Frequency offset estimation between a mobile communication terminal and a network node

摘要

There is disclosed a method for estimating a frequency offset between a mobile communication terminal and a network node. The method is based on processing, by means of a matched filter, a preamble sequence for random access received on a physical random access channel, PRACH. Thus the method is preferably applied in the Evolved Universal Terrestrial Radio Access (E-UTRA) network. In the matched filtered preamble sequence two peaks are determined and the frequency offset is based on a ratio of the two peaks. A corresponding network node, computer program and computer program product are also presented. The network node is preferably performed in a network node of the type eNodeB, E-UTRAN NodeB, also known as Evolved NodeB.

主权项

1. A method for estimating a frequency offset between a mobile communication terminal and a network node, the method being performed in said network node, comprising the steps of:
receiving a preamble sequence for random access on a physical random access channel, PRACH, originating from said mobile communication terminal; processing said preamble sequence for random access, thereby generating an output sequence comprising at least one delay line; determining a first peak in said output sequence and a second peak in said output sequence, wherein said first peak and said second peak correspond to the same at least one delay line in the output sequence; determining a frequency offset estimate based on a ratio of an amplitude of said first peak and an amplitude of said second peak; and applying frequency compensation, using the determined frequency offset estimate, to an uplink communication received from the mobile communication terminal.