8 research outputs found
ΠΠΌΠΏΠΈΡΠΈΡΠ΅ΡΠΊΠΈΠΉ ΠΏΠΎΠ΄Ρ ΠΎΠ΄ ΠΊ ΠΎΡΠ΅Π½ΠΊΠ΅ ΠΏΠΎΠΌΠ΅Ρ ΠΎΡΡΡΠΎΠΉΡΠΈΠ²ΠΎΡΡΠΈ ΡΠΈΠ³Π½Π°Π»ΠΎΠ² ΡΠ°Π·ΠΎΠ²ΠΎΠΉ ΠΌΠΎΠ΄ΡΠ»ΡΡΠΈΠΈ
ΠΡΡΠΎΠΊΠ°Ρ ΡΠΏΠ΅ΠΊΡΡΠ°Π»ΡΠ½Π°Ρ ΡΡΡΠ΅ΠΊΡΠΈΠ²Π½ΠΎΡΡΡ ΡΠΈΠ³Π½Π°Π»ΠΎΠ² Ρ Π½Π΅ΠΏΡΠ΅ΡΡΠ²Π½ΠΎΠΉ ΡΠ°Π·ΠΎΠ²ΠΎΠΉ ΠΌΠΎΠ΄ΡΠ»ΡΡΠΈΠ΅ΠΉ ΠΎΠΏΡΠ΅Π΄Π΅Π»ΠΈΠ»Π° ΠΈΡ
ΠΈΠ·Π²Π΅ΡΡΠ½ΠΎΡΡΡ ΠΈ Π°ΠΊΡΠΈΠ²Π½ΠΎΠ΅ ΠΏΡΠΈΠΌΠ΅Π½Π΅Π½ΠΈΠ΅ Π² ΡΠ°Π·Π»ΠΈΡΠ½ΡΡ
ΡΠ°Π΄ΠΈΠΎΡΠ΅Ρ
Π½ΠΈΡΠ΅ΡΠΊΠΈΡ
ΠΏΡΠΎΠ΅ΠΊΡΠ°Ρ
. Π£Π½ΠΈΠΊΠ°Π»ΡΠ½ΠΎΡΡΡ ΡΠ²ΠΎΠΉΡΡΠ² ΡΠ°ΠΊΠΈΡ
ΡΠΈΠ³Π½Π°Π»ΠΎΠ² ΡΠ²ΡΠ·Π°Π½Π° Ρ ΡΠΎΡ
ΡΠ°Π½Π΅Π½ΠΈΠ΅ΠΌ Π½Π΅ΠΏΡΠ΅ΡΡΠ²Π½ΠΎΡΡΠΈ ΠΈΡ
ΡΠ°Π·Ρ ΠΏΡΠΈ ΡΠΌΠ΅Π½Π΅ ΠΈΠ½ΡΠΎΡΠΌΠ°ΡΠΈΠΎΠ½Π½ΡΡ
ΠΏΠΎΡΡΠ»ΠΎΠΊ Π½Π° Π΄Π»ΠΈΡΠ΅Π»ΡΠ½ΠΎΡΡΠΈ ΡΠΈΠΌΠ²ΠΎΠ»Π°. ΠΠΌΠ΅ΡΡΠ΅ Ρ ΡΠ΅ΠΌ Π΄ΠΎ Π½Π΅Π΄Π°Π²Π½Π΅Π³ΠΎ Π²ΡΠ΅ΠΌΠ΅Π½ΠΈ ΠΈΠ· Π²ΡΠ΅Π³ΠΎ ΡΠΈΡΠΎΠΊΠΎΠ³ΠΎ ΠΊΠ»Π°ΡΡΠ° ΡΠΈΠ³Π½Π°Π»ΠΎΠ² Ρ Π½Π΅ΠΏΡΠ΅ΡΡΠ²Π½ΠΎΠΉ ΡΠ°Π·ΠΎΠ²ΠΎΠΉ ΠΌΠΎΠ΄ΡΠ»ΡΡΠΈΠ΅ΠΉ Π½Π°ΠΈΠ±ΠΎΠ»ΡΡΠ΅Π΅ ΡΠ°ΡΠΏΡΠΎΡΡΡΠ°Π½Π΅Π½ΠΈΠ΅ ΠΏΠΎΠ»ΡΡΠΈΠ»ΠΈ ΡΠ°Π·Π»ΠΈΡΠ½ΡΠ΅ Π²Π°ΡΠΈΠ°ΡΠΈΠΈ ΡΠ°ΠΊ Π½Π°Π·ΡΠ²Π°Π΅ΠΌΡΡ
ΡΠΈΠ³Π½Π°Π»ΠΎΠ² ΡΠ°ΡΡΠΎΡΠ½ΠΎΠΉ ΠΌΠΎΠ΄ΡΠ»ΡΡΠΈΠ΅ΠΉ Ρ ΠΌΠΈΠ½ΠΈΠΌΠ°Π»ΡΠ½ΡΠΌ ΡΠ΄Π²ΠΈΠ³ΠΎΠΌ. ΠΠ΄Π½Π°ΠΊΠΎ ΡΡΠΎ Π΄Π°Π»Π΅ΠΊΠΎ Π½Π΅ Π΅Π΄ΠΈΠ½ΡΡΠ²Π΅Π½Π½ΡΠ΅ ΠΏΡΠ΅Π΄ΡΡΠ°Π²ΠΈΡΠ΅Π»ΠΈ ΠΊΠ»Π°ΡΡΠ° ΡΠΈΠ³Π½Π°Π»ΠΎΠ² Ρ Π½Π΅ΠΏΡΠ΅ΡΡΠ²Π½ΠΎΠΉ ΡΠ°Π·ΠΎΠ²ΠΎΠΉ ΠΌΠΎΠ΄ΡΠ»ΡΡΠΈΠ΅ΠΉ, ΠΎΠ±Π»Π°Π΄Π°ΡΡΠΈΠ΅ ΡΠ²ΠΎΠΉΡΡΠ²ΠΎΠΌ Π²ΡΡΠΎΠΊΠΎΠΉ ΡΠΏΠ΅ΠΊΡΡΠ°Π»ΡΠ½ΠΎΠΉ ΠΊΠΎΠΌΠΏΠ°ΠΊΡΠ½ΠΎΡΡΠΈ.
ΠΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½Ρ Π½Π΅ ΠΌΠ΅Π½Π΅Π΅ ΠΈΠ½ΡΠ΅ΡΠ΅ΡΠ½ΡΠ΅ ΡΠΈΠ³Π½Π°Π»Ρ ΡΡΠΎΠ³ΠΎ ΠΊΠ»Π°ΡΡΠ°, ΡΠΎΡΠΌΠΈΡΡΠ΅ΠΌΡΠ΅ ΠΏΠΎΡΡΠ΅Π΄ΡΡΠ²ΠΎΠΌ Π΄Π²ΠΎΠΉΠ½ΠΎΠΉ ΡΠ°Π·ΠΎΠ²ΠΎΠΉ ΠΌΠΎΠ΄ΡΠ»ΡΡΠΈΠΈ. ΠΡΠ΅Π΄ΡΡΠ°Π²Π»Π΅Π½Ρ Π°Π½Π°Π»ΠΈΡΠΈΡΠ΅ΡΠΊΠΈΠ΅ Π²ΡΡΠ°ΠΆΠ΅Π½ΠΈΡ ΠΈΡ
ΡΠΈΠ½ΡΠ΅Π·Π°, ΠΎΠ±ΠΎΡΠ½ΠΎΠ²Π°Π½Π° ΠΈΡ
ΠΏΡΠΈΠ½Π°Π΄Π»Π΅ΠΆΠ½ΠΎΡΡΡ ΠΊ ΠΊΠ»Π°ΡΡΡ ΡΠΈΠ³Π½Π°Π»ΠΎΠ² Ρ Π½Π΅ΠΏΡΠ΅ΡΡΠ²Π½ΠΎΠΉ ΡΠ°Π·ΠΎΠ²ΠΎΠΉ ΠΌΠΎΠ΄ΡΠ»ΡΡΠΈΠ΅ΠΉ. Π’Π°ΠΊΠΆΠ΅ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½Ρ Π²ΡΠ΅ΠΌΠ΅Π½Π½ΡΠ΅ ΡΠ²ΠΎΠΉΡΡΠ²Π° ΡΠ°Π·ΠΎΠ²ΠΎΠΉ ΡΡΠ½ΠΊΡΠΈΠΈ, ΡΠ΅ΠΊΠΎΠΌΠ΅Π½Π΄ΠΎΠ²Π°Π½Π½ΠΎΠΉ ΠΠ‘Π-R SM.328-11 Π΄Π»Ρ ΡΠΈΠ½ΡΠ΅Π·Π° ΡΠΈΠ³Π½Π°Π»ΠΎΠ² Ρ Π½Π΅ΠΏΡΠ΅ΡΡΠ²Π½ΠΎΠΉ ΡΠ°Π·ΠΎΠ²ΠΎΠΉ ΠΌΠΎΠ΄ΡΠ»ΡΡΠΈΠ΅ΠΉ, ΠΏΡΠΈΠ²Π΅Π΄Π΅Π½Ρ Π²ΡΠ΅ΠΌΠ΅Π½Π½ΡΠ΅ ΠΈ ΡΠ°ΡΡΠΎΡΠ½ΡΠ΅ ΡΡΠ°Π³ΠΌΠ΅Π½ΡΡ ΡΠΈΠ³Π½Π°Π»ΠΎΠ² Ρ ΠΌΠΈΠ½ΠΈΠΌΠ°Π»ΡΠ½ΡΠΌ ΡΠ΄Π²ΠΈΠ³ΠΎΠΌ Π² ΡΡΠ°Π²Π½Π΅Π½ΠΈΠΈ ΡΠΈΠ³Π½Π°Π»Π°ΠΌΠΈ Ρ Π΄Π²ΠΎΠΈΡΠ½ΠΎΠΉ ΡΠ°Π·ΠΎΠ²ΠΎΠΉ ΠΌΠ°Π½ΠΈΠΏΡΠ»ΡΡΠΈΠ΅ΠΉ. ΠΡΠ΅Π΄ΡΡΠ°Π²Π»Π΅Π½Ρ ΡΡΠ°ΠΏΡ Π°Π½Π°Π»ΠΈΡΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ Π²ΡΠ²ΠΎΠ΄Π° ΠΌΠΎΠ΄Π΅Π»ΠΈ ΠΏΠΎΠΌΠ΅Ρ
ΠΎΡΡΡΠΎΠΉΡΠΈΠ²ΠΎΡΡΠΈ ΡΠΈΠ³Π½Π°Π»ΠΎΠ² Ρ Π½Π΅ΠΏΡΠ΅ΡΡΠ²Π½ΠΎΠΉ ΡΠ°Π·ΠΎΠ²ΠΎΠΉ ΠΌΠΎΠ΄ΡΠ»ΡΡΠΈΠ΅ΠΉ ΠΏΠΎ ΠΏΠΎΠΊΠ°Π·Π°ΡΠ΅Π»Ρ Π²Π΅ΡΠΎΡΡΠ½ΠΎΡΡΠΈ Π±ΠΈΡΠΎΠ²ΠΎΠΉ ΠΎΡΠΈΠ±ΠΊΠΈ Π½Π° ΠΎΡΠ½ΠΎΠ²Π΅ ΡΠΌΠΏΠΈΡΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ ΠΏΠΎΠ΄Ρ
ΠΎΠ΄Π°. ΠΠΎΠΊΠ°Π·Π°Π½Π° ΠΎΠ±ΡΠ½ΠΎΡΡΡ ΠΏΠΎΠ»ΡΡΠ΅Π½Π½ΠΎΠΉ ΠΌΠΎΠ΄Π΅Π»ΠΈ Ρ ΠΈΠ·Π²Π΅ΡΡΠ½ΡΠΌ Π²ΡΡΠ°ΠΆΠ΅Π½ΠΈΠ΅ΠΌ Π΄Π»Ρ ΡΠΈΠ³Π½Π°Π»ΠΎΠ² Ρ ΠΌΠΈΠ½ΠΈΠΌΠ°Π»ΡΠ½ΡΠΌ ΡΠ΄Π²ΠΈΠ³ΠΎΠΌ ΠΏΡΡΠ΅ΠΌ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ ΡΠ°Π·Π½ΠΎΡΡΠ½ΠΎΠΉ ΡΡΠ½ΠΊΡΠΈΠΈ ΠΎΡΠΈΠ±ΠΊΠΈ Π°ΠΏΠΏΡΠΎΠΊΡΠΈΠΌΠ°ΡΠΈΠΈ (ΠΎΡΠΈΠ±ΠΊΠ° ΠΏΠΎΡΡΠ΄ΠΊΠ° 10-3), ΡΡΠΎ ΠΏΠΎΠ·Π²ΠΎΠ»ΠΈΠ»ΠΎ ΠΏΠΎΠ»ΡΡΠΈΡΡ Π±ΠΎΠ»Π΅Π΅ ΠΊΠΎΠΌΠΏΠ°ΠΊΡΠ½ΠΎΠ΅ ΠΏΡΠ΅Π΄ΡΡΠ°Π²Π»Π΅Π½ΠΈΠ΅ ΡΠ°Π·ΡΠ°Π±ΠΎΡΠ°Π½Π½ΠΎΠΉ ΠΌΠΎΠ΄Π΅Π»ΠΈ ΠΏΡΠΈΠΌΠ΅Π½ΠΈΡΠ΅Π»ΡΠ½ΠΎ ΠΊ ΡΠΈΠ³Π½Π°Π»Π°ΠΌ Ρ Π΄Π²ΠΎΠΉΠ½ΠΎΠΉ ΡΠ°Π·ΠΎΠ²ΠΎΠΉ ΠΌΠΎΠ΄ΡΠ»ΡΡΠΈΠ΅ΠΉ. ΠΠΎΠΊΠ°Π·Π°Π½ΠΎ, ΡΡΠΎ ΡΠ°ΠΊΠΈΠ΅ ΡΠΈΠ³Π½Π°Π»Ρ ΠΎΠ±Π»Π°Π΄Π°ΡΡ Π±ΠΎΠ»Π΅Π΅ Π²ΡΡΠΎΠΊΠΈΠΌΠΈ ΡΠ²ΠΎΠΉΡΡΠ²Π°ΠΌΠΈ ΠΏΠΎΠΌΠ΅Ρ
