RDR - 10

Question 1

Describe the operation of the following: Continuous Wave (CW)

Answer 1

• A CW radar transmits continuously and simultaneously listens for target echoes.
• Typically used for fire control, the CW radar illuminates the target, the return echo is received by either the missile or another receiver which send guidance commands to the missile.

Question 2

Describe the operation of the following: Over The Horizon (OTH)

Answer 2

• Use of the HF portion of the EMS allows the operators
  long ranges without the requirement for huge power.
• The most common type of OTH radars use skywave or
  “skip” propagation, in which shortwave radio waves are
  refracted off the ionosphere.
• radio signals transmitted at an angle into the sky will be refracted towards the ground by the ionosphere

Question 3

Describe the operation of the following: Low Probability of Intercept (LPI)

Answer 3

• Designed to be difficult for an ESM suite to intercept, by using methods to reduce peak power.
• This includes:
  – Increased signal integration
  – Wider Frequency BW
  – Increased antenna gain
  – Increased antenna sensitivity, low power ouput
• Alternatively, frequency manipulation methods can be used:
  – Frequency Hopping
  – Frequency Modulation CW (FMCW)

Question 4

Describe the operation of the following: Sea Based X-Band (SBX)

Answer 4

• Used by US Defence Department Ballistic Missile Defence System
• Is a self propelled, floating, mobile active electronically scanned
  array EW radar capable of detecting, tracking targets and vectoring defensive assets.
• Operates in X Band : 8 – 12 GHz

Question 5

Describe the operation of the following: Digital Wave forming

Answer 5

• New electronically scanned arrays allow wave forming to be controlled by software and advanced processors.
• This results in increasingly agile radar beams.
• The result is new techniques are now available to
  overcome some of the traditional radar parameter
  compromises e.g. blind speeds vs Maximum Theoretical Range.