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P300H

P300 Modem Installation and Operating Handbook

Page 133

8.3

PARTIAL INSERT AND MULTIDESTINATIONAL WORKING

Partial Insert is only available if the Extended D/I feature is available (standard on P300-TCM). In a typical
scenario, there may be a 2048kbps incoming carrier, containing say 8 timeslots (512kbps) for this
destination. When set to 

All

 the full 2048kbps has to be received and passed to the terrestrial. When set

to 

Partial

, only the 8 timeslots for this destination are selected and inserted onto the insert mux bearer

avoiding overwriting 

all the data

 on the bearer.

This technique can be applied to lower rate carriers also. Imagine four destinations which require mesh
connectivity for simplicity say at 384kbps (6 x 64kbps, although asymmetric operation up to any rate is
possible). Each site has a modulator transmitting 1152kbps (3 x 384kbps), and three demodulators
receiving the 384kbps from the other sites. The satellite bandwidth requirement is for four 1152kbps
carriers, not twelve 384kbps carriers (ie the same aggregate rate, but possibly lower overall bandwidth
when carrier spacing is taken into consideration):

A single T1 or E1 bearer is looped through three modems, one operating as Tx/Rx, and two others
in Rx only. In this example we will assume it is a T1 PCM bearer.

The Tx data for all destinations arrives at the single Tx modem in each site on the T1 bearer in 18
timeslots. Note that the ability to re-order the Tx & Rx timeslots means the data can be in 

any

timeslots and in any order.

Each of the four sites transmits a 1152kbps (3 x 384kbps carrier) and all four destination sites
receive the three carriers from the other destinations.

At each site all three modems are configured for Rx Partial Insert, and the data for all but this site
is discarded leaving a 384kbps to be inserted onto the looped T1 bearer by each Rx modem. In
this way the data from each site for this destination can be re-inserted into the original timeslot
from which the Tx data was dropped.

Without

 Partial Insert if each Rx modem inserts 

all the received data

 (18 timeslots) onto the T1 bearer,

then the second Rx modem could just about insert its 18 timeslots without stamping on the 6 timeslots for
this destination from the first Rx modem. However Rx modem 3, still has 18 timeslots to insert, but 12 of
the timeslots on the T1 bearer now contain receive information from Rx modems 1 & 2, and so Rx modem
3 cannot insert all its data without losing data from another destination. The traditional alternative without
Partial Insert is to use separate bearers for each Rx modem and a DACCS to sort our the data, but it's
lower cost and less equipment to configure and maintain if the DACCS is not required at all ! 

Partial Insert becomes 

mandatory

 for multidestinational working when the total receive data at any one

destination exceeds the capacity of the PCM bearers. 

One final note: The P300 can provide multidestinational operation at aggregate carrier rates below 1544
kbps using the IBS overhead, but 

with four backward alarms.

 So multidestinational working down to

64kbps between nodes become practical (ie you don't have to use the 96kbps IDR overhead on the links
to get multidestinational backward alarm facilities).

Summary of Contents for P300-VSAT

Page 1: ...se Datacom LLC 1 Wheaton Road 1012 E Boal Avenue Witham Essex CM8 3TD England Boalsburg PA 16827 U S A Phone 01376 515636 Int 44 1376 Phone 814 466 6275 Int 1 814 Fax 01376 533764 Fax 814 466 3341 htt...

Page 2: ...5 2 VISUAL INSPECTION OF EQUIPMENT 38 5 3 INTERFACE OPTIONS 38 5 4 IF INTERFACE 38 5 5 POWER UP 38 6 MENU SYSTEM 39 6 1 INTRODUCTION 39 THE 1 MINUTE GUIDE TO FRONT PANEL OPERATION 39 6 2 MENU STRUCTUR...

Page 3: ...Modulator AUPC TOLERANCE Menu 73 6 6 24 Change Tx Modulator AUPC COMMS LOST ACTION Menu 73 6 6 25 Change Tx Rx ESC AUX BA Menu 74 6 6 26 Change Tx Rx ESC Aux BA DEFINE IDR Menu 75 6 6 27 Change Tx Rx...

Page 4: ...SAT Menu 103 6 10 8 Change User Opt Operation ALARMS Menu 104 6 10 9 Change User Opt DISPLAY Menu 104 6 10 10 Change User Opt AGC Output Menu 104 6 11 CHANGE TIME DATE MENU 105 6 12 MONITOR MENU 106 6...

Page 5: ...ES OF RS N K 134 8 5 NOTES ON DATA RATES SYMBOL RATES 135 8 6 DETERMINING EXACT MAXIMUM ESC BAUD RATES 136 8 7 CLOSED NETWORK PLUS ESC 137 8 7 1 Overhead Rates 137 8 7 2 Closed Network Plus ESC via th...

Page 6: ...RE SOON 182 APPENDIX C4 ASYMMETRIC LOOP TIMING 182 APPENDIX C5 UPGRADE AVAILABLE 182 APPENDIX C6 FEATURES NOT AVAILABLE 182 APPENDIX D REMOTE M C 183 REMOTE M C PROTOCOL 183 Summary 183 Character Form...

Page 7: ...ensure that the following points are observed 1 The equipment MUST BE OPERATED WITH ITS COVER ON AT ALL TIMES If it is necessary to remove the cover for any reason then you must ensure that the cover...

Page 8: ...ent is classified in EN 60950 as a pluggable equipment class A for connection to the mains supply As such it is provided with a mains inlet cord suitable for use in the country of operation In normal...

Page 9: ...relay outputs designed to connect to station monitoring system The modems also provides a complete remote Monitor Control M C port allowing the status to be remotely monitored and the unit controlled...

Page 10: ...e addition of extra hardware It might appear that the words Feature and Option are used interchangeably In practice however we have attempted to use Options to refer to functions which always require...

Page 11: ...IESS 308 P1348 Emulation 32 64kbps Aux data in place of one both IDR audio ESC PRBS Tester 8 8 Internal Bit Error Rate Tester BERT overhead modes only 8PSK TCM 8 8PSK with E rate Trellis Code Modulati...