ΠΎΡΡΡΠΎΠΉΡΠΈΠ²ΠΎΡΡΠΈ ΠΏΠΎ ΠΎΡΠ½ΠΎΡΠ΅Π½ΠΈΡ ΠΊ ΡΠΈΠ³Π½Π°Π»Π°ΠΌ Ρ ΠΌΠΈΠ½ΠΈΠΌΠ°Π»ΡΠ½ΡΠΌ ΡΠ΄Π²ΠΈΠ³ΠΎΠΌ (ΠΏΠΎΡΡΠ΄ΠΊΠ° 0,5 Π΄Π ΠΏΠΎ ΡΡΠΎΠ²Π½Ρ ΠΎΡΠΈΠ±ΠΊΠΈ 10-5). Π£ΠΊΠ°Π·Π°Π½Π½ΡΠΉ ΡΠ΅Π·ΡΠ»ΡΡΠ°Ρ ΠΏΠΎΠ»ΡΡΠ΅Π½ Π½Π° ΠΎΡΠ½ΠΎΠ²Π΅ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ ΡΡΠ½ΠΊΡΠΈΠΉ ΡΠ°Π·Π»ΠΈΡΠΈΡ, ΠΎΠΏΡΠ΅Π΄Π΅Π»ΡΠ΅ΠΌΡΡ
ΡΠ°Π·Π½ΠΎΡΡΡΡ ΠΌΠ΅ΠΆΠ΄Ρ ΡΠΈΠ³Π½Π°Π»ΡΠ½ΡΠΌΠΈ ΡΠΈΠΌΠ²ΠΎΠ»Π°ΠΌΠΈ ΡΠΎΠΎΡΠ²Π΅ΡΡΡΠ²ΡΡΡΠΈΡ
ΠΈΠ½ΡΠΎΡΠΌΠ°ΡΠΈΠΎΠ½Π½ΡΠΌ Π·Π½Π°ΡΠ΅Π½ΠΈΡΠΌ Β«1Β» ΠΈ Β«0Β». ΠΠΏΡΠ΅Π΄Π΅Π»Π΅Π½Ρ Π½Π°ΠΏΡΠ°Π²Π»Π΅Π½ΠΈΡ Π΄Π°Π»ΡΠ½Π΅ΠΉΡΠ΅Π³ΠΎ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ
ΠΠΌΠΏΠΈΡΠΈΡΠ΅ΡΠΊΠΈΠΉ ΠΏΠΎΠ΄Ρ ΠΎΠ΄ ΠΊ ΠΎΡΠ΅Π½ΠΊΠ΅ ΠΏΠΎΠΌΠ΅Ρ ΠΎΡΡΡΠΎΠΉΡΠΈΠ²ΠΎΡΡΠΈ ΡΠΈΠ³Π½Π°Π»ΠΎΠ² ΡΠ°Π·ΠΎΠ²ΠΎΠΉ ΠΌΠΎΠ΄ΡΠ»ΡΡΠΈΠΈ
The high spectral efficiency of signals with continuous phase modulation (CPM) has determined their popularity and active use in various radio engineering projects. The uniqueness of the properties of CPM signals is associated with the preservation of the continuity of their phase when changing information messages for the duration of a symbol. At the same time, until recently, of the entire wide class of signals with continuous phase modulation, the most widespread were various variations, the so-called Minimum Shift Keying (MSK) signals. However, these are far from the only representatives of the class of CPM signals with the property of high spectral compactness. This article examines no less interesting signals of this class, formed by means of Dual Phase Modulation (DPM). In particular, analytical expressions of their synthesis are presented, their belonging to the class of CPM signals is substantiated. In addition, the article investigates the temporal properties of the phase function recommended by ITU-R SM.328-11 for the synthesis of signals with continuous phase modulation, presents the time and frequency fragments of MSK signals in comparison with signals with Binary Phase Shift Keying (BPSK). The stages of the analytical derivation of the model of noise immunity of PCM signals in terms of the probability of a bit error based on an empirical approach are presented. The generality of the obtained model with the known expression for MSK signals is shown by studying the