Receiver for wireless telecommunication stations and method
The present invention is directed to an improved telecommunication receiver for receiving wireless multi-path communication signals. A novel RAKE receiver and a time diverse integration system for the calculation of the relative power of received signal samples are provided. Preferably, the receiver is embodied in a UE or base station of a CDMA wireless telecommunication system, such as a 3GPP system.
1. A receiver for receiving wireless communications including a RAKE receiver configurable with a plurality of RAKE fingers for estimating and combining a plurality of different signal paths of a received communication, comprising:
a RAKE finger locator configured to define windows of a predetermined number of consecutive signal samples within a set of samples that each have a first channel power and a second channel power and to calculate an average first channel power of windows;
said RAKE finger locator further configured to determine whether the average first channel power of a window meets a first threshold such that:
if the average first channel power of the window meets the first threshold, the number of samples in that window whose second channel power exceeds a second threshold is identified as a count; and
if the count exceeds a preselected number, then that window is allocated to a FAT finger of the RAKE receiver.
2. The receiver of claim 1 wherein said RAKE receiver further comprises a RAKE relocator configured to reassign signal paths when the timing of the signal paths change.
3. The receiver of claim 1 wherein said RAKE receiver is configurable with up to five RAKE fingers of which up to one RAKE finger is a FAT finger.
4. A User Equipment (UE) for a CDMA wireless communication system comprising the receiver of claim 1 .
5. A Base Station for a CDMA wireless communication system comprising the receiver of claim 1 .
6. A CDMA wireless communication system comprising User Equipments (UEs) and a Base Station that each comprise the receiver of claim 1 .
7. The receiver of claim 1 wherein said RAKE finger locator is configured to allocate a window to the FAT finger of the RAKE receiver in connection with comparing that window's count to a lowest value such that:
if the count meets the lowest value, then the count is compared to a required value;
if the count meets the required value, then the window is allocated to the Fat finger;
if the count does not meet the required value, then
close signals in the window are pruned;
the number of pruned signals in the window that meet the second threshold are determined as a pruned count; and
if the pruned count meets a predetermined acceptable level, then the window is allocated to the Fat finger.
8. A User Equipment (UE) for a CDMA wireless communication system comprising the receiver of claim 7 .
9. A Base Station for a CDMA wireless communication system comprising the receiver of claim 7 .
10. A CDMA wireless communication system comprising User Equipments (UEs) and a Base Station that each comprise the receiver of claim 7 .
11. A receiver for receiving wireless communications including a RAKE receiver configurable with a plurality of RAKE fingers for estimating and combining a plurality of different signal paths of a received communication, comprising:
a RAKE finger locator configured to process communication signals based on a set of consecutive signal samples where each sample has a first channel power and a second channel power;
said RAKE finger locator configured to rank samples in descending order according to the first channel power of the samples, to select M largest first channel power samples that are at least two samples apart, and to compare the first channel power of each of the M samples with a predetermined threshold to define a set of L samples, where M is greater than or equal to L and where each of the L samples has a first channel power level greater than the predetermined threshold; and
said RAKE finger locator further configured to select K largest second power level samples from the L samples, where L is greater than or equal to K, where K is less than or equal to the number of RAKE fingers to be allocated, and where the second channel power level of each of the K samples exceeds a second power level threshold.
12. A User Equipment (UE) for a CDMA wireless communication system comprising the receiver of claim 11 .
13. A Base Station for a CDMA wireless communication system comprising the receiver of claim 11 .
14. A CDMA wireless communication system comprising User Equipments (UEs) and a Base Station that each comprise the receiver of claim 11 .