Page 12: ...8 1PPM internal frequency clock reference with external station clock input 8 CCITT INTELSAT V 35 scramblers for closed network operation with additional two modes for compatibility with FDC and Link...

Page 13: ...multiplying V 35 self synchronising scrambler L A high rate async ESC channel in IBS SMS overhead achieving 2400 Baud with a 64kbps carrier requires IBS SMS feature standard on P300 IBS and above L A...

Page 14: ...s ESC interface eg 2400 Baud at 64kbps in standard IBS SMS mode any Baud rate for Closed Net Plus ESC Again typically used for distant end M C via the overhead Aux Port provides a front panel selectab...

Page 15: ...es a more configurable version of Closed Net Plus ESC where the overhead varies from the standard 16 15 6 7 In minimum overhead mode the user sets the required ESC Baud rate and the overhead is scaled...

Page 16: ...at operator set intervals including average worst case Eb No average worst case estimated user BER average worst case estimated uncorrected BER and the buffer fill state The logged performance monitor...

Page 17: ...on the front panel of previous products has been moved to the rear panel and is now combined onto the Async ESC connector a D type connector instead of the difficult to obtain 8 pin din audio type co...

Page 18: ...female which accepts a 1 10MHz signal either a square wave of 1V p p eg a G 703 para 10 synchronising clock or a sinusoid at a power level of 0dBm or greater An alternative Station Clock signal at RS...

Page 19: ...m a PC or the printing of the units traffic log to a serial printer PC terminal emulator If the Monitor AGC option is fitted it provides I Q and symbol clock outputs to monitor the receive constellati...

Page 20: ...d so could not be incorporated whilst maintaining CE compliance If this style of connector is required then an external adaptor cable must be used If the G 703 option is fitted then in addition to RS4...

Page 21: ...C PCM 32K ADPCM AUX OUT DPLL BLANK PCM FRAME GEN Rx BUFFER Tx PLL Rate Convert DEFRAMER From FEC Demodulator FRAMER INTERLEAVER To FEC Modulator RS DECODER RS ENCODER INTERNAL BER TESTER Tx FIFO DROP...

Page 22: ...C 8 I I 8 Q Q DAC Tx PLL SYNTH TURBO SEQ SEQ TURBO VIT TCM VIT TCM 50 MHz SAW BPF ADC DIGITAL DEMOD 10 5dB AMP AMP INPUT MATCH LPF AGC DOWN CONVERT MIX SWITCHED LPF BANK P P Rx PLL SYNTH INTEGRATOR Fr...

Page 23: ...Network Resolution of 1 bps Rate Rate Rate I I Uncoded Rate E E BPSK min 4 8k 7 2k 8 4k 9 6k max 1250k 1875k 2187k 2500k QPSK OQPSK min 9 6k 14 4k 16 8k 19 2k mix 2 5M 3 75M 4 375M 5 0M 8PSK TCM min...

Page 24: ...urn loss 18 dB typical External reference Clocking only 1kHz 10MHz in 1kHz steps See Station Reference Clocking Frequency 10 MHZ 0 dBm 1 dB Modulator Specifications Output Power Level 0 to 25 dBm cont...

Page 25: ...qualised INTELSAT IESS compliant BER Performance In all cases met in the presence of two adjacent carriers each 10 dB higher than the desired carrier with V 35 scrambling These figures meet or exceed...

Page 26: ...disable Transmit input clock plesiochronous includes full asymmetric rate operation Internal reference 1 ppm DCE External timing clock DTE interface only Station reference see below Station Reference...

Page 27: ...of frame sync INTELSAT Reed Solomon Codec Custom Features Format Concatenated Reed Solomon outer codec to IESS 308 310 Code Rate Default n k t 126 112 7 depth 4 automatically switching to 225 205 10...

Page 28: ...4 5 6 8 10 12 15 16 20 24 30 see Extended D I Feature below Extended Drop Insert Feature Timeslot Re ordering Selected timeslots may be independently re ordered on both Tx and Rx paths Timeslot ID Mai...

Page 29: ...nd of the overhead IDR Option IDR ESC Audio Interface Two 32 kbps ADPCM channels 4 wire 600 6 7 dBm to 16 dBm software programmable in 0 1 dB steps Backward Alarms Outputs Four form C relays Inputs Fo...

Page 30: ...om the main interface This is compatible with a P400 Series modem fitted with P1448 card or a P230 Modem with a P1348 card alternatively Drop Insert can be used at the distant end to place the two 32k...

Page 31: ...rs Slew rate limit comms loss action freeze max or nominal power Ancillary features Automatic logging of distant Eb No and local AUPC delta power at user controlled intervals in traffic log Automatica...

Page 32: ...aintaining impedances L Band inputs outputs are passively split combined outside the units Offline unit tri states data outputs mutes Tx carrier Mechanical 1 U chassis 355 mm deep Weight 7 lbs 3 kg Po...

Page 33: ...nditions FEC Viterbi Rate 128 kbps QPSK TX 140 0000 MHz RX 140 0000 MHz V 35 Scrambling Input Level 60 dBm Spec limit R1 2 Coding Ideal BPSK QPSK Rate 3 4 Rate 7 8 P300H P300 Modem Installation and Op...

Page 34: ...s FEC Sequential Rate 64 kbps QPSK TX 140 0000 MHz RX 140 0000 MHz V 35 Scrambling Input Level 40 dBm Spec limit R1 2 Coding Ideal BPSK QPSK Rate 3 4 Rate 7 8 P300H P300 Modem Installation and Operati...

Page 35: ...Coding Ideal BPSK QPSK Rate 3 4 Rate 7 8 Test Conditions FEC Sequential Rate 2048kbps QPSK TX 140 0000 MHz RX 140 0000 MHz V 35 Scrambling Input Level 50 dBm P300H P300 Modem Installation and Operatin...

Page 36: ...TCM Rate 2048 kbps 8PSK TX 70 0000 MHz RX 70 0000 MHz V 35 Scrambling Input Level 45 dBm Ideal BPSK QPSK TCM plus RS TCM no RS RS Concatenated Reed Solomon Outer Coding 219 201 P300H P300 Modem Insta...

Page 37: ...P300H P300 Modem Installation and Operating Handbook Page 37 P300 Modem Series Error Probability versus Eb No Turbo Codec...

