Uzun bazlı GPS ağlarında faz bilinmeyeni (Ambiguity) çözüm yöntemleri

Günümüzde GPS'nin, ortaya konulan sonuçlar bakımından yüksek duyarlıklı jeodezik ağların oluşturulmasında vazgeçilmez bir ölçüm tekniği olduğu kanıtlamıştır. Elbet her ölçüm tekniğinde olduğu gibi GPS'de de bazı sorunlar bulunmaktadır. Bunların en önemlilerinden birisi iyonosferik refraksiy ondur, îyonosferin GPS gözlemlerindeki bozucu etkisi, çoğunlukla faz bilinmeyenlerinin doğru çözümünü zorlaştırmaktadır. Bu etki hatasal bir büyüklük olarak özellikle uzun bazlarda oldukça artmaktadır. Bu makalede uzun bazlarda doğruluğu etkileyen en önemli unsur olan tam sayı faz bilinmeyenlerinin çözümü için farklı firmalar tarafından üretilmiş olan yazılımlarda uygulanan değişik yöntemler genel olarak açıklanmış ve irdelenmiştir.

Ambiguity resolution techniques for GPS networks with long baselines

Nowadays, it is well known that GPS is a top technique among the measurement methods used for high precision geodetic networks. As each measurement technique has its own problems that the technique must overcome, GPS also has some. The most important one is ionospheric refraction. The effect of ionospheric refraction on GPS observations mostly appears as a constraining factor for the solution of GPS ambiguities. Especially, this effect reaches to large extents in long baselines.In this paper, first, the methods used for the solution of initial ambiguities, which are the most important factor effecting the accuracy of long baselines, are reviewed. Then the most appropriate ambiguity resolution methods are emphasized for some geodetic networks.

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