KState Channel Modeling Hardware

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K-State Channel Modeling Hardware
Quick Reference Guide
Main Components
This board contains most of the components needed
for basic channel modeling, including mixers, a
summer, and an attenuator. These parts are
described below. External signals, measurement
equipment, cables, and various frequency-specific
parts like lowpass filters may have to be added
depending on the experiment.

• Mixers The board provides two general-purpose
  diode-ring mixers, with LO (L), IF (I), and RF
  (R) ports. When used for frequency conversion,
  the mixer needs about 7 dBm of LO power. When
  used for BPSK modulation as in the block diagram,
  the data should be input on the IF port. Signals
  at any port should not exceed 1 Volt or 13 dBm
  (DC or AC).
• Power Splitter/Summer The power splitter can be
  used either to split an RF (bandpass) signal at
  port S into two identical signals at ports 1 and
  2 (each about 3.5 dB weaker than the original),
  or to sum/add two bandpass signals at ports 1, 2
  together into port S. In the block diagram below,
  it is used for the latter.
• Step Attenuator The HP 355D, 355C step
  attenuators are cascaded together to allow
  attenuation of up to 132 dB in 1 dB steps. Never
  exceed 5 V or 27 dBm (DC or AC) at any connector.

Overview

• The K-State channel modeling board contains a
  collection of hardware designed to support
  various experiments in RF communication systems
  design.
• The hardware consists of two mixers, a summer,
  and a step-attenuator set. It covers IF through
  RF frequencies in the range of 100 kHz to 400
  MHz.
• With suitable external test equipment and coax
  cabling, it can be used in different experiments,
  including modeling a BPSK system with additive
  noise and variable path loss between the
  transmitter and receiver (yielding different
  signal to noise ratios). The diagram below shows
  the connections needed for this particular case.

Block Diagram of BPSK Channel Model
Rev 1.0, 03 July 2006, WBK