difference function of the approximation error (error of the order of 10-3), which made it possible to obtain a more compact representation of the developed model in relation to DPM signals. It has been proven that DPM signals have higher noise immunity properties in relation to MSK signals (about 0.5 dB at an error level of 10-5), using the results of studying the difference functions determined by the difference between the signal symbols corresponding to the information values "1" and "0". The directions of further research are determined.ΠΡΡΠΎΠΊΠ°Ρ ΡΠΏΠ΅ΠΊΡΡΠ°Π»ΡΠ½Π°Ρ ΡΡΡΠ΅ΠΊΡΠΈΠ²Π½ΠΎΡΡΡ ΡΠΈΠ³Π½Π°Π»ΠΎΠ² Ρ Π½Π΅ΠΏΡΠ΅ΡΡΠ²Π½ΠΎΠΉ ΡΠ°Π·ΠΎΠ²ΠΎΠΉ ΠΌΠΎΠ΄ΡΠ»ΡΡΠΈΠ΅ΠΉ ΠΎΠΏΡΠ΅Π΄Π΅Π»ΠΈΠ»Π° ΠΈΡ
ΠΈΠ·Π²Π΅ΡΡΠ½ΠΎΡΡΡ ΠΈ Π°ΠΊΡΠΈΠ²Π½ΠΎΠ΅ ΠΏΡΠΈΠΌΠ΅Π½Π΅Π½ΠΈΠ΅ Π² ΡΠ°Π·Π»ΠΈΡΠ½ΡΡ
ΡΠ°Π΄ΠΈΠΎΡΠ΅Ρ
Π½ΠΈΡΠ΅ΡΠΊΠΈΡ
ΠΏΡΠΎΠ΅ΠΊΡΠ°Ρ
. Π£Π½ΠΈΠΊΠ°Π»ΡΠ½ΠΎΡΡΡ ΡΠ²ΠΎΠΉΡΡΠ² ΡΠ°ΠΊΠΈΡ
ΡΠΈΠ³Π½Π°Π»ΠΎΠ² ΡΠ²ΡΠ·Π°Π½Π° Ρ ΡΠΎΡ
ΡΠ°Π½Π΅Π½ΠΈΠ΅ΠΌ Π½Π΅ΠΏΡΠ΅ΡΡΠ²Π½ΠΎΡΡΠΈ ΠΈΡ
ΡΠ°Π·Ρ ΠΏΡΠΈ ΡΠΌΠ΅Π½Π΅ ΠΈΠ½ΡΠΎΡΠΌΠ°ΡΠΈΠΎΠ½Π½ΡΡ
ΠΏΠΎΡΡΠ»ΠΎΠΊ Π½Π° Π΄Π»ΠΈΡΠ΅Π»ΡΠ½ΠΎΡΡΠΈ ΡΠΈΠΌΠ²ΠΎΠ»Π°. ΠΠΌΠ΅ΡΡΠ΅ Ρ ΡΠ΅ΠΌ Π΄ΠΎ Π½Π΅Π΄Π°Π²Π½Π΅Π³ΠΎ Π²ΡΠ΅ΠΌΠ΅Π½ΠΈ ΠΈΠ· Π²ΡΠ΅Π³ΠΎ ΡΠΈΡΠΎΠΊΠΎΠ³ΠΎ ΠΊΠ»Π°ΡΡΠ° ΡΠΈΠ³Π½Π°Π»ΠΎΠ² Ρ Π½Π΅ΠΏΡΠ΅ΡΡΠ²Π½ΠΎΠΉ ΡΠ°Π·ΠΎΠ²ΠΎΠΉ ΠΌΠΎΠ΄ΡΠ»ΡΡΠΈΠ΅ΠΉ Π½Π°ΠΈΠ±ΠΎΠ»ΡΡΠ΅Π΅ ΡΠ°ΡΠΏΡΠΎΡΡΡΠ°Π½Π΅Π½ΠΈΠ΅ ΠΏΠΎΠ»ΡΡΠΈΠ»ΠΈ ΡΠ°Π·Π»ΠΈΡΠ½ΡΠ΅ Π²Π°ΡΠΈΠ°ΡΠΈΠΈ ΡΠ°ΠΊ Π½Π°Π·ΡΠ²Π°Π΅ΠΌΡΡ
ΡΠΈΠ³Π½Π°Π»ΠΎΠ² ΡΠ°ΡΡΠΎΡΠ½ΠΎΠΉ ΠΌΠΎΠ΄ΡΠ»ΡΡΠΈΠ΅ΠΉ Ρ ΠΌΠΈΠ½ΠΈΠΌΠ°Π»ΡΠ½ΡΠΌ ΡΠ΄Π²ΠΈΠ³ΠΎΠΌ. ΠΠ΄Π½Π°ΠΊΠΎ ΡΡΠΎ Π΄Π°Π»Π΅ΠΊΠΎ Π½Π΅ Π΅Π΄ΠΈΠ½ΡΡΠ²Π΅Π½Π½ΡΠ΅ ΠΏΡΠ΅Π΄ΡΡΠ°Π²ΠΈΡΠ΅Π»ΠΈ ΠΊΠ»Π°ΡΡΠ° ΡΠΈΠ³Π½Π°Π»ΠΎΠ² Ρ Π½Π΅ΠΏΡΠ΅ΡΡΠ²Π½ΠΎΠΉ ΡΠ°Π·ΠΎΠ²ΠΎΠΉ ΠΌΠΎΠ΄ΡΠ»ΡΡΠΈΠ΅ΠΉ, ΠΎΠ±Π»Π°Π΄Π°ΡΡΠΈΠ΅ ΡΠ²ΠΎΠΉΡΡΠ²ΠΎΠΌ Π²ΡΡΠΎΠΊΠΎΠΉ ΡΠΏΠ΅ΠΊΡΡΠ°Π»ΡΠ½ΠΎΠΉ ΠΊΠΎΠΌΠΏΠ°ΠΊΡΠ½ΠΎΡΡΠΈ.
ΠΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½Ρ Π½Π΅ ΠΌΠ΅Π½Π΅Π΅ ΠΈΠ½ΡΠ΅ΡΠ΅ΡΠ½ΡΠ΅ ΡΠΈΠ³Π½Π°Π»Ρ ΡΡΠΎΠ³ΠΎ ΠΊΠ»Π°ΡΡΠ°, ΡΠΎΡΠΌΠΈΡΡΠ΅ΠΌΡΠ΅ ΠΏΠΎΡΡΠ΅Π΄ΡΡΠ²ΠΎΠΌ Π΄Π²ΠΎΠΉΠ½ΠΎΠΉ ΡΠ°Π·ΠΎΠ²ΠΎΠΉ ΠΌΠΎΠ΄ΡΠ»ΡΡΠΈΠΈ. ΠΡΠ΅Π΄ΡΡΠ°Π²Π»Π΅Π½Ρ Π°Π½Π°Π»ΠΈΡΠΈΡΠ΅ΡΠΊΠΈΠ΅ Π²ΡΡΠ°ΠΆΠ΅Π½ΠΈΡ ΠΈΡ
ΡΠΈΠ½ΡΠ΅Π·Π°, ΠΎΠ±ΠΎΡΠ½ΠΎΠ²Π°Π½Π° ΠΈΡ
