HR: 0800h
AN: G21A-0094    [Abstracts]
TI: The multipath and SNR Quality in civil code L2
AU: * Polezel, W G
EM: wesleypolezel@hotmail.com
AF: UNESP, Rua Roberto Simonsen,305, Presidente Prudente, SP 19060-900,
AU: Souza, E M
EM: eniuce@yahoo.com.br
AF: UNESP, Rua Roberto Simonsen,305, Presidente Prudente, SP 19060-900,
AU: Monico, J F
EM: galera@fct.unesp.br
AF: UNESP, Rua Roberto Simonsen,305, Presidente Prudente, SP 19060-900,
AB: The new generation of GPS satellites, with the addition of the new L2C civil code, may provide to the users better positioning capabilities. The new code in the L2 may increase the signal robustness, improve resistance to interference, reduce tracking noise and consequently, improve accuracy and provide better positioning inside buildings and in wooded areas. The second civil frequency code will eliminate the need of using fragile semi- codeless tracking techniques currently used in connection with L2. The L2C has a different structure that allows civil and military share the same code. L2C owns two codes of different length: moderate code (CM) and long code (CL). The CM was chosen to have 10.230 chips repeated to every 20 millisecond. The CL was chosen to have 767250 chips with period of 1.5 second. The main reasons for these choices were due to excellent correlation properties. Furthermore, L2C enhances performance by having no data modulation on CL code, which improves, among others, the threshold tracking performance. Comparing the L2C acquisition with the C/A, the CM code is ten times longer than the C/A and the two components have half the total power. This is an important feature for many low-power applications. Although this signal has several advantages, some investigations about its performance are necessary, mainly about the provided accuracy under some effects, for example, multipath. Thus, this paper aims to analyze the L2C signal, as well as its quality using some parameters, such as Signal to Noise Ratio (SNR) and multipath level (MP). The experiment was realized at Sao Paulo State University UNESP in Presidente Prudente, Brazil. The data were collected by two receivers of different brands, both able to collect the L2C signal, and connected to the same antenna, thought the use of a splitter. The results showed that the MP and SNR values were better for the modernized satellites. Furthermore, the SNR values of the two receivers were similar while the MP values of one receiver showed better results than the other model. Therefore, the satellites with L2C code presented, as expected, better performance than those not modernized satellites in relation to SNR and MP.
DE: 1240 Satellite geodesy: results (6929, 7215, 7230, 7240)
DE: 6929 Ionospheric physics (1240, 2400)
DE: 7215 Earthquake source observations (1240)
DE: 7230 Seismicity and tectonics (1207, 1217, 1240, 1242)
DE: 7240 Subduction zones (1207, 1219, 1240)
SC: Geodesy [G]
MN: 2007 Fall Meeting