Personal Earth Station

 

 

 

 

 

 

 

 

 

 

 

 

 

    Contents

 

     Topic

Page No.

 

 

 

 

1.

Introduction

3

2.

PES Cards Identification

7

3.

PES – Normal Operation

10

 

Operating modes

 

 

       Normal Mode

12

 

       Installation Mode

12

 

       Ranging Mode

13

 

       Diagnostic Mode

14

4.

LED – Display List

14

 

       Remote Port card LED Codes

15

 

       Normal Startup Sequence

15

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1.  Introduction:-

 

The Personal Earth Station (PES) is a complete data and voice telecommunications terminal supporting two-way access via satellite to centralized computer and telephone exchange facilities. In addition, some models of the PES can also receive video signals when equipped with an optional satellite television signal receiver.

Given below is a typical link from Earth station to the VSAT.

 


 

 

 


The PES-8000 Indoor Unit front and back view are show on the next page.

 

INDOOR UNIT: The 7-1/4" high PES Model 8000 indoor unit has a front panel nameplate reading: PERSONAL EARTH STATIONTM

. Note that the nameplate does not include the letters "DIU/O." The rear panel is marked with the 8000 model number.

 

OUTDOOR EQUIPMENT: RF Unit, with 1.0M, 1.2M, 1.8M, or 2.4M quick repoint antenna. For sites designated for video reception, as a general rule the antenna is 1.8M or larger. The Outdoor Equipment is shown on the next page.

 

 


 

 

 


 

 


2.   PES CIRCUIT CARD IDENTIFICATION: -

PES 8000 indoor units provide port card slots. Generally, these port cards provide the interface to customer data or voice equipment.

 

DATA PORT CARDS (DP)

The DP provides the interface to the user’s digital equipment. The DP card provides a single RS-232 serial data port interface. The Hub downloads software to the DP for the specific digital communications protocol required.

 

 


   

 

 


 

 

 


 

 

 

 


TURBO PORT CARD (TP)


 The TP also provides interface to the user’s digital equipment and has two or four serial data communications links. Two of these ports are always RS-232 (built-in PLC). The next two data ports (plug-in PLC) may have the following

 


interface standard: RS-232, modem backup style RS-232, V.35, RS-422 or other standards or capabilities as developed.

 

 


 

 

 

PES MODEL OR TYPE SPECIFIC CIRCUIT CARDS

The signal the PES receives from the satellite must be down converted, demodulated, and decoded. In addition, the PES must achieve receive synchronization with the signal. The PES must determine the proper timing for the transmit signal and must encode and modulate signal to be transmitted.

 

INTERMEDIATE FREQUENCY MODULE (IFM)

The intermediate frequency module (IFM)  accepts the received mixed outroute and video signals from the RF Unit, tunes to the appropriate receive frequency, down converts the signal, if necessary despreads the signal (required for the spread Quietroute signal),demodulates and decodes the outroute signal, and sends the processed results to the IOC chip on backplane. The IFM provides transmit filtering and modulation of the transmit signal. The IFM also provides monitor and control functions for the PES including an interface for the site commissioning computer (CONFIG connector), storage of commissioning parameters in EEPROM, and LED display of PES status.

 

 

 

 

 

3.  PES - NORMAL OPERATION

 

GENERAL

The PES is designed for unattended operation, and once installed, tested, and initially started, no operator action is required under normal conditions. Except for servicing, indoor power should remain on at all times.

The RF Unit has no controls or indicators. The RF Unit health and status is displayed on the indoor unit LEDs. The PES Model X000 series indoor unit does have controls and indicators, but these do not require attention during normal operation.

The indoor unit power switch should remain on at all times during normal operation.

If the system is fully operational and running without any errors, the IFM  displays an alternating BLANK/BLANK. ([ ]/[ .]) status (looks like a flashing decimal point).

All the port cards after proper boot up will give BLANK/BLANK display also.

The normal boot up sequence for the port cards(viz. TPC & VDPC) is given below in details.

 


 

 

 

 

 


OPERATING MODES

 

The operational modes are: normal mode, installation mode, (COMM) ranging mode, and diagnose mode.

 

 

NORMAL MODE

In normal mode, the PES goes through the steps necessary so that the remote may carry traffic across the spacelink. Those steps are as follows:

·        Startup Initialization - the PES performs startup self tests, initializes hardware and communications links.

·        Outroute Acquisition - PES performs the processing required to find and begin receiving the outroute.

·        Transmit Frequency Lock - the PES performs the processing required to precisely tune the transmit frequency. The PES does not allow port card transmission until frequency lock is obtained.

·        Outroute Tracking - the PES receives the outroute and transmits inroute bursts on port card command. The PES transmits overhead and traffic bursts set at a "Ranged Power Level" and a "Ranged Timing Offset."

 

 

INSTALLATION MODE

In INSTALLATION mode, the PES goes through startup initialization and sets its spacelink receive equipment to receive on the programmed primary outroute frequency previously configured into the indoor unit. During installation mode the IFM LED state code is [1]. Installation mode provides an antenna-pointing signal (10 volts to 0 volts) at the RF Unit. An installer uses a voltmeter to observe this signal while refining the antenna aiming adjustment. Lower readings on the voltmeter indicate a strongly received signal. Specifically, a reading of:

 

 

·        5.0 to 10.0 volts indicates that the demodulator has not acquired the outroute. The voltage reading corresponds to the overall receive signal strength and is a function of the receive demodulator’s AGC value. A larger value indicates a higher AGC level, indicating a weaker outroute signal.