Page 38: ...products this unit is fitted as standard with an interface that is AN INTEGRAL PART OF THE MODEM main board DO NOT TRY TO REMOVE THE CARD Customer specific interface options are available but these r...

Page 39: ...again just press the YES Key ie you don t have to reselect the same option to get past the menu just press YES Options displayed with a colon eg 1 Status switch to another screen or subsequent menu bu...

Page 40: ...unusual settings eg IBS with 7 8 rate FEC If anything is found a warning is displayed and can be masked by pressing YES These are only warnings and after you mask each displayed warning you may contin...

Page 41: ...timeout of remote M C activity expires REMOTE M C Configure Remote Local SEE PAGE 5 SEE PAGE 6 USER OPTIONS Alarm Thresholds Operation Display Analog o p AGC OUTPUT Option Monitor AGC 2 digit numeric...

Page 42: ...summary Inner FEC Reed Solomon summary Aux channel summary Service options summary ESC audio levels Baseband Framed Symbol rates AUPC Remote reporting setting Descrambler summary Buffer size MF slip P...

Page 43: ...CHANNEL Main data path ESC Channel Aux Channel BER PATTERN 2 11 1 2047 2 15 1 2 20 1 INT BER TESTER Option PRBS Tester Off Channel Pattern Results Control BER TESTER RESULTS Display of Sync No Sync Sy...

Page 44: ...ffer multiframe slip Thin route spoof X 50 AIS G 732 Spare bits SATELLITE BER Estimate IBS MF Period Carrier ID s Backward Alarm map 50 75Ohm IF IBS MF Period 4 digit numeric entry ms CARRIER ID S 3 d...

Page 45: ...async channel Maximum Custom SYNC AUX O H USE ASYNC ESC MODE P230 Compatible Custom All available after Aux RATE DISPLAY Display of rates available with the assigned overhead Max async ESC rate Aux ci...

Page 46: ...ock RX OUTPUT BEARER CLOCK SOURCE Satellite Tx clock in Internal Station clock Rx Baseband Mode Continuous data Insert mux Rx Bearer Loop Generate STATION CLOCK FREQ Entry of station clock frequency 1...

Page 47: ...llite Modem Status Display no faults Status Display Tx Rx faults Configuration Summary Traffic Status Summary Rx Status detailed Tx Status detailed Demod status detailed User selection of default scre...

Page 48: ...occurred CARR Mute 1 1 Muted by 1 for 1 logic CARR Mute Ext Muted by external signal on alarms connector CARR Mute RTS Carrier set to RTS controlled and interface RTS line is off CARR Mute Flt Muted d...

Page 49: ...affic Status and a Detailed Demodulator Status Any Unit Faults override Tx Rx Traffic Summary and displays the fault message such as When a unit fault is displayed it takes over the whole of the Tx Rx...

Page 50: ...EMODULATOR STATUS This screen shows the estimated Eb No This is the composite Eb No including framing overheads as used by INTELSAT when specifying modem performance figures The BER is the final USER...

Page 51: ...up to be checked and looks for unusual combinations of configuration parameters eg IBS with rate I FEC coding multiple scramblers selected Check does not prevent operation with any configuration it is...

Page 52: ...ite data to provide whatever ESC rate is selected When this mode is selected there is also the option to provide a Backward Alarm facility Closed Net Plus ESC also has the advantage that at rates abov...

Page 53: ...compatible with other closed network equipment such as the Paradise P200 and closed network equipment from other vendors PLUS ESC The modem adds the minimum possible overhead to the satellite data dow...

Page 54: ...s local equipment if the distant end Rx fails for any reason eg local Tx failure or distant Rx failure The proportion of the overhead assigned to the ESC drops slightly 68 to 65 so the overhead may in...

Page 55: ...r P1348 P1448 voice data mux card used often in SNG applications The menu dialogue for this continues in section 6 6 6 on page 60 6 6 4 Change Tx Rx Baseband CONTINUOUS Menu Selecting CONTINUOUS DATA...

Page 56: ...specified The screen above shows groups of eight timeslots selected 1 3 4 5 17 16 15 23 although any combination is possible The selection system works by toggling timeslots or groups of timeslots int...

Page 57: ...AS signalling mode active T1 ESF T1 D4 Timeslots 10000000 Note that in G 732 mode TS0 is never replaced with idle code even if it is part of the Drop selection and Idle is selected If the modem is set...

Page 58: ...in use with the least significant bit of each timeslot being used for signalling in frames 6 12 D4 or 6 12 18 24 ESF of the terrestrial multiframe When this option is selected the Drop Insert data is...

Page 59: ...RBS are active then the Modem will maintain the timeslot identity by using the satellite TS32 multiframe where possible unless N the number of dropped inserted timeslots falls into the category of Odd...

Page 60: ...entity of the timeslots will not be maintained as with normal IDR 6 6 6 Change Tx Rx Baseband OTHER Menu If the IDR option is fitted standard on P300 IDR and above then the modem can generate a 64kbps...

Page 61: ...backup clock as used when INTERNAL is selected to maintain the carrier distant demodulator lock and if a framing overhead is active the Backward Alarm Aux and ESC channels INTERNAL The Modem outputs a...

Page 62: ...tes it does not require the Rx rate to be higher than the Tx or the rates to be in any way related Finally and only for those with inquisitive minds why does it state earlier This option is only of an...

Page 63: ...100Hz resolution The unit will reject a frequency which falls outside the ranges stated and will prompt the user to re enter the value Once complete the user should press the YES key to accept the ne...

Page 64: ...hoices are between NONE uncoded VITERBI if Viterbi FEC option fitted SEQUENTIAL if Sequential FEC option fitted TCM Trellis Code Modulation if the 8PSK TCM feature is available Rate 2 3 only Turbo Tur...

Page 65: ...turn to the Change Tx Modulator menu This list can contain up to 31 different rates but initially only the following are defined others will be added later Screen Description Exact code rate Delay bit...

Page 66: ...byte are in error However when the error rate exceeds the correctable level unlike other FEC schemes which degrade gracefully Reed Solomon fails dramatically Once the error correction threshold is pa...

