Multi-mode wireless communication link

Abstract

A communication system includes first and second transmitters, which are coupled to transmit respective first and second Radio Frequency (RF) signals carrying first and second data over a wireless communication channel. The transmitters are coupled to select an operational mode from a group of operational modes and to operate in the selected operational mode. The group of the operational modes includes at least two of a protection mode, wherein the second transmitter serves as backup to the first transmitter, a spatial multiplexing mode, in which the first data is different from the second data and the first and second transmitters transmit simultaneously, and a beam-forming mode, in which the first data is identical to the second data, the second RF signal includes a phase-shifted replica of the first RF signal, and the first and second transmitters transmit simultaneously.

The invention claimed is:  
     
       1. A multi-mode wireless communication device, comprising:
 a first and a second receipt antenna configured to receive first and second radio frequency (RF) signals over a wireless channel;
 a first and a second receiver configured to process the first and second RF signals, respectively , to produce first and second digital samples; 
 
 an output module configured to receive the first and second digital samples and to reconstruct original data from the first and second digital samples; and
 a controller configured to evaluate a condition and to cause the first and second receivers, and the output module, to alternate between a predetermined protection mode, a predetermined spatial multiplexing mode, and a predetermined beam-forming mode based on the evaluated condition, wherein the predetermined protection mode includes deactivating the first receiver, and activating the second receiver from an inactive state, in response to a link failure associated with the first receiver. 
 
 
     
     
       2. The multi-mode wireless communication device of  claim 1 , wherein the condition is a product of a condition of the wireless channel and a quality of reception at the first and second receipt antennas. 
     
     
       3. The multi-mode wireless communication device of  claim 1 , wherein the predetermined protection mode involves communication of a single stream of data at any given instance, and adds redundancy to the multi-mode wireless communication device by causing the second receiver to serve as a backup to the first receiver. 
     
     
       4. The multi-mode wireless communication device of  claim 1 , wherein the first and second receivers receive first and second data substantially simultaneously when operating in the predetermined spatial multiplexing mode, and wherein the first data is different from the second data. 
     
     
       5. The multi-mode wireless communication device of  claim 1 , wherein the first receiver receives the first RF signal, carrying a first data, and the second receiver receives the second RF signal, carrying a second data, substantially simultaneously when operating in the predetermined beam-forming mode, wherein the second RF signal includes a phase shifted replica of the first RF signal, and wherein the first data is substantially identical to the second data. 
     
     
       6. The multi-mode wireless communication device of  claim 1 , wherein the first and second receipt antennas are each configured to receive the first RF signal transmitted by the first transmit antenna and the second RF signal transmitted by the second transmit antenna. 
     
     
       7. The multi-mode wireless communication device of  claim 1 , wherein the first and second receipt antennas are directional antennas having directional beam patterns, wherein main lobes of the directional beam patterns are directed towards an opposite end of the wireless channel. 
     
     
       8. The multi-mode wireless communication device of  claim 1 , wherein the first and second receivers are further configured to receive the first and second RF signals, respectively. 
     
     
       9. The multi-mode wireless communication device of  claim 8 , wherein the first RF signal has a first frequency and a first polarization, and wherein the second RF signal has a second frequency and a second polarization, which are different from the first frequency and the first polarization. 
     
     
       10. The multi-mode wireless communication device of  claim 1 , wherein the wireless channel includes a reverse channel, and wherein the controller is further configured to transmit data over the reverse channel. 
     
     
       11. A method for performing multi-mode wireless communication, comprising:
 receiving first and second radio frequency (RF) signals, over a wireless channel, at a dual reception device according to a first operational mode, wherein the first and second RF signals are received at a first and a second receipt antenna, located at the dual reception device; 
 evaluating one or more mode conditions; 
 determining when inefficient communication over the wireless channel exists based on the evaluated mode conditions; and 
 changing from the first operational mode to a second operational mode when inefficient communication over the wireless channel exists, wherein the first operational mode includes one of a predetermined protection mode, a predetermined spatial multiplexing mode, or a predetermined beam forming mode, and the second operational mode includes a different one of the predetermined protection mode, the predetermined spatial multiplexing mode, or the predetermined beam forming mode, and wherein the predetermined protection mode includes designating a link associated with the first receipt antenna as a primary link, and a link associated with the second receipt antenna as a backup link, and deactivating the primary link, and activating the backup link from an inactive state, in response to a failure of the primary link. 
 
     
     
       12. The method of  claim 11 , wherein the predetermined protection mode involves communication of a single stream of data at any given instance, and adds redundancy to the dual reception device by causing the second receipt antenna to serve as a back to the first receipt antenna. 
     
     
       13. The method of  claim 12 , further comprising:
 designating the backup link as a new primary link, and the primary link as a new backup link, in response to the failure of the primary link. 
 
     
     
       14. The method of method of  claim 11 , further comprising, when the second operational mode is the predetermined spatial multiplexing mode:
 activating first and second receivers, located at the dual reception device; 
 receiving both the first and second RF signals at the first and second receipt antennas; 
 processing, by the first and second receivers, the first and second RF signals, respectively, to produce first and second digital samples; and 
 performing a joint detection process of the first and second digital samples. 
 
     
     
       15. The method of  claim 14 , wherein the joint detection process is a Maximum Ratio Combining (MRC) process. 
     
     
       16. The method of  claim 11 , further comprising, when the second operational mode is the predetermined beam-forming mode:
 activating first and second receivers, located at the dual reception device; 
 receiving both the first and second RF signals at the first and second receipt antennas; 
 controlling a relative phase shift between the first and second RF signals by coordinating an operation of a first Local Oscillator (LO) and a second LO; 
 processing, by the first and second receivers, the first and second RF signals, respectively, to produce first and second digital samples; and 
 performing a joint detection process of the first and second digital samples. 
 
     
     
       17. The method of  claim 16 , wherein controlling the relative phase shift between the first and second RF signals includes locking the first LO to the second LO. 
     
     
       18. A wireless communication device for operating a predetermined protection mode, comprising:
 an input module configured to receive and process input data and to selectively output a data stream; 
 a primary transmitter configured to process the data stream, and to produce a first radio frequency (RF) signal; 
 a backup transmitter configured to process the data stream, and to produce a second RF signal; 
 a primary transmit antenna configured to transmit the first RF signal over a primary wireless channel ; 
 a backup transmit antenna configured to transmit the second RF signal over a backup wireless channel; and 
 a controller configured to instruct the input module to direct the data stream to the primary transmitter, and to activate the primary transmitter when the primary wireless channel is operational, and configured to instruct the input module to direct the data stream to the backup primary transmitter, and to activate the backup transmitter and deactivate the primary transmitter, when the primary wireless channel fails. 
 
     
     
       19. The wireless communication device of  claim 18 , wherein the primary wireless channel failure is caused by a failure in the primary transmitter or a condition change of the primary wireless channel. 
     
     
       20. The wireless communication device of  claim 18 , wherein the primary wireless channel and the backup wireless channel comprise a millimeter-wave link.