaters) ……………………………………………………………………………………….. 5 LCU-OCU Mode with Coordinating Repeater ………………………………………………………………………………. 6 Multiple LCU-OCU with Multiple Repeaters ………………………………………………………………………………… 7 User Interface …………………………………………………………………………………………………………………………….. 8 Regulatory Information for Limited Modular Use ………………………………………………………………………….. 11 Applicable FCC Rules ………………………………………………………………………………………………………………. 11 Operational use conditions……………………………………………………………………………………………………… 11 Limited Module Host restrictions …………………………………………………………………………………………….. 11 Trace antenna designs ……………………………………………………………………………………………………………. 11 RF exposure considerations …………………………………………………………………………………………………….. 11 Antennas ………………………………………………………………………………………………………………………………. 11 Labeling and Compliance ………………………………………………………………………………………………………… 12 Test Modes……………………………………………………………………………………………………………………………. 13 Additional testing for Part 15 Subpart B ……………………………………………………………………………………. 13 EMI Considerations ………………………………………………………………………………………………………………… 13 Changes………………………………………………………………………………………………………………………………… 13 Process for FCC Compliance of OCR220 Installed in Host ……………………………………………………………….. 14 Receiver sDoC Procedure………………………………………………………………………………………………………… 14 Transmitter Conducted Emissions Assessment ………………………………………………………………………….. 14 Transmitter Radiated Emissions Assessment …………………………………………………………………………….. 15
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OCR220: Module Integration Guide
General Description
The Association of American Railroads has established a specification for the remote control of locomotives. The Remote-Control Locomotive (RCL) protocol is transmitted wirelessly from external control points to the locomotive. GE MDS is providing the equipment that provides the wireless physical layers over which the RCL communication protocol is shared in the 220MHz band. The OCR220 Radio Module (Figure 1) consists of a set of (2) PCB assemblies: a processor board and radio board. The radio board (Figure 2) and processor board (Figure 3) are fastened to each other and used as a board set inside of the host device. This module has been designed exclusively for installation into a client host device called the Wabtec Operator Control Unit (OCU). This module has a form factor of approximately 3.5″x1.5″x1.”
Figure 1: OCU220 Module. Bottom PCB is radio (Figure 2) and Top PCB is processor (Figure 3)
An image of the OCR220 radio PCB is shown in Figure 2, Below. This PCB is in a form factor approximately 3.5″x1.5″x0.5″, has a 60 pin board to board connector for data/power interfaces to the processor board, and SMB connectors for antennas. The OCR220 includes a Telit LE910C4 Cellular Module for LTE communications. This cell module does not operate at the same time as the 220MHz transceiver; the host device chooses the single radio interface type for communications.
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Figure 2: OCR220 Radio PCBA
OCR220: Module Integration Guide
The processor board is shown in Figure 3, below. The processor carries an IMX6 device to manage data packets to/from the 220MHz transceiver and Cellular modules and includes the interface connector to the host with Ethernet, Serial, and Power.
Figure 3: OCR220 Processor PCBA
Specifications
Table 1: OCR220 Module Specifications
Description:
220MHz Railroad Communications Module
Manufacturer:
GE MDS, LLC 175 Science Parkway Rochester, NY 14620 USA
Operating Frequency Range: 217-222MHz (Transmit) 217-222MHz (Receive)
Applicable Regulations:
FCC CFR47 Part 90 (217-222MHz) ISED RSS-119 (217-220MHz)
Output Power:
+33dBm
Modulation:
GMSK, Bandwidth Time = 0.3, 9615bps
Bandwidth:
12.5kHz
Channel Spacing:
12.5kHz
Transmitter Architecture:
Synthesized Direct Conversion
Receiver Architecture:
Synthesized Direct Conversion
Reference Clock:
39MHz, 0.5ppm
RF Interface:
SMB (Female) for 220MHz Tx/Rx functions
SMB (Female) for Cell Main
SMB (Female) for Cell Aux
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OCR220: Module Integration Guide
Data Interface:
Samtec LSS Series 20-pin board to board connector provides:
Ethernet 100MB (Maintenance/Firmware updates)
Serial (Diagnostics/Configuration)
Serial (Payload data)
Operating Temperature Range: -40 to +70C
Module Operating Voltage: 11-15VDC (Supplied through edge connector)
Module Operating Current: 1.0A (At maximum TX RF power operation)
Module Dimensions:
3.5″x2.0″x1.0″
Interface Specification
The 20pin Host interface pinout is as shown in Table 2, Below.