Page 67: ...i Sequential or No FEC IDR 1544 kbps 225 205 10 2048 kbps Other rates 126 112 7 IBS or All rates Closed Net Note When interworking with NEC modems in TCM mode and IBS framing NEC have chosen to use In...

Page 68: ...ors degrading performance Other This allows non standard scrambler operation to match the configuration of other non standard equipment which leads onto the following menus Pressing 1 2 3 or 4 toggles...

Page 69: ...ontrolled by the Sig Valid In the RTS line on a V 35 DCE interface see interface card details in appendix A for line names for other interfaces No alarm is raised when the Tx carrier is muted by the R...

Page 70: ...rt option reverses the ordering of the pairs of Tx data symbols from the FEC encoder to the modulator The Normal option is compatible with other manufacturers BPSK equipment The Invert option ie rever...

Page 71: ...ll AUPC mode As with MON DIST above it uses the ESC channel to collect Eb No information from the distant modem but in addition it varies the Tx power within the constraints provided to maintain a spe...

Page 72: ...nditions being considered a bonus It is it not normally necessary to set the minimum delta power to any figure other than zero otherwise any beneficial gain in Eb No caused by good atmospheric conditi...

Page 73: ...PC TOLERANCE Menu This sets a tolerance window on the monitored Eb No The AUPC will only attempt to restore the monitored Eb No to the target Eb No when the monitored Eb No moves outside the tolerance...

Page 74: ...or async ESC and allocate different parts of the overhead to each port In Closed Net Plus ESC the ESC channel is already defined to use as much of the overhead as possible and the Aux channel is not a...

Page 75: ...art 8 data bits no stop or parity At 9600 Baud with 8 bits char there are a maximum of 960 async characters per second 9600 10 start 8 bits stop 960 async characters per second requires 9 x 960 sync b...

Page 76: ...interface the single Data line used for the oversampled INTELSAT ESC on the Async ESC connector cannot provide a synchronous interface If selected the Aux port operates synchronously and varying amoun...

Page 77: ...u allows the overhead assigned to the ESC port to be determined P230 COMP The standard 20 32nds of the overhead is allocated to the ESC and this is compatible with earlier products such as the P230 P2...

Page 78: ...ging the ESC rate overhead ESC assignment which the overhead then adjusts to provide The screens are as follows Each of the XXX fields can display the following uses for that part of the overhead and...

Page 79: ...ESC Baud Rate is the maximum continuous rate the ESC channel will support the ESC channel must be set to a standard async Baud rate equal or below this figure using the Async ESC menu selection The Au...

Page 80: ...ESC async character format may be edited by pressing 1 or 2 to select 7 or 8 bits and 3 4 or 5 to select No parity Even parity or Odd parity respectively Note that as described in the last paragraphs...

Page 81: ...nu This instructs the Modem make an internal link between the ESC port and the remote M C port It must be set specifically for the end of the link the modem is located at When either of these options...

Page 82: ...des for the Audio ESC channels but may also be used when generating a 64kbps IBS carrier comprising of 2 x 32kbps ADPCM audio channels only or a 128kbps comprising of 2 x 32kbps ADPCM audio channels p...

Page 83: ...ier we are receiving does not correspond to the destination allocated backward alarm channel 1 The Rx fail signals from the modems receiving the carriers from all the other destinations including this...

Page 84: ...pendent are Baseband Insert timeslot selection only if Drop Insert active Buff Clk Rx Buffer size clocking mode Demod IF Frequency Sweep control Note that setting Rx Tx even momentarily copies the Rx...

Page 85: ...lly LOOP TERR The PCM bearer at the input to the Drop Mux is looped to the Insert Mux If this bearer should fail no clock or AIS the modem will switch temporarily to Generate Internally so that the Rx...

Page 86: ...r this destination is selected from the total receive data The incoming data from the satellite is labelled as timeslots 1 N NOTE this labelling bears NO RELATION to the terrestrial timeslots from whi...

Page 87: ...or arbitrary values such as 2500k or 4321k Values down to 1kHz not 1MHz are accepted a frequency of 0 indicates there is no station clock When a Station Clock is present the Modem will use it in pref...

Page 88: ...he normal bearer looped from the Drop Mux fails and the unit auto generates a backup bearer onto which to insert the Rx data Note that this screen does not display a Tx option as it is the failure of...

Page 89: ...internal reference for backups If the Station Clock is at a different frequency to the Rx Data rate the Rx PLL converts the Station Clock to the correct rate to drive the Rx data towards the terrestri...

Page 90: ...ble under CHANGE USER OPT OPERATION TRANSFER BUFFER MF SLIP A second option is available to automatically force the buffer to its mid position whenever the receive traffic switches from failed to OK T...

Page 91: ...Change Rx Demod IF FREQUENCY Menu See Change Tx Rx Modulator IF Frequency Menu on page 63 6 7 9 Change Rx Demod MODULATION Menu See Change Tx Rx Modulator Modulation Menu on page 63 6 7 10 Change Rx D...

Page 92: ...nt Please note the following 1 Increased sweep width proportionally increases the carrier acquisition time 2 With low data rates and wide sweep widths ie wider than the recommended carrier spacing it...

Page 93: ...re acquire the carrier even with further minor variations in Rx carrier frequency without it sweeping into a false lock If you are attempting to do this when you have the Demod correctly locked you c...

Page 94: ...option for each available control signal of ignoring the signal or raising a Traffic Fault alarm if the interface control line goes Off CARD SPECIFIC Some interfaces such as 64 kbps G 703 have specif...

Page 95: ...too many contiguous spaces the G 703 receiver fails to recover the clock properly as there are no incoming pulses for a while and it causes data errors HDB3 and B8ZS are both methods of ensuring that...

Page 96: ...ines IGNORE ALL All the control lines are ignored the dialogue ends here ACTIVE CONFIGURE The three following screens are presented in turn allowing each line to be individually controlled The line na...

Page 97: ...ay take local control at any time 6 9 1 Local Control TAKE AWAY GIVE AWAY Selection Under SERVICE FACTORY PARAMETERS REMOTE M C the following menu is provided TAKEAWAY When selected the operator can s...

