Power-based hardware diversity

Abstract

A power-based hardware antenna diversity method for a wireless transceiver with multiple antennas is disclosed. The method is characterized in the steps of setting the transceiver gain at a maximum level to establish a first story of dynamic power range above a noise floor level, using a high-resolution ADC at a large back-off level relative to the noise floor to detect weak signals within the first story of the dynamic power range, switching antennas and measuring power level for each antenna during signal onset, and selecting an antenna having a largest power level.

1. A power-based hardware antenna diversity method for a wireless transceiver with multiple antennas, comprising:
 setting gain at a maximum level to establish a first story of dynamic power range above a noise floor level; 
 using a high-resolution ADC at a large back-off level relative to the noise floor to detectdetecting weak signals within the first story of the dynamic power range; 
 switching antennas and measuring power level for each antenna during signal onset; and 
 selecting an antenna having a largest power level. 
 
     
     
       2. The power-based hardware antenna diversity method of  claim 1 , further comprising:
 measuring a DC characteristic for each antenna; 
 storing each measured DC characteristic; and 
 applying a corresponding DC characteristic during said step of switching antennas and measuring power level for each antenna. 
 
     
     
       3. The power-based hardware antenna diversity method of  claim 2 , wherein said measuring comprises measuring at EOP. 
     
     
       4. The power-based hardware antenna diversity method of  claim 1 , further comprising measuring gain characteristics of each antenna and storing corresponding gain mitigation values. 
     
     
       5. The power-based hardware antenna diversity method of  claim 1 , further comprising measuring relative noise floor gain differences between each antenna and storing corresponding gain mitigation values. 
     
     
       6. The power-based hardware antenna diversity method of  claim 1 , further comprising employing at least two long sync correlators for performing course frequency offset estimation at the beginning of a long sync section of an incoming packet. 
     
     
       7. A method for performing hardware diversity based on power in a wireless transceiver having multiple antennas, comprising:
 setting a transceiver gain at a maximum level to establish a first story of dynamic power range above a noise floor level; 
 using a high-resolution ADC at a large back-off level relative to the noise floor to detectdetecting weak signals within the first story of the dynamic power range; 
 switching antennas and measuring power level for each antenna during signal onset; and 
 selecting an antenna having a largest measured power level. 
 
     
     
       8. The method of  claim 7 , further comprising:
 measuring a DC characteristic for each antenna; 
 storing each measured DC characteristic in a memory; and 
 for each antenna, applying a corresponding DC characteristic during said step of measuring the power level. 
 
     
     
       9. The method of claim  7  8, wherein said measuring comprises measuring at EOP. 
     
     
       10. The method of  claim 7 , further comprising measuring gain characteristics of each antenna and storing corresponding gain mitigation values in a memory. 
     
     
       11. The method of  claim 7 , further comprising measuring relative noise floor gain differences between each antenna and storing corresponding gain mitigation values in a memory. 
     
     
       12. The method of  claim 7 , further comprising employing at least two long sync correlators for performing course frequency offset estimation at the beginning of a long sync section of an incoming packet. 
     
     
       13. The power-based hardware antenna diversity method of claim 1, further comprising:
 setting gain at a second maximum level different from the first maximum gain level to establish a second story of dynamic power range above the first story; and   using one or more second high-resolution ADCs to detect signals within the second story of the dynamic power range.    
     
     
       14. A wireless communications device for communicating over a wireless medium, the device comprising:
 a plurality of antennas,   a baseband processor configured to generate a hardware diversity control signal to select one or more of the plurality of antennas;   a receiver selectively coupled to the plurality of antennas based at least in part on the hardware diversity control signal and having a dynamic range between a largest expected input signal power level and a minimum noise floor power level;   one or more amplifiers coupled to the receiver and configured at a first maximum gain level to establish a first story of dynamic power range above a noise floor level as a sub-range of the dynamic range; and   one or more analog to digital converters (ADCs) coupled to the one or more amplifiers and configured to detect signals within the first story of dynamic power range;   wherein the baseband processor is further configured to, upon onset of a data packet signal, determine whether the data packet signal causes an over power signal condition in the one or more amplifiers indicating a signal power level above the first story, determine whether the data packet signal causes a clipping signal condition in the one or more ADCs indicating a signal power level above the first story, and if no over power signal condition or clipping signal condition is present, determine that the power level of the data packet signal is within the first story of the dynamic power range and switch to another of the plurality of antennas to measure a power level during packet onset.    
     
     
       15. The device of claim 14, wherein the baseband processor is further configured to:
 measure a DC characteristic for each antenna;   store each measured DC characteristic in a memory; and   apply a corresponding DC characteristic when measuring the power level for the corresponding antenna.    
     
     
       16. The device of claim 15, wherein the baseband processor is configured o measure the DC characteristic for each antenna at end of packet (EOP).  
     
     
       17. The device of claim 14, wherein the baseband processor is configured to measure gain characteristics of each antenna and store corresponding gain mitigation values in a memory.  
     
     
       18. The device of claim 14, wherein the baseband processor is configured to measure relative noise floor gain differences between each antenna and store corresponding gain mitigation values in a memory.  
     
     
       19. The device of claim 14, further comprising at least two long sync correlators for performing course frequency offset estimation at the beginning of a long sync section of the onset data packet.  
     
     
       20. The device of claim 14, further comprising:
 one or more second amplifiers cooled to the receiver and configured at a second maximum gain level different from the first maximum gain level to establish a second story of dynamic power range above the first story, and   one or more second analog to digital converters (ADCs) coupled to the one or more second amplifiers and configured to detect signals within the second story of dynamic power range.    
     
     
       21. A method, comprising:
 detecting receipt of a data packet signal via at least one of a plurality of antennas;   setting gain of one or more amplifiers coupled to the at least one of the plurality of antennas at a first maximum level to establish a first story of dynamic power range above a noise floor level as a sub-range of a larger dynamic range supported by the wireless transceiver,   determining whether a signal power level is above the first story by detecting if the data packet signal causes an over power signal in the one or more amplifiers;   detecting signals within the first story of the dynamic power range;   determining whether the signal power level is above the first story by detecting a clipping signal condition; and   measuring the signal power level upon data packet receipt using another antenna of the plurality of antennas if the power level of the data packet signal is within the first story power range, and if no over power signal condition or clipping signal condition is met.    
     
     
       22. The method of claim 21, further comprising:
 measuring a DC characteristic for each antenna;   storing each measured DC characteristic in a memory; and   applying a corresponding DC characteristic when measuring the power level for the corresponding antenna.    
     
     
       23. The method of claim 22, wherein the step of measuring the DC characteristic for each antenna occurs at end of packet (EOP).  
     
     
       24. The method of claim 21, further comprising measuring gain characteristics of each antenna and storing corresponding gain mitigation values in a memory.  
     
     
       25. The method of claim 21, further comprising measuring relative noise floor gain differences between each antenna and storing corresponding gain mitigation values in a memory.  
     
     
       26. The method of claim 21, further comprising employing at least two long sync correlators for performing course frequency offset estimation at the beginning of a long sync section of the onset data packet.  
     
     
       27. The method of claim 21, further comprising:
 setting gain of one or more second amplifiers coupled to the at least one of said antennas at a second maximum level different from the first maximum gain level to establish a second story of dynamic power range above the first story; and   using one or more second high-resolution ADCs to detect signals within the second story of the dynamic power range.