ΠΏΡΠΈΠ½Π°Π΄Π»Π΅ΠΆΠ½ΠΎΡΡΡ ΠΊ ΠΊΠ»Π°ΡΡΡ ΡΠΈΠ³Π½Π°Π»ΠΎΠ² Ρ Π½Π΅ΠΏΡΠ΅ΡΡΠ²Π½ΠΎΠΉ ΡΠ°Π·ΠΎΠ²ΠΎΠΉ ΠΌΠΎΠ΄ΡΠ»ΡΡΠΈΠ΅ΠΉ. Π’Π°ΠΊΠΆΠ΅ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½Ρ Π²ΡΠ΅ΠΌΠ΅Π½Π½ΡΠ΅ ΡΠ²ΠΎΠΉΡΡΠ²Π° ΡΠ°Π·ΠΎΠ²ΠΎΠΉ ΡΡΠ½ΠΊΡΠΈΠΈ, ΡΠ΅ΠΊΠΎΠΌΠ΅Π½Π΄ΠΎΠ²Π°Π½Π½ΠΎΠΉ ΠΠ‘Π-R SM.328-11 Π΄Π»Ρ ΡΠΈΠ½ΡΠ΅Π·Π° ΡΠΈΠ³Π½Π°Π»ΠΎΠ² Ρ Π½Π΅ΠΏΡΠ΅ΡΡΠ²Π½ΠΎΠΉ ΡΠ°Π·ΠΎΠ²ΠΎΠΉ ΠΌΠΎΠ΄ΡΠ»ΡΡΠΈΠ΅ΠΉ, ΠΏΡΠΈΠ²Π΅Π΄Π΅Π½Ρ Π²ΡΠ΅ΠΌΠ΅Π½Π½ΡΠ΅ ΠΈ ΡΠ°ΡΡΠΎΡΠ½ΡΠ΅ ΡΡΠ°Π³ΠΌΠ΅Π½ΡΡ ΡΠΈΠ³Π½Π°Π»ΠΎΠ² Ρ ΠΌΠΈΠ½ΠΈΠΌΠ°Π»ΡΠ½ΡΠΌ ΡΠ΄Π²ΠΈΠ³ΠΎΠΌ Π² ΡΡΠ°Π²Π½Π΅Π½ΠΈΠΈ ΡΠΈΠ³Π½Π°Π»Π°ΠΌΠΈ Ρ Π΄Π²ΠΎΠΈΡΠ½ΠΎΠΉ ΡΠ°Π·ΠΎΠ²ΠΎΠΉ ΠΌΠ°Π½ΠΈΠΏΡΠ»ΡΡΠΈΠ΅ΠΉ. ΠΡΠ΅Π΄ΡΡΠ°Π²Π»Π΅Π½Ρ ΡΡΠ°ΠΏΡ Π°Π½Π°Π»ΠΈΡΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ Π²ΡΠ²ΠΎΠ΄Π° ΠΌΠΎΠ΄Π΅Π»ΠΈ ΠΏΠΎΠΌΠ΅Ρ
ΠΎΡΡΡΠΎΠΉΡΠΈΠ²ΠΎΡΡΠΈ ΡΠΈΠ³Π½Π°Π»ΠΎΠ² Ρ Π½Π΅ΠΏΡΠ΅ΡΡΠ²Π½ΠΎΠΉ ΡΠ°Π·ΠΎΠ²ΠΎΠΉ ΠΌΠΎΠ΄ΡΠ»ΡΡΠΈΠ΅ΠΉ ΠΏΠΎ ΠΏΠΎΠΊΠ°Π·Π°ΡΠ΅Π»Ρ Π²Π΅ΡΠΎΡΡΠ½ΠΎΡΡΠΈ Π±ΠΈΡΠΎΠ²ΠΎΠΉ ΠΎΡΠΈΠ±ΠΊΠΈ Π½Π° ΠΎΡΠ½ΠΎΠ²Π΅ ΡΠΌΠΏΠΈΡΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ ΠΏΠΎΠ΄Ρ
ΠΎΠ΄Π°. ΠΠΎΠΊΠ°Π·Π°Π½Π° ΠΎΠ±ΡΠ½ΠΎΡΡΡ ΠΏΠΎΠ»ΡΡΠ΅Π½Π½ΠΎΠΉ ΠΌΠΎΠ΄Π΅Π»ΠΈ Ρ ΠΈΠ·Π²Π΅ΡΡΠ½ΡΠΌ Π²ΡΡΠ°ΠΆΠ΅Π½ΠΈΠ΅ΠΌ Π΄Π»Ρ ΡΠΈΠ³Π½Π°Π»ΠΎΠ² Ρ ΠΌΠΈΠ½ΠΈΠΌΠ°Π»ΡΠ½ΡΠΌ ΡΠ΄Π²ΠΈΠ³ΠΎΠΌ ΠΏΡΡΠ΅ΠΌ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ ΡΠ°Π·Π½ΠΎΡΡΠ½ΠΎΠΉ ΡΡΠ½ΠΊΡΠΈΠΈ ΠΎΡΠΈΠ±ΠΊΠΈ Π°ΠΏΠΏΡΠΎΠΊΡΠΈΠΌΠ°ΡΠΈΠΈ (ΠΎΡΠΈΠ±ΠΊΠ° ΠΏΠΎΡΡΠ΄ΠΊΠ° 10-3), ΡΡΠΎ ΠΏΠΎΠ·Π²ΠΎΠ»ΠΈΠ»ΠΎ ΠΏΠΎΠ»ΡΡΠΈΡΡ Π±ΠΎΠ»Π΅Π΅ ΠΊΠΎΠΌΠΏΠ°ΠΊΡΠ½ΠΎΠ΅ ΠΏΡΠ΅Π΄ΡΡΠ°Π²Π»Π΅Π½ΠΈΠ΅ ΡΠ°Π·ΡΠ°Π±ΠΎΡΠ°Π½Π½ΠΎΠΉ ΠΌΠΎΠ΄Π΅Π»ΠΈ ΠΏΡΠΈΠΌΠ΅Π½ΠΈΡΠ΅Π»ΡΠ½ΠΎ ΠΊ ΡΠΈΠ³Π½Π°Π»Π°ΠΌ Ρ Π΄Π²ΠΎΠΉΠ½ΠΎΠΉ ΡΠ°Π·ΠΎΠ²ΠΎΠΉ ΠΌΠΎΠ΄ΡΠ»ΡΡΠΈΠ΅ΠΉ. ΠΠΎΠΊΠ°Π·Π°Π½ΠΎ, ΡΡΠΎ ΡΠ°ΠΊΠΈΠ΅ ΡΠΈΠ³Π½Π°Π»Ρ ΠΎΠ±Π»Π°Π΄Π°ΡΡ Π±ΠΎΠ»Π΅Π΅ Π²ΡΡΠΎΠΊΠΈΠΌΠΈ ΡΠ²ΠΎΠΉΡΡΠ²Π°ΠΌΠΈ ΠΏΠΎΠΌΠ΅Ρ
ΠΎΡΡΡΠΎΠΉΡΠΈΠ²ΠΎΡΡΠΈ ΠΏΠΎ ΠΎΡΠ½ΠΎΡΠ΅Π½ΠΈΡ ΠΊ ΡΠΈΠ³Π½Π°Π»Π°ΠΌ Ρ ΠΌΠΈΠ½ΠΈΠΌΠ°Π»ΡΠ½ΡΠΌ ΡΠ΄Π²ΠΈΠ³ΠΎΠΌ (ΠΏΠΎΡΡΠ΄ΠΊΠ° 0,5 Π΄Π ΠΏΠΎ ΡΡΠΎΠ²Π½Ρ ΠΎΡΠΈΠ±ΠΊΠΈ 10-5). Π£ΠΊΠ°Π·Π°Π½Π½ΡΠΉ ΡΠ΅Π·ΡΠ»ΡΡΠ°Ρ ΠΏΠΎΠ»ΡΡΠ΅Π½ Π½Π° ΠΎΡΠ½ΠΎΠ²Π΅ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ ΡΡΠ½ΠΊΡΠΈΠΉ ΡΠ°Π·Π»ΠΈΡΠΈΡ, ΠΎΠΏΡΠ΅Π΄Π΅Π»ΡΠ΅ΠΌΡΡ
ΡΠ°Π·Π½ΠΎΡΡΡΡ ΠΌΠ΅ΠΆΠ΄Ρ ΡΠΈΠ³Π½Π°Π»ΡΠ½ΡΠΌΠΈ ΡΠΈΠΌΠ²ΠΎΠ»Π°ΠΌΠΈ ΡΠΎΠΎΡΠ²Π΅ΡΡΡΠ²ΡΡΡΠΈΡ
ΠΈΠ½ΡΠΎΡΠΌΠ°ΡΠΈΠΎΠ½Π½ΡΠΌ Π·Π½Π°ΡΠ΅Π½ΠΈΡΠΌ Β«1Β» ΠΈ Β«0Β». ΠΠΏΡΠ΅Π΄Π΅Π»Π΅Π½Ρ Π½Π°ΠΏΡΠ°Π²Π»Π΅Π½ΠΈΡ Π΄Π°Π»ΡΠ½Π΅ΠΉΡΠ΅Π³ΠΎ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ
Proceedings of the Mobile Satellite Conference
A satellite-based mobile communications system provides voice and data communications to mobile users over a vast geographic area. The technical and service characteristics of mobile satellite systems (MSSs) are presented and form an in-depth view of the current MSS status at the system and subsystem levels. Major emphasis is placed on developments, current and future, in the following critical MSS technology areas: vehicle antennas, networking, modulation and coding, speech compression, channel characterization, space segment technology and MSS experiments. Also, the mobile satellite communications needs of government agencies are addressed, as is the MSS potential to fulfill them
Underwater acoustic communications
The underwater acoustic medium poses unique challenges to the design of robust, high throughput digital communications. The aim of this work is to identify modulation and receiver processing techniques to enable the reliable transfer of data at high rate, at range between two, potentially mobile parties using acoustics. More generally, this work seeks to investigate techniques to effectively communicate between two or more parties over a wide range of channel conditions where data rate is a key but not always the absolute performance requirement. Understanding the intrinsic ocean mechanisms that influence signal coherence, the relationship between signal coherence and optimum signal design, and the development of robust modulation and receiver processing techniques are the main areas of study within this work.
New and established signal design, modulation, synchronisation, equalisation and spatial processing techniques are investigated. Several new, innovative techniques are presented which seek to improve the robustness of βclassicalβ solutions to the underwater acoustic communications problem. The performance of these techniques to mitigate the severe temporal dispersion of the underwater channel and its unique temporal variability are assessed.