Page 98: ...trol is only possible if the protocol is not Off and control has been selected as Remote on the Change Remote M C menu INTERFACE The options available here are RS232 or RS485 RS232 is only usable for...

Page 99: ...his is the Eb No as displayed on the screen whenever the demodulator status is displayed BUFFER SLIP The operator may also instruct the modem to raise the deferred alarm if the interval between buffer...

Page 100: ...ACTION This option is similar to BER action above except it specifies how the modem is to handle the detection of AIS the Alarm Indication Signal all ones INTELSAT specify the required actions as the...

Page 101: ...s returned by the distant equipment when it receives an errored CRC ie the incoming E Bits represent the error rate at the far end of this modems outgoing G 732 link Effectively the error rate on the...

Page 102: ...output error rate of the RS Decoder based on the number of uncorrectable words passed by the decoder PRBS The real BER as measured by the PRBS tester whether it be in the ESC or Aux channel or the mai...

Page 103: ...ame length at these specific rates Options are Adjust Normal or Don t Adjust Default ADJUST THIN ROUTE SPOOF This interestingly named option is to allow full connectivity of a PCM bearer to be spoofed...

Page 104: ...ault 0 FAULT MODE A value from 0 15 where 0 is Normal Default 0 6 10 9 Change User Opt DISPLAY Menu The options are STATUS SCREEN This selection are covered in the section Status Screen Display on pag...

Page 105: ...12 06 97 OK yes 1 Time adjust 2 Date Adjust Change Time Date Menu 6 11 CHANGE TIME DATE MENU This menu is self explanatory and allows the user to set the correct time and date so that events added to...

Page 106: ...decoder from the FEC unless operating uncoded The difference between this and the To FEC figure shows the improvement due to the Inner FEC BER on FAW An estimate of the USER BER based on the count of...

Page 107: ...carrier and the earth station These were named Station ID Carrier ID Spare ID More recent issues just say reserved for uses such as If the demod is receiving a suitable carrier then the ID s from the...

Page 108: ...ctively the lower line shows the target Eb No along with its tolerance window and the current AUPC delta power If the delta power reaches the preset limit either up or down then it is prefixed with ei...

Page 109: ...th contact fax and phone numbers and e mail addresses VIEW CONFIG This screen allows the configuration of the modem to be displayed After selecting between Tx Rx Interface Common and Remote M C subseq...

Page 110: ...e log to be viewed on the LCD The Up Arrow and Down Arrow keys allow the operator to scroll through the list of logged events Each entry is logged with it s time and date PRINT This allows the log ent...

Page 111: ...ith separate Drop Insert bearers by the use of a twin G 703 terrestrial interface The method of BER measurement can be selected by Change User Opt Operation Terrestrial Rx Insert BER AUPC DELTA POWER...

Page 112: ...modem try the cables For the remote loopback to function when this loopback is selected the clocking must be configured in a mode where it would work if the loop were made in the cables Rx clocking m...

Page 113: ...o looped RS L The data is looped after the Reed Solomon Encoder interleaver back into the RS Deinterleaver decoder providing a local loop only The Tx data continues to be transmitted and the Rx data f...

Page 114: ...RS CORRECTIONS DISABLE This option allows the corrections being made by the RS decoder to be inhibited without the removal of the RS overhead This allows the true effect of the Reed Solomon codec to b...

Page 115: ...continuously using a 1 minute sliding window When Auto Logging of the BER Tester results is enabled the tester executes a test for the user set BER Auto Log period 1 9999 minutes and records both the...

Page 116: ...e is used to determine the overhead added to the main data allowing the minimum possible overhead to be added ie the minimum bandwidth to be used to provide the Async ESC Baud rate required When the E...

Page 117: ...ly available if the Custom Features feature is available standard on P300 TCM Custom framing is based on either IBS or IDR formats and custom framing provides the following advantages Based on IBS A v...

Page 118: ...le AUTOLOG of PRBS results is active YES is displayed To be able to manually select the BERT mode auto logging of the BER result must be disabled by either setting the Autolog period to zero Main Log...

Page 119: ...to a maximum of 27 7 hours BER The calculated BER over the entire duration of the test ie average over test period It is displayed as follows When there are more than 100 errors the exact BER is disp...

Page 120: ...dropped to say 4 of the main data channel implying that reducing the bits available to measure the BER by 20 will have no effect on the validity of the BER reading The argument for the Internal BERT...

Page 121: ...er is therefore 911 from the main menu So the key sequence Main 9 1 1 will kill the Tx carrier whatever screen was left active on the display NOTE This is an OFF only selection to switch the carrier o...

Page 122: ...rnal temperature can be monitored on the TEST PSU TEMP menu A Unit Warning deferred alarm will be activated if ever the internal temperature reaches within 3 degrees Centigrade of the operating limits...

Page 123: ...rd alarms for Multidestinational IBS Minimum overhead mode where the overhead scales to provide any ESC requirement at any data rate IDR This leads to variants on standard IDR framing again explained...

Page 124: ...following screen is displayed If either the Backward Alarm facility or the TS32 Multiframe have been disabled then this menu is skipped NORMAL A single backward alarm operates as normal FOUR ALARMS T...

Page 125: ...As the exact overhead format is calculated based on your ESC requirement for two Modems to calculate the same overhead usage and therefore interwork the following parameters must be the same at both e...

Page 126: ...ESC channels operate in 16kbps ADPCM mode allowing both audio ESC s to fit into 32kbps The 32kbps for FAS Back Alarms 8K sync ESC channel is transmitted first followed by 32kbps defined for Audio ESC...

Page 127: ...ervice definitions but the data rate at the terrestrial port is actually 2048kbps When selected instead of the unit inserting extra IBS SMS framing on to the data ie 6 7 it uses the similar G 732 fram...

Page 128: ...selected a timeslot edit screen is displayed as follows This screen allows the operator to change the order of the transmitted timeslots The screen above shows groups of timeslots 1 15 and 17 31 swop...

Page 129: ...LIGN FOR RX A terrestrial G 732 frame format is acquired and is aligned within the IDR frame to allow the receive equipment to re order the timeslots if so set Other than aligning the terrestrial fram...

