Method for reception of long range signals in bluetooth

Abstract

The invention of a method for reception of long transmission range Bluetooth signals impaired by multipath are disclosed. The new reception method proposed allows to increase the transmission range for data transmission in Bluetooth. The invention proposes the use of a new FDE adapted to SC transmission without a GI or CP. The proposed FDE very successfully mitigates ISI while being very implemention-friendly.

1 . A method for reception of long-range signals in Bluetooth for all transmission modes on power class 1, power class 2 and power class 3, the method comprising:
 receiving Bluetooth signals; and   processing said Bluetooth signals with linear frequency-domain equalization (FDE) in single carrier (SC) system using a Fourier Transform.   
     
     
         2 . The method for reception of long-range signals in Bluetooth according to  claim 1 , wherein said Fourier Transform is a Discrete Fourier Transform (DFT) deduced from a Fast Fourier Transform (FFT). 
     
     
         3 . The method for reception of long-range signals in Bluetooth according to  claim 2 , wherein said Fast Fourier Transform (FFT) is overlap-add-technique FFT or overlap-save-technique FFT. 
     
     
         4 . The method for reception of long-range signals in Bluetooth according to  claim 1 , wherein said Fourier Transform is an Inverse Discrete Fourier Transform deduced from an Inverse Fast Fourier Transform (IFFT). 
     
     
         5 . The method for reception of long-range signals in Bluetooth according to  claim 4 , wherein said Inverse Fast Fourier Transform (IFFT) is overlap-add-technique IFFT or overlap-save-technique IFFT. 
     
     
         6 . The method for reception of long-range signals in Bluetooth according to  claim 1 , further comprising executing an estimate of the transmit data after receiving said Bluetooth signals. 
     
     
         7 . The method for reception of long-range signals in Bluetooth according to  claim 6 , wherein said estimate of the transmit data is obtained using Matched Filter (MF) criterion. 
     
     
         8 . The method for reception of long-range signals in Bluetooth according to  claim 6 , wherein said estimate of the transmit data is obtained using Zero Forcing (ZF) criterion. 
     
     
         9 . The method for reception of long-range signals in Bluetooth according to  claim 6 , wherein said estimate of the transmit data is obtained using Minimum Mean Square Error (MMSE) criterion. 
     
     
         10 . The method for reception of long-range signals in Bluetooth according to  claim 9 , wherein said minimum mean square error (MMSE) is obtained from
     {circumflex over (d)}   MMSE   =F   −1   {H   inv   ·F ( r )}   
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         11 . The method for reception of long-range signals in Bluetooth according to  claim 10 , wherein said F and F −1  size is 8 or 16. 
     
     
         12 . The method for reception of long-range signals in Bluetooth according to  claim 9 , wherein said minimum mean square error (MMSE) comprises:
 using FFT on estimated channel impulse response ĥ yielding Ĥ;   conjugating complex operation on Ĥ;   multiplying of Ĥ with conj(Ĥ);   adding of Ĥ·H* with σ 2 ;   dividing of Ĥ* by Ĥ·H*+σ 2 ;   multiplying with phasors   
       
         
           
             
               
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         13 . The method for reception of long-range signals in Bluetooth according to  claim 1 , wherein said transmission modes comprises 1 Mbps transmission mode (GFSK), 2 Mbps transmission mode (DPSK), and 3 Mbps transmission mode (DPSK).