Download LAMBDA source code
The key of precise GNSS applications is to resolve the double-differenced (DD) carrier phase
ambiguities. One of the methods to do this is the LAMBDA method which was introduced by Teunissen (1993) and developed
at the Delft University of Technology in the 1990s. LAMBDA stands for
Least-squares AMBiguity Decorrelation Adjustment.
With the LAMBDA method, the integer least squares (ILS) ambiguity estimates are computed in two steps.
First the ambiguities are decorrelated, by means of the Z-transformation. The decorrelation is essential to allow for
an efficient search for the integer candidate which solves the integer minimization problem. This search is the second
step in the LAMBDA method.
Fill the form below and press Submit to obtain the compress file with the selected version
of LAMBDA. It may be necessary to use
7zip to decompress the file.
For questions or problems concerning LAMBDA please contact Sandra Verhagen at
Bofeng Li at
Amir Allahvirdizadeh at
Terms and conditions
- LAMBDA: the LAMBDA software produced by the GNSS research centres at
Curtin University and
Delft University of Technology. This extended version of LAMBDA was developed by researchers from Curtin University under the CRCSI Project 1.01 `New carrier-phase processing strategies for next generation GNSS'.
- LAMBDA Team (or “We”): The providers and management of LAMBDA
- User: person, institution or program using LAMBDA
- Registrant: person who has registered their usage of LAMBDA
- Anyone may register their usage of LAMBDA.
- All details provided at registration time will be kept private and used for analytical purposes only.
We may contact you using these details if you have opted in for e-mail pertaining to relevant news and updates.
- Any personal information provided will be handled in accordance with the Western Australia’s Data Protection
legislation. No personal data shall be made public without prior consent from the User.
Content and Services
- LAMBDA is available free of charge to be used by any individual and for any purpose except where specific
restrictions are indicated.
- We do not guarantee the accuracy of any data, software or services appearing in or connected via LAMBDA for any
purpose and accept no responsibility for consequences of their use.
- We decline any responsibility concerning the content and use of other services and web services reached from or
connected to LAMBDA.
- We regard the nature of the work carried out by any individual User as confidential; We have no access to what
users do with LAMBDA.
- We will make all reasonable effort to maintain continuity of LAMBDA and provide adequate warning of any changes or
discontinuities. However, we accept no responsibility for the consequences of any temporary or permanent
discontinuity to LAMBDA.
- We place no restrictions on the use of LAMBDA. However, we do not allow the redistribution of LAMBDA, that must be
obtained exclusively from this website.
Cite the LAMBDA software in your publications as:
"Verhagen, S., Li, B., and Teunissen, P.J.G. (2012). LAMBDA - Matlab implementation, version 3.0. Delft University of Technology and Curtin University".