UPTEC F 16039
Examensarbete 30 hp
Juli 2016
Audio quality perception of
SCIP encrypted voice transmission
over low quality radio links
Anton Sundin
Teknisk- naturvetenskaplig fakultet UTH-enheten
Besöksadress:
Ångströmlaboratoriet Lägerhyddsvägen 1 Hus 4, Plan 0
Postadress:
Box 536 751 21 Uppsala
Telefon:
018 – 471 30 03
Telefax:
018 – 471 30 00
Hemsida:
http://www.teknat.uu.se/student
Abstract
Audio quality perception of SCIP encrypted voice
transmission over low quality radio links
Anton Sundin
Tactical radio communications used in military applications has strict requirements regarding security and has to be operable in
rough environments in which there may be disturbances and disruptions on a radio link. The performance of the Secure Communication
Interoperability Protocol (SCIP) operating in an asynchronous communication network with various levels of packet loss is investigated and found inadequate mainly due to problems with cryptographic synchronization between the transmitting and receiving units. The introduction of additional counter data to each data packet remedies this problem and allows the receiving units to fill the holes left by packet losses with filler packets, maintaining synchronization. The audio quality can then be measured using the Perceptual Evaluation of Speech Quality (PESQ) algorithm.
Measurements are performed in an emulated radio link with a configurable packet loss ratio developed by Saab. The results show that parts of SCIP can be used alongside the counter solution without impacting the audio quality. The insertion of filler packets is shown to have a positive effect on the audio quality, while aggregation of packets to conserve transmission data rate is shown to have a negative effect.
ISSN: 1401-5757, UPTEC F16039 Examinator: Tomas Nyberg Ämnesgranskare: Ping Wu Handledare: Anders Gunnar
