You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither SPIE nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the SPIE website.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print format on
SPIE.org.
Abstract
A generalized optical communication link is illustrated in Fig. 2.1. The information to be transmitted to the receiver is assumed to exist initially in an electrical form. The information source modulates the field generated by the optical source. The modulated optical field then propagates through a transmission channel such as an optical fiber or a free-space path before arriving at the receiver.
The receiver may perform optical processing on the incoming signal. The optical processing may correspond to a simple optical filter or it may involve interferometers, the introduction of additional optical fields, or the use of an optical amplifier. Once the received field is optically processed it is detected. The photodetection process generates an electrical signal that varies in response to the modulations present in the received optical field. Electrical signal processing is then used to finish recovering the information that is being transmitted.
Online access to SPIE eBooks is limited to subscribing institutions.