Table 2: Host Interface Pinout The ethernet connections, pins 9,11, 15, and 17 for RX and TX differential pairs, respectively, are transformerless without auto MDIX or autonegotiation. The Host device should be set to operate at a fixed 100Mbps.
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OCR220: Module Integration Guide
Application Information: Radio Network operation
The OCR220 is a half-duplex radio module designed for use in TDMA RCL networks. The unit is designed for installation in the Operator Control Unit (OCU) to communicate with other radio products in a railyard, including locomotive (Locomotive Control Unit, or LCU) or Repeaters.
This product is configured with a list of TX and RX frequency pairs that are entered by an authorized representative of the railroad communications team. The frequencies are scanned in receive mode until a reliable RF link is found.
Note about terminology used The frequency hopping referred to within this document is not a form of spread spectrum, but rather a method the railroad spectrum licensee uses to automatically chose other frequency pairs they have been assigned when a channel is congested and/or has poor signal conditions to sustain reliable communications. The system will step through two frequency pairs in four seconds.
Repeaters in the railyard are devices that can receive transmissions from LCU or OCU radios, demodulate the data, interpret the payload, and transmit new data to the LCU or OCU radios if needed. The term repeater in this sense is different than the repeaters classified by the FCC or ISED.
LCU-OCU Direct Mode (No Repeaters)
In its simplest form the RCL system can operate in a standalone fashion with no repeaters present. Prior to on-air deployment, an off-line configuration is required at which time the two OCUs are “paired” to their LCU. This initialization ensures that only the two pre-defined OCUs can communicate with and control the LCU. After initialization, when the units go live in the yard they will operate in Distributed Coordination Mode, also known as Direct Mode, and the wireless communication between the devices is done with a TDMA time slot channel changing scheme.
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Figure 4: LCU-OCU Direct Mode
OCR220: Module Integration Guide
LCU-OCU Mode with Coordinating Repeater
The system contains one Repeater which is configured in Coordinator mode. The LCU / OCUs are paired ahead just like in the Single-RCL use case, they boot into the slot-hopped DCM and establish communication with each other. Simultaneously, LCU discovers and establish communication with the coordinator and when the Distributed Coordination Mode (DCM) exit criteria are met, the LCU drives the system to switch to the Centralized Coordination Mode (CCM) which is controlled by the Coordinator. In CCM the timeslots allocated to the individual RCL systems in the yard is done intelligently by the Coordinator to prevent over-the-air packet collisions. This use case is also advantageous in that the overall wireless coverage is improved by having the secondary path between the LCU and OCUs that goes through the Coordinator.
Figure 5: LCU-OCU Mode with Repeater
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OCR220: Module Integration Guide
Multiple LCU-OCU with Multiple Repeaters
The system contains one Repeater which runs in Coordinator mode and one or more additional Repeaters acting as Satellites. The Coordinator and Satellites are linked together via a high-speed backbone on Ethernet, fiber, or highspeed wireless. The system behaves the same as the SingleRepeater Use Case with one exception: all the wireless data packets received by the Repeaters are shared on the backbone. With the sharing of the packets across all the Repeaters the control algorithm can determine which Repeater is best to re-transmit to each OCU or LCU in the yard, resulting in the optimal coverage/communication scenario for the overall system.