Page 130: ...han one clock in the system and a buffer is required to absorb the difference between the two clocks Typically data is placed into the buffer with one clock and removed with another thus causing a gra...

Page 131: ...s enough for the Doppler shift from 1 satellite hop on current INTELSAT satellites For 2 x Doppler shift 4ms is required Set the Tx Rx Clock modes as follows to use the clock listed Clock from the int...

Page 132: ...equired for any application If Lc is the local clock accuracy e g 1 x 10 9 and Rc is the remote clock accuracy e g 1 x 10 11 and Ms is the Minimum slip period in days e g 40 days then the required Ple...

Page 133: ...Each of the four sites transmits a 1152kbps 3 x 384kbps carrier and all four destination sites receive the three carriers from the other destinations At each site all three modems are configured for R...

Page 134: ...t so this intermittent reduction in error correcting capability is minimised Note that in theory error correction codes 100 90 5 and 200 180 10 are equivalent they can correct 5 bytes in 100 and 10 i...

Page 135: ...26 5 5 and 4 in 64 6 25 respectively with similar overheads 126 112 12 5 64 56 14 3 but with interleaving decoder delays reduced from 5632 to 3104 bits 156ms to 85ms at 32kbps If using Sequential FEC...

Page 136: ...the timeslot ID for an Odd value of N or if RBS signalling is active then only 7 out of 8 of every TS16 are available for ESC as TS16 has to carry the CAS MF unique word or pack byte every 8th frame...

Page 137: ...1 19 0 62 0 59 19200 Baud n a n a 50 10 5 4 76 2 5 2 38 1 25 1 19 38400 Baud n a n a 100 20 10 5 4 76 2 5 2 38 The formula for deriving the overhead rate is moderately complex and relies on many diff...

Page 138: ...ich follows the Custom option from the Tx Rx Service selection screen Main Data Rate Based On TS32 MF Backward Alarm No of Back Alm Overhead Mode 32kbps IBS Normal User choice One Min O H 32kbps IBS N...

Page 139: ...ll be compatible with other manufacturer equipment with the same number of timeslots selected 8 Configure the receive path similarly if Rx Tx is active then only the timeslots need selecting Note the...

Page 140: ...omplete 7 If you have selected an Odd value of N the unit will prompt TS Identity over satellite 1 Normal maintain 2 Don t maintain If you select Normal maintain the unit will provide TS identity main...

Page 141: ...rom the two differing V 35 camps schematic written description was a background pattern dependent error rate in the order of 1 x 10 Note that as the 8 background error rate is pattern dependent there...

Page 142: ...Linkabit Paradise P200 series closed net Scrambler on BPSK requires P300 Tx Spectrum invert Paradise P230 IBS SMS Uses synchronous IBS scrambling so V 35 type not an issue FDC SM290 SM2900 Viterbi V 3...

Page 143: ...s through the asynchronous ESC channel which is carried over the satellite multiplexed with the main data channel For AUPC to operate an async ESC channel must be defined and on the P300 this is avail...

Page 144: ...arate upper and lower Tx power limits are set along with a slew rate limit if it is felt that additional limits to prevent rapid power variations are required By manipulating the upper and lower power...

Page 145: ...eature Change Log Autolog The AUPC delta power can also be output on the uncommitted analog DAC output if the Monitor AGC option is fitted again see uncommitted analog DAC output value 5 in Appendix E...

Page 146: ...reporting rate For Closed Net Plus ESC our suggestion would be to include the optional Backward Alarm as this is a very useful feature and set the Baud rates as high as possible without either exceedi...

Page 147: ...han the target but will increase the power if the Eb No falls below target To maintain a fixed Eb No set this as the Target Eb No set the Max power to the maximum increase you are allowed and set Min...

Page 148: ...d in the same bandwidth the resolution bandwidth of the analyser this is the same as E N s o Within the demodulator each Symbol is converted back into the Transmitted Bits For BPSK each Symbol represe...

Page 149: ...y as it compensates for these parameter changes b o When comparing BER performance for different Modulation FEC schemes against E N the b o plotted E N already accounts for the changes in Carrier Nois...

Page 150: ...Code rate expressed as n k t 126 112 7 112 Information bits 126 Decoded 219 201 9 201 Information bits 219 Decoded 225 205 10 205 Information bits 225 Decoded 126 112 7 0 51 dB 219 201 9 0 37 dB 225 2...

Page 151: ...6 0 4 74 6 2 5 01 6 4 5 27 6 6 5 53 6 8 5 78 7 0 6 03 7 2 6 28 7 4 6 53 7 6 6 77 7 8 7 01 8 0 7 25 8 2 7 49 8 4 7 72 8 6 7 95 8 8 8 19 9 0 8 42 9 2 8 64 9 4 8 87 9 6 9 10 9 8 9 32 10 0 9 54 10 5 10 09...

Page 152: ...ll interfaces also have the facility to disable the outputs either by making the outputs high impedance or by relay switching enabling one of a parallelled pair to drive the outputs without line conte...

Page 153: ...its outputs are tri state the standby LED on the front and the Hi Z LED on the rear should illuminate on one modem 5 Connect the data interfaces in parallel and configure the two units alike Suitable...

Page 154: ...dem as loading the software requires a processor reset and will affect the traffic To access the Boot Menu power the unit up whilst holding in the MAIN key and the following menu will be displayed Opt...

Page 155: ...r re boots The first reboot with a new main code the unit performs a checksum test on each bank displaying the results as follows Finally when the checksums are verified the processor jumps into the n...

Page 156: ...in the field 1 1 OPERATION The standard RS422 V 35 and RS232 interface does not require any resistor packs to be unplugged for 1 1 redundancy operation HOWEVER the G 703 option has a switch to set the...

Page 157: ...e connecting cables extend beyond 10m As an estimate assume the maximum rate halves as the distance doubles ie 5Mbps to 20m 2 5Mbps to 40m etc The input clock data phase is selected automatically repo...

Page 158: ...te assume the maximum rate halves as the distance doubles ie 5Mbps to 20m 2 5Mbps to 40m etc The input clock data phase is selected automatically reporting a Data Marginal warning whenever it has to s...

