Experimental research on the MRC diversity
reception algorithm for UV communication
LI GUO,
1,
*DEDAN MENG,
2
KUNLUN LIU,
2
XIDONG MU,
2
WEILUN FENG,
2
AND DAHAI HAN
3
1
Key Lab of Universal Wireless Communications, Ministry of Education, P.O. BOX 63, Beijing University of Posts and Telecommunications,
No. 10 Xitucheng Road, Beijing 100876, China
2
School of Information and Communication Engineering, Beijing University of Posts and Telecommunications, Beijing 100876, China
3
Institute of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, China
*Corresponding author: guoli@bupt.edu.cn
Received 3 March 2015; revised 20 April 2015; accepted 21 April 2015; posted 29 April 2015 (Doc. ID 235550); published 26 May 2015
Ultraviolet (UV) communi cation is an emerging communication met hod with non-line-of-sight, anti -inte rfer-
ence, and anti- interception capabilities, along with high flexib ility and reliability. Herein , the maximum ratio
combining (MRC) dive rsity reception algorith m for a UV communication system is studied. Simulation and
experimental results indicate that single and multiple outputs are useful and achieva ble, with an obvious diver-
sity gain, and the MRC diversity reception algorithm can reduce the system bit error rate more effectively than
the equal-gain combining method . The simulation and experimental results are analyzed, and the differences
between them are discussed. These results provide guideli nes for UV communi cation system design and
implement ation.
© 2015 Optical Society of America
OCIS codes: (060.4510) Optical communications; (060.2605) Free-space optical communication.
http://dx.doi.org/10.1364/AO.54.005050
1. INTRODUCTION
Although common communication methods play an impor-
tant role in military communication, their disadvantage s
cannot be ignored. For example, wireless communication
methods such as radio and microwa ves allow easy eavesdrop-
ping, interference, and destruction, and wired communication
requires the infrastructure to be installed in advance, which
is not suitable for flexibility or quick reaction in military
operations.
Ultraviolet (UV) communication is an emerging method,
whereby data are transmitted by using the scattering UV light
in the atmosphere. It provides an ideal means for tactical
communication [
1,2], owing to its non-line-of-sight (NLOS)
communication, anti-interference, anti-interception, flexibility,
and reliability.
Compared with other opt ical communication methods [
2],
UV communication is NLOS communication. On the other
hand, UV communication has such disadvantages as the fierce
inter-symbol interference and the multipath fading. Recently,
the study of UV communication has focused on the channel
model [
3–5], channel noise measurement, impact of UV filters
on the communication system, digital filtering and noise-
reduction processing on the receiver [
6], and modulation
and demodulation design and realization [
7]. However, few
studies have been performed to enhance the UV system using
space diversity technology. Single input and multiple output
(SIMO) technology is a useful method for attaining the diver-
sity gain [
8,9]. The combination of multiple input and multiple
output technology and UV comm unication is examined in [
10]
but without regard to the diversity reception algorithm and rel-
ative experiments. The equal-gain combining (EGC) algorithm
can obtain diversity gain from the results of theoretic research
and experiment in [
11] but without considering the UV chan-
nel differences between different receivers. The maximum ratio
combining (MRC) diversity reception algorithm for the UV
communication system is studied in this article. This algorithm
is adopted because it can compensate the channel differences
between each photomultiplier tube (PMT) receiver and,
thereby, yield a large output power and high UV communica-
tion system quality. Simulation results and UV system offline
experimental results indicate that the algorithm can reduce the
system BER more effectively than the EGC receiving method.
The remainder of the paper is organized as follows. The
NLOS UV communication system model and geometry struc-
ture, along with the MRC diversity reception algorithm,
are presented in Section
2. Section 3 des cribes the simulation
schematics and results. The system experiments are provided
in Section
4, and an analysis of the experimental results is
presented in Section
5. Section 6 concludes the paper.
Throughout this paper, the following notations are used:
vectors are denoted by boldface lower-case letters; matrices are
denoted by boldface upper-case letters.
5050
Vol. 54, No. 16 / June 1 2015 / Applied Optics
Research Article
1559-128X/15/165050-07$15/0$15.00 © 2015 Optical Society of America