Figure 6: Multiple LCU-OCU Mode with Multiple Repeaters
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OCR220: Module Integration Guide
User Interface
When evaluating the OCR220 radio module outside of an OCU host, this requires a GE MDS Test fixture that breaks out the connections of the 20-pin module edge connector to external Serial connections that a user can access with a PC. This test fixture (Figure 8, below) is not distributed to external facilities other than regulatory testing agencies or the integrator for their host integration activities.
Figure 8: OCR220 Module Installed on test fixture
The User interface of OCR220 is in command line format. It is accessed with a terminal program such as Teraterm or Putty. The serial port operates at 115.2kbps, 8N1.
SREV [TIME]
Display MCU (TI) software revision. Entering the optional time argument causes a build timestamp to be displayed.
PASS xxxx
By entering a password additional engineering and factory only commands may be used.
RX xxx.xxxxx
This sets the receive frequency used in test mode. Up to 5 digits can be entered after the decimal point, but trailing zeros do not have to be entered. Range checking is not performed.
TX xxx.xxxxx
This sets the transmit frequency used in test mode. Up to 5 digits can be entered after the decimal point, but trailing zeros do not have to be entered. Range checking is not performed.
MFREQ1 xxx.xxxxx BFREQ1 xxx.xxxxx MFREQ2 xxx.xxxxx BFREQ2 xxx.xxxxx MFREQ3 xxx.xxxxx BFREQ3 xxx.xxxxx MFREQ4 xxx.xxxxx BFREQ4 xxx.xxxxx
These commands set the corresponding receive & transmit frequency pair used as specified by the DSP (mac controller). Up to 5 digits can be entered after the decimal point, but trailing zeros do not have to be entered. Range checking is not performed.
PWR x KEY
This sets the transceivers output power. Valid options are H, L, and XL, for “high”, “low”, and “extra low” power settings, respectively. (At calibration time, “H” is normally associated with 2 watts, and “L” is normally associated with 0.5 watts, and “XL” is associated with FPWR 1).
This is a test command that allows the user to unconditionally key the radio for test purposes.
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OCR220: Module Integration Guide
KEYR TONEKEY
Key the radio with random data for test purposes. Key the radio unmodulated for test purposes.
DKEY MODEM
This is a test command that cancels the affect of a previous KEY command.
This displays the current modem configuration. (Normally BAUD 9600, BT=.3, BW=12.5KHz). This can be used to determine if a modem test configuration is in effect (i.e., tones or analog operation).
SER
This displays the serial number of the radio (separate versions of this command exist for MCU &
DSP)
RSSI RSSI ON
This causes the receiver to output the current value of RSSI. The output range is 50 dBm (strongest signal) to 120 dBm (no signal). This causes the receiver to output the current value of RSSI once every 3 seconds.
RSSI OFF
Turns off the continuous RSSI reading
ATTN (ON/OFF) This puts the LNA in low gain mode (ON) or normal gain mode (OFF)
HELP
Displays this list of commands
PROG INIT
This initiates a procedure to reprogram the FLASH memory for the radio.
This resets some common user programmable settings to the factory default. · MODEM BAUD=9600, BT=.3, BW=12.5KHz · RX 220.00000 MHz · TX 220.00000 MHz · BFREQ1 221.10625 MHz · MFREQ1 220.106250 MHz · BFREQ2 221.11875 MHz · MFREQ2 220.11875 MHz · PWR=H · CAL DEV 40 · POLL STARTUP OFF
IEEP MM xxxx ALARM
FPWR xxx
This resets all non-volatile memory. The radio will require factory recalibration.
Used to directly view or modify a memory location.
Returns a 4-digit hexadecimal alarm code. 0x8000 = Out-of-Lock 0x4000 = Not Calibrated
This is used to adjust output power. The valid range is 0 to 4096.