·         0.0 to 5.0 volts indicates that the demodulator has acquired the outroute. The voltage reading corresponds basically to the receive signal strength and is a function of the Eb /No (energy per bit to noise energy ratio). An Eb /No of 5.0 dB or less indicates a mediocre signal which is Displayed as a 5.0-volt reading. An Eb /No of 12.0 dB (or higher) indicates a high quality signal. The AGC v the demodulator acquires the signal, providing a clear indication of the remote’s receive status. The antenna pointing output is decreased about 0.4 volts per dB of signal strength (an antenna pointing output reading of 2.2 volts, for instance, indicates an Eb /No of 12 dB).

alue never actually reaches a 5.0-volt reading; the meter will jump when the antenna pointing is refined so that the signal is minimized (less than 3 volts, for example), it indicates that:

 

·        The PES receiver has locked onto an outroute.

·        The Ebi /No reading is at the highest value that can be attained by adjusting antenna pointing.

 

COMM (RANGING) MODE

The COMM (ranging) mode causes the PES to transmit ranging bursts which start at an "Initial Power Level" and an "Initial Timing Offset." An automatic process (automated ranging) or the Hub operator (manual ranging) measures the power and timing of these bursts as they arrive at the Hub. During ranging, adjustments are made to the transmit burst power and timing.

 

 

DIAGNOSE MODE

In the diagnose mode, a remote runs through an expanded set of self tests once and displays the results on the IFM seven segment LED. An installer typically puts a remote in diagnose mode to enter the site commissioning parameters with the portable computer, because a remote does not transmit while in diagnose mode.

 

IFM AUTO COMM - RECESSED SWITCH

The recessed AUTO COMM switch on the rear of the IFM is for customer use immediately after the antenna is repointed to a new satellite in an emergency repoint situation. Pressing the recessed switch using a toothpick or similar object interrupts data traffic and places the PES in COMM (ranging) mode, initiating a 10- to 30-minute autocommissioning ranging session which adjusts the site’s PES transmit power and timing for the new satellite. When the adjustments are finished, the port card display is [3]/[b.]. Pressing the recessed switch again returns the PES to normal mode. Do not press the recessed switch during normal installation commissioning. Instead, use the DIU Configuration Editor SWITCH function to select the desired PES mode including COMM (ranging) mode when needed.

 

 

4.  LED DISPLAY LIST

 

During normal operation for PES model X000 series, the indoor unit LED indication for the IFM, and port cards is a blank alternating with a blank dot. This indication looks like blinking decimal points, [BLANK]/[BLANK.]. When these normal indications are present, the PES is receiving the proper outroute signal from the Hub and is ready to transmit (or is transmitting) inroute signals to the Hub. When the PES is in other than normal operation (such as being reset, under self-test, in diagnose mode, in installation mode, in alarm mode, or other states

 

and conditions), the LED displays change from [BLANK]/[BLANK.] to an alphanumeric code. These alphanumeric codes are indicative of PES and network conditions, and thus provide troubleshooting information.

 

REMOTE PORT CARD LED CODES


 

 


NORMAL STARTUP SEQUENCE

 

As the PES is switched ON , the following displays are seen on the 7-segment display of the PORT CARDS.

 

·         LED spinning pattern - LED test.

·        1/2. - Port card is waiting for a poll from the IOC/IFM

·        8/2. - 8/4. - Port card is waiting to get into outroute sync. 8/4. indicates that a superframe header is being received, and regression to 8/2. indicates that the superframe header did not have the right carrier ID number.

 

·        8/E. - Port card is waiting for a broadcast of the RAM boot code from the hub. The broadcast occurs automatically (at time intervals configurable from the hub), or it can be forced via the VOC DLL CNTRL screen.

·        8/F. - Port card is receiving RAM boot code packets. This broadcast lasts about 15-20 seconds.

·        8/blank. - Port card received some RAM boot code packets but then quit receiving them. This comes up only if a packet was missed during the broadcast or the remote just got in sync during a broadcast and so missed some of the first packets. The card will wait for the broadcast again, and then will transition to 8/F. to receive the missed packets before proceeding to 5/h.

·        5/h. - Remote waits here until an RRD is received confirming the RAM boot code version.

·        7/1. - When a HIAM response is received, the port card progresses to this state and waits for 15 seconds or until network parameters are received. The

network parameters broadcast occurs automatically (at time intervals configurable from the hub), or it can be forced via the

VOC DLL CNTRL screen.

·        5/6. - Remote may wait here for a minute or so for the transmit phase lock loop to lock up.

·        5/8. - 5/9. - Card waits here to transmit HIAM messages to the hub.

·        7/2. - 7/3. - Port card is transmitting a code request to the hub.

·        7/4. - Port card is receiving user code packets. If not all are received, the port card will eventually go back to 7/2.

·         blank/blank. - Online state, user code is running

 

Please note that after booting, the Port Cards will show a display of BLANK/BLANK.

If any abnormal displays are seen, then the user will have to contact Central HUB for online help.