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This work aims to estimate soil moisture and vegetation height from Global\udNavigation Satellite System (GNSS) Signal to Noise Ratio (SNR) data using\uddirect and reflected signals by the land surface surrounding a ground-based\udantenna. Observations are collected from a rainfed wheat field in\udsouthwestern France. Surface soil moisture is retrieved based on SNR phases\udestimated by the Least Square Estimation method, assuming the relative\udantenna height is constant. It is found that vegetation growth breaks up the\udconstant relative antenna height assumption. A vegetation-height retrieval\udalgorithm is proposed using the SNR-dominant period (the peak period in the\udaverage power spectrum derived from a wavelet analysis of SNR). Soil moisture\udand vegetation height are retrieved at different time periods (before and\udafter vegetation's significant growth in March). The retrievals\udare compared with two independent reference data sets: in situ\udobservations of soil moisture and vegetation height, and numerical\udsimulations of soil moisture, vegetation height and above-ground dry biomass\udfrom the ISBA (interactions between soil, biosphere and atmosphere) land\udsurface model. Results show that changes in soil moisture mainly affect the\udmultipath phase of the SNR data (assuming the relative antenna height is\udconstant) with little change in the dominant period of the SNR data, whereas\udchanges in vegetation height are more likely to modulate the SNR-dominant\udperiod. Surface volumetric soil moisture can be estimated (R2  =  0.74, RMSE  =  0.009 m3 m−3) when the wheat is smaller than one wavelength (∼ 19 cm). The quality of the estimates markedly decreases when the vegetation height increases. This is because the reflected GNSS signal is less affected by the soil. When vegetation replaces soil as the dominant\udreflecting surface, a wavelet analysis provides an accurate estimation of the\udwheat crop height (R2  =  0.98, RMSE  =  6.2 cm). The latter correlates with modeled above-ground dry biomass of the wheat from stem elongation to ripening. It is found that the vegetation height retrievals are sensitive to changes in plant height of at least one wavelength. A simple smoothing of the retrieved plant height allows an excellent matching to in situ\udobservations, and to modeled above-ground dry biomass

Use of reflected GNSS SNR data to retrieve either soil moisture or vegetation height from a wheat crop