A candidate modulation, synchronisation and equalisation architecture is proposed based on a spatial-temporal adaptive signal processing (STAP) receiver. Comprehensive simulation results are presented to demonstrate the performance of the candidate receiver to time selective, frequency selective and spatially selective channel behaviour. Several innovative techniques are presented which maximise system performance over a wider range of operational and environmental conditions.
Field trials results are presented based on system evaluation over a wide range of geographically distinct environments demonstrating system performance over a diverse range of ocean bathymetry, topography and background noise conditions. A real time implementation of the system is reported and field trials results presented demonstrating the capability of the system to support a wide range of data formats including video at useful frame rates.
Within this work, several novel techniques have been developed which have extended the state of the art in high data rate underwater communications:-
β’ Robust, high fidelity open loop synchronisation techniques capable of operating at marginal signal-to-noise ratios over a wide range of severely time spread environments. These high probability of synchronisation, low probability of false alarm techniques, provide the means for βburstβ open loop synchronisation in time, Doppler and space (bearing). The techniques have been demonstrated in communication and position fixing/navigation systems to provide repeatable range accuracyβs to centimetric order.
β’ Novel closed loop synchronisation compensation for STAP receiver architectures. Specifically, this work has demonstrated the performance benefits of including both delay lock loop (DLL) and phase lock loop (PLL) support for acoustic adaptive receivers to offload tracking effort from the fractional feedforward equaliser section. It has been shown that the addition of a DLL/PLL outperforms the PLL only case for Doppler errors exceeding a few fractions of a knot.
