Çağatay Aydın, Doğu Çağdaş Atilla, Şakir Yılmaz

TETRA baz istasyonları arasında frekans planlaması

Günümüzde kısıtlı frekans kaynaklarının tekrarlanarak kullanılması frekans planlama açısından ciddi önem arz etmektedir. Özellikle kritik ses haberleşmesinde daha az baz istasyonu ile daha fazla alan kapsanmak istendiğinde frekans tekrarı sorunu daha çok göze batmaktadır. Bu makalede kritik ses haberleşmesi teknolojilerinden olan Karasal Trunk Telsiz sistemi (Terrestrial Trunk Radio, TETRA) üzerinde bir çalışma yapılmıştır. Baz istasyonları konumları, yayın yaptığı frekans bilgisi, baz istasyonu çıkış gücü, sisteme ait bant genişliği göz önüne alınarak komşu kanal ve ortak kanal girişimleri incelenmiştir. Sayısal telsiz sisteminde mevcut hesapların yetersiz kaldığı ve bu hesaplara ek olarak komşuluk ilişkilerinin de frekans planlamada önemli olduğu tespit edilmiştir. Ayrıca konuşma trafiği yoğunluğu (Erlang) incelenerek sistemde işlevsiz kullanılan frekanslar tespit edilmeye çalışılmıştır.

Anahtar Kelimeler:

TETRA, Frekans planlama, frekans tekrarı frekans atama, interferans

Frequency plannig between TETRA base stations

Frequency reuse is necessary for wireless communications due to limited frequency. Especially, mission critical communication users usually want to communicate in a wide area with minimum number of base stations. This request increases the frequency demand and this problem could be solved by RF optimization and frequency planning in order to reuse frequencies. This paper suggests a frequency plan to a TETRA system by analyzing traffic load, interference and using neighborhood between base stations.

Keywords:

TETRA, Frequency planning, Frequency reuse, adjacent and co channel interference,

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A. M. C. A. Koster, Frequency Assignment: Models and Algorithms. PhD Thesis, Maastricht University, Maastricht, Netherlands, 1999.
H. Thuve. Frequency planning as a set partitioning problem. European Journal of Operational Research, 6(1), 29-37, 1981. https://doi.org/10.1016/0377-2217 (81)90325-8.
A. Eisenblatter, M. Grötschel and A. M. C. A. Koster, Frequency Planning and Ramifications of Coloring. Discussiones Mathematicae Graph Theory, 22(1), 51-88, 2002. https://doi.org/10.7151/dmgt.1158.
R.C. Santiago, A .Raymond and V. Lyanders, Enhanced Efficiency and Frequency Assignment by Optimizing the Base Station Location in a Mobile Radio Network. Springer, 14(4), 531-541, 2008. https:/ /doi .org/10.1007 /s11276-006-0735-5.
A. Annunziato and D. Sorbara, TETRA radio performance evaluated via the software package. Mobile Networks and Applications, 5(1), 17-26, 2000. https://doi.org/10.1023/A:1019123620969.
EN 300 392-2 V3.8.1, Terrestrial Trunked Radio (TETRA) - Voice plus Data (V+D) Part 2: Air Interface (AI). European Telecommunications Standards Institute, Sophia Antipolis, 2016.
EN 300 392-2 V2.3.2, Terrestrial Trunked Radio (TETRA) - Voice plus Data (V+D) Part 2: Air Interface (AI). European Telecommunications Standards Institute, Sophia Antipolis, 2001.
W. Webb, The Complete Wireless Communications Professional: A Guide for Engineers and Managers. in: W. Webb (Eds.), The Basics of Mobile Radio, Artech House, pp. 34-37, Norwood, 1999.
P. Stavroulakis, Terrestrial Trunked Radio - TETRA A Global Security Tool. in: P. Stavroulakis (Eds.), TETRA Providing an Acceptable Security, Springer, pp. 52-55, Berlin, 2007.
I. Stojmenovic, Handbook of Wireless Networks and Mobile Computing. in: I. Stojmenovic (Eds.), Interference in Cellular System, Wiley Interscience Publication, pp. 52-53, Newyork, 2002.
J. Walrand and P. Varaiya, High-performance Communication Networks. in: J. Walrand and P. Varaiya (Eds.), The Wireless Channel, Morgan Kaufmann, pp. 305-361, California, 2000
Y. Li, X. Sha, L. Ye and X. Fang, Downlink Resource Sharing for D2D Communications in a Filtered OFDM System. 2016 IEEE 83rd Vehicular Technology Conference (VTC Spring), pp. 1-6, Nanjing, China, 15-18 May 2016.
J. Dunlop, D. Girma and J. Invine, Digital Mobile Communications and TETRA System. in: J. Dunlop, D. Girma and J. Invine (Eds.), Interference to Other System, John Wiley&Sons, pp. 249, West Sussex, 1999.
H. Hammuda, Cellular Mobile Radio System. in: H. Hammuda (Eds.), Co-Channel Interference Model, John Wiley&Sons, pp. 47-66, West Sussex, 1997.
Spectrum Efficiency of CDMA-PAMR and Other Wideband Systems for PMR/PAMR. Electronic Communications Committee, Granada, Spain, ECC Report 042, February 2004.
S. Winder and J. Carr, Newnes Radio and RF Engineering Pocket Book. in: S. Winder (Eds.), Propagation of radio waves, Newnes, pp. 1-24, Woburn, 2002.