Radar and ARPA Manual

1 Basic radar principles

1.1

Introduction

The word RADAR

is an

acronym derived from

the

words Radio

Detection

and Ranging.

In the

United King-

dom

it was

initially referred

to as

radio direction

finding

(RDF)

in

order

to

preserve

the

secrecy

of its

ranging

capability.

The scientist Heinrich Hertz, after whom

the

basic

unit

of

frequency

is

named, demonstrated

in 1886

that

radio waves could

be

reflected from metallic objects.

In

1903

a

German engineer obtained

a

patent

in

several

countries

for a

radio wave device capable

of

detecting

ships,

but it

aroused little enthusiasm because of its very

limited range. Marconi, delivering

a

lecture

in 1922 ...