β’ Recycling of training data has been demonstrated as a potentially useful means to improve equaliser convergence in difficult acoustic channels. With suitable processing power, training data recycling introduces no additional transmission time overhead, which may be a limiting factor in battery powered applications.
β’ Forward and time reverse decoding of packet data has been demonstrated as an effective means to overcome some non-minimum phase channel conditions. It has also been shown that there may be further benefits in terms of improved bit error performance, by exploiting concurrent forward and backward symbol data under modest channel conditions.
β’ Several wideband techniques have been developed and demonstrated to be effective at resolving and coherently tracking difficult doubly spread acoustic channels. In particular, wideband spread spectrum techniques have been shown to be effective at resolving acoustic multipath, and with the aid of independent delay lock loops, track individual path arrivals. Techniques have been developed which can effect coherent or non-coherent recombination of these paths with a view to improving the robustness of an acoustic link operating at very low signal-to-noise levels.
β’ Demonstrated throughputs of up to 41kbps in a difficult, tropical environment, featuring significant biological noise levels for mobile platforms at range up to 1.5km.
β’ Demonstrated throughputs of between 300bps and 1600bps in a shallow, reverberant environment, at a range up to 21km at LF.
β’ Implemented and demonstrated all algorithms in real time systems
Band sharing and satellite diversity techniques for CDMA.
High levels of interference between satellite constellation systems, fading and shadowing are a major problem for the successful performance of communication systems using the allocated L/S frequency bands for Non-Geostationary Earth Orbit (NGEO) satellites. As free spectrum is nonexistent, new systems wishing to operate in this band must co-exist with other users, both satellite and terrestrial. This research is mainly concerned with two subjects. Firstly, band sharing between different systems Code Division Multiple Access (CDMA) and Time Division Multiple Access (TDMA) has been evaluated for maximizing capacity and optimising efficiency of using the spectrum available. For the case of widened channel bandwidth of the CDMA channel, the overlapping was tested under different degrees of channel overlap and different orders of filters. The best result shows that at the optimum degree of channel overlap, capacity increases by up to 21%. For the case of fixed channel bandwidth, the optimum overlapping between CDMA systems depends on the filtering Roll-off factor and achieves an improvement of the spectrum efficiency of up to 13.4%. Also, for a number of narrowband signal users sharing a CDMA channel, the best location of narrowband signals to share spectrum with a CDMA system was found to be at the edge of the CDMA channel. Simulation models have been constructed and developed which show the combination of DS- CDMA techniques, forward error correction (FEC) code techniques and satellite diversity with Rake receiver for improving performance of interference, fading and shadowing under different environments. Voice activity factor has been considered to reduce the effect of multiple access interference (MAI). The results have shown that satellite diversity has a significant effect on the system performance and satellite diversity gain achieves an improvement up to 6dB. Further improvements have been achieved by including concatenated codes to provide different BER for different services. Sharing the frequency band between a number of Low Earth Orbit (LEO) satellite constellation systems is feasible and very useful but only for a limited number of LEOS satellite CDMA based constellations. Furthermore, satellite diversity is an essential factor to achieve a satisfactory level of service availability, especially for urban and suburban environments
Synchronisation in sampled receivers for narrowband digital modulation schemes.
SIGLEAvailable from British Library Document Supply Centre- DSC:DXN0033576 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
Storia delle telecomunicazioni
Focusing on the history of scientific and technological development over recent centuries, the book is dedicated to the history of telecommunications, where Italy has always been in the vanguard, and is presented by many of the protagonists of the last half century. The book is divided into five sections. The first, dealing with the origins, starts from the scientific bases of the evolution of telecommunications in the nineteenth century (Bucci), addressing the developments of scientific thought that led to the revolution of the theory of fields (Morando), analysing the birth of the three fundamental forms of communication β telegraph (Maggi), telephone (Del Re) and radio (Falciasecca) β and ending with the contribution made by the Italian Navy to the development of telecommunications (Carulli, Pelosi, Selleri, Tiberio). The second section, on technical and scientific developments, presents the numerical processing of signals (Rocca), illustrating the genesis and metamorphosis of transmission (Pupolin, Benedetto, Mengali, Someda, Vannucchi), network packets (Marsan, Guadagni, Lenzini), photonics in telecommunications (Prati) and addresses the issue of research within the institutions (Fedi-Morello), dwelling in particular on the CSELT (Mossotto). The next section deals with the sectors of application, offering an overview of radio, television and the birth of digital cinema (Vannucchi, Visintin), military communications (Maestrini, Costamagna), the development of radar (Galati) and spatial telecommunications (Tartara, Marconicchio). Section four, on the organisation of the services and the role of industry, outlines the rise and fall of the telecommunications industries in Italy (Randi), dealing with the telecommunications infrastructures (Caroppo, Gamerro), the role of the providers in national communications (Gerarduzzi), the networks and the mobile and wireless services (Falciasecca, Ongaro) and finally taking a look towards the future from the perspective of the last fifty years (Vannucchi). The last section, dealing with training and dissemination, offers an array of food for thought: university training in telecommunications, with focus on the evolution of legislation and on the professional profiles (Roveri), social and cultural aspects (Longo and Crespellani) as well as a glance over the most important museums, collections and documentary sources for telecommunications in Italy (Lucci, Savini, Temporelli, Valotti). The book is designed to offer a compendium comprising different analytical approaches, and aims to foster an interest in technology in the new generations, in the hope of stimulating potentially innovative research