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OCR220: Module Integration Guide
CPWR x
RSSL RSSH
This is used to associate the current output power with a pre-programmed PWR command setting. Valid options are H and L, for “high” and “low” power settings, respectively.
Used to calibrate the RSSI while injecting a Low signal level (-90 dBm).
Used to calibrate the RSSI while injecting a High signal level (-70 dBm).
CAL CF xxxx
This allows calibration of the Center Frequency. The digits xxxx are in the range of 32767 to 32767 and represent a correction to be added to the operating frequency. (Not in Hertz)
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OCR220: Module Integration Guide
Regulatory Information for Limited Modular Use
Applicable FCC Rules
This module is designed as a Part 90 device operating in the 217-222MHz band as detailed in Table 1: OCR220 Module Specifications.
WARNING: Any changes or modifications to the module not expressly approved by party responsible for compliance ( GE MDS, LLC) could void the user’s authority to operate the equipment.
Operational use conditions
This module may only be used with the Wabtec Operator Control Unit (OCU). This module is intended for use in locomotive applications. This product is designed for operation from -40 to +70C and is not intended for outdoor use. This device is for professional installation only. Output power is configurable up to +33dBm and must be adjusted to accommodate for antenna gain to conform to the specific ERP limits of the FCC licensee using this product.
Limited Module Host restrictions
The OCR220 radio module features a unique board to board connector and requires limited supply voltage provided by the Wabtec OCU.
Trace antenna designs
The OCR220 does not include any trace antenna designs, and therefore there are no applicable considerations for this topic.
RF exposure considerations
The radio equipment described in this operation emits radio frequency energy. The concentrated energy from a directional antenna may pose a health hazard. Persons may not come closer than 44 centimeters to the front of the antenna when the transmitter is operating with a 2.0dBi antenna and configured for +33dBm output power.
Antennas
The conducted output power of the module installed in the host chassis is up to +33dBm. This module is intended for professional installation only for integration into the Wabtec OCU host. The antennas that have been tested and approved for use with this module are as listed in Table 3, below.
Manufacturer
Model
PCTEL
BMAXMFTS
PCTEL
PCT-RSA-20
Sinclair
ST221-SfeNF
Sti-Co
HDLP-NB-220
Table 3: Antennas tested with the OCR220 Module
Type Omnidirectional Omnidirectional Omnidirectional Omnidirectional
Gain 0.0dBi 2.0dBi 2.12dBi 2.12dBi
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OCR220: Module Integration Guide
Labeling and Compliance
Figure 8, below, is an example of the label that must be present on the Host: Wabtec OCU as shown in Figure 9. This label is installed at the Wabtec factory during production.
Figure 8, above: OCU Label showing “Contains E5MDS-OCR220, 101D-OCR220” as highlighted
Figure 9: Location of label detailed in Figure 8, placed on the underside of the Wabtec OCU Page 12 of 15
OCR220: Module Integration Guide
Test Modes
The Wabtec OCU does not externalize module operational test modes to the end user. Test and alignment are performed during production calibration. Prior to product shipment, Wabtec must perform applicable tests in the production environment to ensure that the completed assembly is operating satisfactorily.
Additional testing for Part 15 Subpart B
The Wabtec OCU is the only permissible host for the GE MDS OCR220 Module. Wabtec must test and ensure that the OCU host complies with FCC Part 15 Subpart B when operating with the OCR220 radio module in place.
EMI Considerations
The OCR220 Radio Module includes integrated shielding for the RF section This module conforms to all applicable Part 15 and Part 90 requirements without needing to be installed inside of the host enclosure. The Wabtec OCU host does not allow multiple modules (Cellular and 220MHz) to operate simultaneously,
Changes
GE MDS does not offer for sale the OCR220 as a standalone device for integration with other hosts. As the grantee of the host and this module, GE MDS does not have any offer guidance or technical contacts to enable third party entities to create such products.