Page 159: ...bps to 40m etc NOTE this is a synchronous RS232 interface if you need an asynchronous interface please contact the factory The input clock data phase is selected automatically reporting a Data Margina...

Page 160: ...1 cards AMI or HDB3 In coded ie non AMI modes the modem will display a Data Marginal warning whenever a line code violation is detected For T1 cards a choice of line lengths is also given to allow the...

Page 161: ...edance if power is removed allowing the units 1 1 partner to carry the traffic The normal input impedance switches to whichever one is on line with the standby input at high impedance Installation not...

Page 162: ...X 21 unless you set the clocking correctly The Rx Clock Menu is used to set the source of the single clock from the modem as either Satellite Internal or Station Clock Do not select Tx Clk In as this...

Page 163: ...e set to return Rx data in time with the single Tx Clock by also selecting Tx Clock In NO OTHER COMBINATIONS WILL WORK The maximum data rate is 10Mbps over good quality twisted pair screened cable but...

Page 164: ...allowing software selection of the interface RS422 V 35 RS232 G 703 control lines in non G 703 modes RTS etc in and line code and length in G 703 modes With the appropriate pins grounded the modem rec...

Page 165: ...Out ST 114 21 8 LK 7 DATA CIRCUIT FROM MODEM RX 8 Clock Out RT 115 4 17 LK 4 8 Data Out RD 104 16 3 LK 5 COMMON LINES 8 Ground to Activate Eurocom D 14 n a Do Not Connect 12 20 n a 8 Signal Ground SG...

Page 166: ...rectly at this rate Min Req Signal Description centre tap of 25 pin Link to ground transformer A B DATA CIRCUIT TOWARDS MODEM TX 8 Clock Data In 24 11 LK 3 DATA CIRCUIT FROM MODEM RX 8 Clock Data Out...

Page 167: ...Pin D Female pin compatible with SA bus Pin Signal Name name RS232 Direction Name RS485 SA Bus Paradise 1 Shield Gnd Shield Shield Gnd Shield Gnd 2 SRR 3 Master B to modem SSD RX B 4 Slave B from mod...

Page 168: ...second hop to a more distant station would be the Local end again local because they are the end of that specific link nearest the M C computer Pin numbers for Async ESC ports in the table above are s...

Page 169: ...ows Unit 1 Unit 2 Pin 1 Screen Pin 1 circuit ground Pin 2 Pin 3 On Line signal 2 1 Pin 3 Pin 2 On Line signal 1 2 Pin 6 Pin 7 Fail signal 2 1 Pin 7 Pin 6 Fail signal 1 2 Keep this lead as short as pra...

Page 170: ...y 14 Not connected 15 Ground To externally inhibit the Transmit carrier either apply a TTL CMOS low signal to pin 7 or short pin 7 to ground for example with an external relay closure All relay contac...

Page 171: ...ation monitor Rx signal quality 14 Rx I channel eye 7 Rx Q channel eye 15 Rx symbol clock 13 Ground RS422 Differential Station Clock Input 4 Station Clock a 11 Station Clock b 13 Ground RX CONSTELLATI...

Page 172: ...nnels both ESC and Aux channels ie high rate async ESC INTELSAT low rate ESC cannot be used simultaneously In IDR Mode this port is not used as when the IDR option is fitted separate ESC and Aux ports...

Page 173: ...Tx ESC Data in 14 8 8 Tx ESC Data in B n c 32 8 Rx ESC Clock out A Rx ESC Clock out 33 8 Rx ESC Clock out B n c 15 8 8 Rx ESC Data out A Rx ESC Data out 16 8 8 Rx ESC Data out B n c 46 8 Tx ESC Octet...

Page 174: ...ux port is not used In IBS modes the Aux port can be set to both INTELSAT using TS32 bit 1 and Sync modes selectable to use any of TS16 TS32 bits 1 5 8 TS48 In both modes a clock is provided and the p...

Page 175: ...from the front panel of 7dBm to 16dBm Audio is encoded as 32kbps ADPCM or 16kbps ADPCM in some custom modes The Audio ports may be used in two applications In IBS modes if set to emulate a P1348 P144...

Page 176: ...hen connected to 0V The Rx summary fault is an open collector output 0V Fail open collector OK From the front panel the backward alarm inputs BA x can be set as follows E Ext A Auto Rx fail O OK Menu...

Page 177: ...However as most of the processing is provided by the T1000 ASIC the optional hardware is limited to The Sequential FEC a plug in Xilinx chip or module The Turbo codec a plug in module The Viterbi TCM...

Page 178: ...owing hardware and software mechanism Needless to say for any specific feature to be used the equipment needs both the hardware to be fitted and the software to have that feature enabled Hardware The...

Page 179: ...RES STANDARD The letters shown represent the features that are permanently enabled in the equipment Standard features even if not required by the current configuration To determine if any of the featu...

Page 180: ...he features a Feature Code will be provided to make the features permanent If you are unable to contact Paradise Datacom for some reason use one of the 5 day Feature Tests to give you all the features...

Page 181: ...ackward alarms H Aux IBS variable rate synchronous Aux channel IDR 32 64kbps in place of one both audio J P1348 emulation Emulation of P1348 P1448 cards popular in SNG applications Includes generation...

Page 182: ...modem configuration after timeout eg to re use it then use the configuration memories to store the current configuration before it times out and is changed and recall it after the features are availa...

Page 183: ...cters there are no such constraints on the other characters in the message Electrical Interface Both protocols require a 4 wire plus ground interconnection between equipments Signals are at RS485 leve...

Page 184: ...4 to request a standard ACK add 80H 128 to 10 10 request an extended ACK to this message Body From 0 to 248 characters resulting in a maximum message length of 255 characters Asterisk An ASCII charact...

Page 185: ...Body NAK One character an echo of the instruction sent ACK Where no response is expected ie a write message one character an echo of the instruction sent Where a response is called for ie a query mes...

Page 186: ...23 14 ack Change 1 UnitCfgQry V0 61 to unit 24 1 UnitCfgRd Query The parameters which affect both Tx Rx paths including user alarm thresholds and all user settings etc current config or config memori...

