ComBlock COM-1826, Manual, Page: 1 / 18

COM-1826 TDRSS SPREAD-
SPECTRUM MODEM
Key Features

TDRSS spread-spectrum modem comprising
o
Demodulator with two input types:
GbE LAN/SDDS-formatted input
stream or RF input.
o
Modulator with baseband or RF output.

BPSK and SQPN spread-spectrum modulation

Convolutional/Viterbi error correction: K=7
Rate ½

Programmable 1023- (forward command link)
or 2047-chip (return mode 2 link) periodic I and
Q Gold codes

Programmable bit rates from 1 to 150 Kbits/s
on each channel. Two independent bit
synchronizers to acquire and track each channel
bit stream.

120-bin parallel code search for fast code
acquisition. False code lock prevention.

Built-in Bit Error Rate measurement for PRBS-
11 test sequences.

Demodulation performances: within 1.5 dB
from theory at threshold Eb/No of 2 dB.

Demodulated bits encapsulated in UDP frames
and sent out to the LAN. Support for IGMPv2
multicast addressing.

Monitoring:
o
Receiver lock, Carrier frequency error,
SNR

ComScope –enabled: key internal signals
can be captured in real-time and displayed on
host computer.

90VAC – 264VAC power supply

Options:
o
1-3 receivers per 1 RU chassis
o
Modulator with RF output
o
Demodulator RF input
For the latest data sheet, please refer to the ComBlock
web site: http://www.comblock.com/download/com1826.pdf .
These specifications are subject to change without notice.
For an up-to-date list of ComBlock modules, please
refer to http://www.comblock.com/product_list.html .
MSS • 845-N Quince Orchard Boulevard • Gaithersburg, Maryland 20878 • U.S.A.
Telephone: (240) 631-1111 Facsimile: (240) 631-1676 www.ComBlock.com
© MSS 2016 Issued 11/27/2016