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OCR220: Module Integration Guide
Process for FCC Compliance of OCR220 Installed in Host
This section describes the procedure for ensuring that full compliance of the OCR220 Module is maintained when installed in the Wabtec OCU host. The module is evaluated inside of the Wabtec OCU using the sDoC procedure established by the FCC for the receiver. The steps below additionally identify a process to assess Transmit and conducted and radiated emissions when the OCR220 Module is operating at its lowest and highest frequencies, and highest transmitter power setpoint when installed in the host. The transmitter assessment steps ensure no degradation of transmitter performance when operating in the host.
1. Install OCR220 Radio Module into OCU Chassis per the “Module Integration Instructions” section of this document.
2. Attach the appropriate power source to the OCU host. 3. Connect a PC for configuration of the OCR220 module for testing purposes. 4. Log in to the EUT using factory login username and password.
Receiver sDoC Procedure
Unintentional emissions of the OCR220 shall be performed on the module when it is installed in the Wabtec OCU. The end product is tested as a complete assembly with module installed. Performance is evaluated at the lowest, middle, and highest receive frequencies and evaluated against Part 15.109 using the 2.15dBi Omnidirectional antenna. Conducted emissions are performed using the conducted antenna port test per Part 15.111.
1. The EUT, when powered on, immediately enters receive mode. Commands to change RX frequency are required to complete the evaluation of the end product in receive mode.
2. Configure receiver to lowest frequency (command rx 217) 3. Perform radiated/conducted emissions testing 4. Repeat steps 2,3 at the middle frequency (command rx 219) 5. Repeat steps 2,3 at the highest receive frequency (command rx 222)
Wabtec shall generate a Supplier’s Declaration of Conformity sDoC declaring conformance of the unintentional radiator (receiver emissions) to FCC standards.
Wabtec is to provide instructions for RF exposure information to end users from page 11.
Transmitter Conducted Emissions Assessment
1. Attach a spectrum analyzer to the EUT Transmit Antenna port. Ensure proper attenuation is present for +33dBm without sustaining damage. Spectrum analyzer should be configured for the same RBW, VBW, and Sweep Time, Start, and Stop frequencies as the Part 90 and Part 15 FCC Test Data results published in the OCR220 reports.
2. Configure transmitter power to +33dBm (command pwr hi) 3. Configure transmitter to lowest frequency (command tx 217) 4. Key the transmitter (command key) 5. Record the results for Conducted TX 217MHz.
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OCR220: Module Integration Guide 6. Analyze the results to ensure that no new conducted spurious emissions exist, and that no existing spurious emissions are greater than the values obtained in the modular test reports. 7. Repeat steps 3, 4, 5, 6 at the highest frequency (command tx 222)
Transmitter Radiated Emissions Assessment
1. This testing must be performed in an Anechoic Chamber. A spectrum analyzer should be configured for the same RBW, VBW, and Sweep Time, Start, and Stop frequencies as the Part 90 and Part 15 FCC Test Data results published in the OCR220 reports. Radiated Emissions tests are performed with both vertical and horizontal polarizations and 360-degree turntable. The original unintentional radiated emissions results are repeated with the OCR220 Module installed in the OCU Host.
2. Terminate the Transmitter antenna port using a 50-ohm load with a minimum power handling capability of 2W.
3. Configure transmitter power to +33dBm (command pwr hi) 4. Configure transmitter to lowest frequency (command tx 217) 5. Key the transmitter (command key) 6. Record the results for Conducted TX 217MHz. 7. Analyze the results to ensure that no new conducted spurious emissions exist, and that no
existing spurious emissions are greater than the values obtained in the modular test reports. 8. Repeat steps 3, 4, 5, 6 at the highest frequency (command tx 222)
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Documents / Resources
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GE MDS OCR220 Radio Module [pdf] User Guide DS-OCR220 E5, MDS-OCR220 E5, MDSOCR220 ds ocr220, OCR220 Radio Module, OCR220, Radio Module, Module |