SATELLITE COMMUNICATIONS

Datum Systems' latest satellite modem implementation represents state of the art enhancements to the popular PSM-4900 series of modems at the industry's lowest price. The new PSM-500 series incorporates all of the features of the PSM-4900, and adds 8PSK and 16QAM modulation modes, a standard Reed-Solomon and IBS multiplexer and higher data rates. The multiplexer's overhead channels provides the capability for orderwire, AUPC and Remote Modem Control to every modem. The PSM-500 series is available in IF versions for 70 MHz, I40 MHz and L-Band applications.

To provide capabilities consistent with customer needs, the PSM-500 may be purchased in 3 upgradeable versions or "Feature Sets", the M505, M511 and M523. Each offers a combination of modulation modes and data rates as shown below designed to match the needs of various users without paying for features not needed. In addition a user can upgrade a modem from one version to another at a very nominal cost when requirements change.

• The M505 is designed as a direct replacement for the PSM-4900 modems. It's data rate and modulation modes are almost the same, plus it has a built-in IBS Multiplexer and Reed-Solomon capability. If the requirement is to add to existing systems using QPSK modulation and either Viterbi, Reed-Solomon or TPC then this is the right modem.
• The M511 fits the requirements of users who need higher data rates up to 10 Mbps, and/or 8PSK with Trellis Code modulation. The built in Reed-Solomon allows it to operate in the normal 8PSK, TCM, Reed-Solomon with Viterbi at Rate 2/3 without anything additional needed. This is a good general purpose modem able to meet the needs of Teleports, users whose carriers require 8PSK to minimize bandwidth, and those transmitting video signals.
• The M523 adds data rates up to 20 Mbps and 16QAM modulation. This modem can provide wideband outbound signals for large Star Networks, or a large channel point to point.

Upgrades from one version to another are accomplished by software/firmware loaded into the modem via a new USB connection on the modem rear panel.

There are currently two hardware options available for the PSM-500 series: TPC FEC cards and Ethernet Interface Cards. The TPC is a plug in card to the main modem board and can be either a 4k block Turbo Product Codes FEC (as in the PSM-4900) or a newer 16k block Turbo Product Codes FEC with higher performance (backward compatible with the PSM- 4900). The Ethernet interface can be either the current "SDMS" type card or a new Satellite Network Interface Processor, or "Snip", which is in development now.

PSM-500 Series Feature Matrix

Common Features:

• Programmable modulation modes.
• Programmable receive acquisition/tracking range.
• Typical DSP acquisition time of 315 mseconds at 9.6 kbps QPSK, 71 mseconds at 64 kbps QPSK.
• Viterbi and Reed-Solomon FEC standard, TPC optional. BER vs. Eb/No performance within 0.3 dB of theoretical. 10-7 BER at 6.0 dB Eb/No (2.8 dB with TPC, 3.5 dB with Reed- Solomon codec).
• DDS transmit and receive frequency setting in 1 Hz increments.
• Programmable Interface type.
• Low power, light weight 1 U case.
• Built-in IBS Multiplexer with overhead channel, AUPC and Remote Modem Control.
• Built-in BER Test Set.
• DDS setting of transmit and receive data rates from 1.2 kbps to 20 Mbps 8 User stored and recallable configurations. Automatic Recovery of stored configurations. in 1 bps increments.
• Viterbi FEC codec programmable to rate 1/2, 2/3, 3/4, 5/6, 7/8 and disabled.
• Wide AGC range.
• Full front panel control with keypad, LCD display and LED status.
• Fully programmable from either front panel or remote command without jumpers.
• Built-in 1:1 Redundancy.
• Designed to use internal or external G.703 and Ethernet interfaces.
• 8 User stored and recallable configurations. Automatic Recovery of stored configurations.