Page 187: ...e internal cards software 6 UnitInfoRd V0 61 from unit 18 UnitInfoQry Status 7 SAFChgWr to unit 51 14 ack Change Enter an unpgrade code there is no direct corresponding read other than V1 76 SAFStat 7...

Page 188: ...ssages 11 Ack extended V0 61 from unit 1 Note Instruction codes used for SA bus messages are as specified above 30H SA bus instructions 70 7F are not used Note on First Available column Items marked h...

Page 189: ...s follows Prompt Unit Fault Any unit fault or Tx traffic fault ie Tx summary alarm Prompt Traffic Fault Any unit fault or Rx traffic fault ie Rx summary alarm Deferred Fault Function unchanged from no...

Page 190: ...right down to 16kbps below which with the minimum 512bits of processing memory the delay increases again above 32ms The data rate used to determine the processing memory size is the receive rate inclu...

Page 191: ...muted when the corresponding ACU block signal is active It will not however immediately switch the traffic over to the other modem in the 1 for 1 pair ie not switch the traffic to the other antenna as...

Page 192: ...changed which of the two components is delayed with respect to the other between the earliest of the P400 series modems and ongoing P400 P300 production If you experience difficulty interworking in O...

Page 193: ...t repeatability is relatively poor 4dB but on any one unit it will be consistent and so show trends accurately 1 Rx Eb No Level Scaled at 1V per 2dB with extremes of 0V 0dB and 10V 20dB and a 0 1dB re...

Page 194: ...r Software versions 2 12 Valid only when the AUPC feature is active this provides an output of the local power adjustments in made in order to maintain the distant Eb No Scaling is 0V 25dB 10V 25dB wi...

Page 195: ...kbps transmitted by use of a separate CAS Multiframe sequence in TS16 48 Timeslot ID Maintenance which is the facility to maintain the identity of individual data streams when multiplexed together int...

Page 196: ...ttern itself is 2 1 32767 bits long and runs throughout the frame 15 Scrambling is however disabled for TS0 TS32 otherwise the distant end could never find the frame sync then TS32 multiframe sync in...

Page 197: ...ly the idle code from one of the other dropped timeslots If the Timeslot ID is maintained you should consistently get the PRBS back in this same subset or single timeslot Bear in mind that without TS...

Page 198: ...ing channel for TS0 nor TS16 as TS0 is reserved for the Frame Alignment Word and TS16 carries the signalling for the other timeslots Robbed Bit Signalling RBS Robbed bit signalling is a technique used...

Page 199: ...el Associated Signalling to be transferred across the satellite link between E1 PCM bearers within the IBS satellite overhead The P300 equipped with the Extended D I feature standard on P300 TCM uses...

Page 200: ...2 CAS 8 5 TS 32 CAS 8 TS 32 TS 32 6 TS 32 CAS 8 CAS 24 CAS 24 7 CAS 56 CAS 56 CAS 56 CAS 56 8 TS 32 CAS 32 CAS 8 CAS 16 9 CAS 24 CAS 24 CAS 72 CAS 72 10 TS 32 CAS 8 TS 32 TS 32 11 CAS 88 CAS 88 CAS 88...

Page 201: ...e is trouble with the link in the other direction Additional Features Paradise products Where many IDR carriers exist between sites the Audio ESC on the second and subsequent carriers are not required...

Page 202: ...played message For Unit Fault Check UNIT FAULTS section For Warning Check UNIT WARNINGS section For Tx Fault Check TX TRAFFIC FAULTS section For Tx Warn Check TX TRAFFIC WARNINGS section For Rx Fault...

Page 203: ...unit has muted the Tx IF output U CM CM TF Tx carrier muted to prevent transmitting an incorrect signal An external 10MHz station reference may be used as the synthesizer reference so if the station r...

Page 204: ...is used to indicate the terrestrial equipment is functioning properly The line switching off may be user set to cause this fault or be ignored Change Terr Int Control Lines See note 5 Opt Opt Tx Fault...

Page 205: ...seband is set to use T the Drop mux in G 732 mode or 2048k IBS G 732 0 overhead mode and when set by the user to process CRC s Change User Opt Operation Terrestrial PCM Bearer CRC Process If CRC sync...

Page 206: ...eive downstream equipment but could be due to the modem Rx output failing Check the modem Rx path indicates OK Check the Rx data output from the modem is connected to the downstream equipment Tx Warn...

Page 207: ...sion Change Rx Demod Spect Inv Rx Fault De interleaver sync lost The Demod can lock to the carrier and the inner FEC decoder to the demodulated data However T TA TC SB RF the Reed Solomon De interleav...

Page 208: ...RBS Rx Fault Final data is all ones AIS The final customer data after demodulation error correction deframing and descrambling is all T TA SB ones This is normally used to indicate an upstream equipm...

Page 209: ...fault In such a circumstance the modem temporarily generates a PCM bearer onto which the Rx data can be inserted to preserve the Rx traffic See notes 6 9 Rx Fault Insert bearer AIS generating See abo...

Page 210: ...NSMIT path ie from our modem Tx output though the Tx chain through the satellite and then through the whole distant end Rx path or even further downstream has failed and is returning an alarm This may...

Page 211: ...iption of the dialogue under Change Rx Buff Clk Rx Clock to determine which signal the PLL uses as a backup clock Rx Warn No clk ref source now int The reference specified for the PLL which generates...

Page 212: ...rm Change User Opt Thresholds Eb No This may be used as an advance warning of service degradation Rx Warn Rx BER below user threshold The final Bit Error Rate is worse than the user threshold set for...

Page 213: ...from the Doppler Buffer to the Insert Mux has slipped full or empty This should never occur in operation contact factory Rx Warn DISTANT Eb No below threshold The DISTANT modems Receive Eb No ie this...

Page 214: ...separate 3 Line code setting For P1431 32 cards check the switch on the card itself For P1440 41 42 cards which are configured from the front panel check with Change Terr Int Electrical then reselect...

Page 215: ...ear the memory by powering up the unit while holding in the NO key but you have to hold the key in until the unit gives its normal three beeps 9 If you wish to use Drop Insert and pass the incoming sa...

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