Simultaneous bidirectional transmission for radio systems

Abstract

Disclosed are methods, systems, and apparatus for maximizing the spectral efficiency of a communications spectrum by providing a means to transmit information continuously in both directions of a radio link on the same center frequency at any given time. One embodiment may be directed to a method of communicating in a point-to-point radio system. The method may include receiving a first signal at a first antenna of a radio head. The first signal may include a transmitted data signal and interfering signals. The method continues by determining a correction signal from a transmitter of the radio head and processing the first signal to remove the interfering signals using the correction signal, and sending a second signal using a second antenna. The first and second signals may be sent and received at substantially the same time.

We claim: 
     
         1 . A method of communicating in a point-to-point radio system, the method comprising:
 receiving a first signal at a first antenna of a radio head, wherein the first signal includes a transmitted data signal and interfering signals;   determining a correction signal from a transmitter of the radio head;   processing the first signal to remove the interfering signals using the correction signal; and   sending a second signal with the transmitter, which comprises a second antenna, wherein the first and second signals are sent and received at substantially the same time.   
     
     
         2 . The method of  claim 1 , wherein the correction signal is determined based at least in part on the second signal. 
     
     
         3 . The method of  claim 1 , wherein the first signal is received and the second signal is sent at the same frequency. 
     
     
         4 . The method of  claim 1 , wherein the first signal is received at a first frequency and the second signal is sent at a second frequency, wherein the first frequency and the second frequency are different, and wherein the correction signal is determined using a transmitter configured to operate at the first frequency. 
     
     
         5 . The method of  claim 4 , further comprising:
 receiving a third signal at the first antenna, wherein the third signal is received at the second frequency, wherein the third signal includes a second transmitted data signal and second interfering signals;   determining a second correction signal from a second transmitter of the radio head, wherein the second transmitter is configured to operate at the second frequency;   processing the third signal to remove a second interfering signals using the second correction signal;   sending a fourth signal using a third antenna, wherein the fourth signal is sent at the second frequency, wherein the first signal, second signal, third signal, and fourth signal are sent and received at substantially the same time.   
     
     
         6 . The method of  claim 1 , wherein the first antenna and the second antenna include one or more of a lens horn, a waveguide slot array, a continuous transverse stub array, or a trough guide array. 
     
     
         7 . The method of  claim 1 , wherein the first antenna and the second antenna are high isolation antennas. 
     
     
         8 . The method of  claim 1 , wherein the transmitter is a first transmitter, wherein the transmitted data signal is a first transmitted data signal, wherein the interfering signals are first interfering signals, wherein the correction signal is a first correction signal, and wherein the method further comprises:
 receiving a third signal at the first antenna of the radio head, wherein the third signal comprises a second transmitted data signal and second interfering signals, wherein the third signal has an orthogonal polarization from the first signal;   determining a second correction signal from a second transmitter of the radio head;   processing the third signal to remove the second interfering signals using the second correction signal; and   sending a fourth signal using a third antenna, wherein the fourth signal has an orthogonal polarization from the second signal, and wherein the first signal, the second signal, the third signal, and the fourth signal are sent and received at substantially the same time.   
     
     
         9 . The method of  claim 8 , wherein the first signal, the second signal, the third signal, and the fourth signal are sent and received at a first frequency, and wherein the method steps are repeated for signals having a second frequency, wherein a fourth antenna of the radio head receives two signals having orthogonally different polarizations at a second frequency, and wherein a fifth antenna and a sixth antenna are used to send two signals having orthogonally different polarizations at a second frequency. 
     
     
         10 . The method of  claim 9 , wherein all of the signals are sent and received at substantially the same time. 
     
     
         11 . The method of  claim 1 , wherein the radio head is a master radio head, and wherein the master radio head comprises two or more transmitters coupled to a gating block, wherein the gating block is configured to select one of the two or more transmitters to couple to a second antenna at a predetermined time, and wherein each of the two or more transmitters are configured to communicate with a particular slave radio head using the second antenna, and wherein determining the correction signal from the transmitter of the radio head further comprises:
 determining a correct transmitter from the two or more transmitters for a transmission time slot;   activating the correct transmitter from one of the two or more transmitters to couple to the second antenna; and   determining the correction signal from the activated transmitter coupled to the second antenna at the time of receiving the first signal.   
     
     
         12 . A radio head comprising:
 a receiver coupled to a first antenna;   a transmitter coupled to a second antenna; and   a processor coupled to the transmitter and the receiver, wherein the processor is configured to perform operations comprising:
 receiving a first signal from the first antenna, wherein the first signal includes a transmitted data signal and interfering signals; 
 determining a correction signal from the transmitter; 
 processing the first signal to remove the interfering signals using the correction signal; and 
 sending a second signal using the second antenna, wherein the first and second signals are sent and received at substantially the same time. 
   
     
     
         13 . The radio head of  claim 12 , wherein the correction signal is determined based at least in part on the second signal. 
     
     
         14 . The radio head of  claim 12 , wherein the first signal is received and the second signal is sent at the same frequency. 
     
     
         15 . The radio head of  claim 12 , wherein the first signal is received at a first frequency and the second signal is sent at a second frequency, wherein the first frequency and the second frequency are different, and wherein the correction signal is determined using a transmitter configured to operate at the first frequency. 
     
     
         16 . The radio head of  claim 15 , wherein the processor is configured to perform the method further comprising:
 receiving a third signal at the first antenna, wherein the third signal is received at the second frequency, wherein the third signal includes a second transmitted data signal and second interfering signals;   determining a second correction signal from a second transmitter of the radio head, wherein the second transmitter is configured to operate at the second frequency;   processing the third signal to remove a second interfering signals using the second correction signal; and   sending a fourth signal using a third antenna, wherein the fourth signal is sent at the first frequency, wherein the first signal, second signal, third signal, and fourth signal are sent and received at substantially the same time.   
     
     
         17 . The radio head of  claim 12 , wherein the first antenna and the second antenna include one or more of a lens horn, a waveguide slot array, a continuous transverse stub array, or a trough guide array. 
     
     
         18 . The radio head of  claim 12 , wherein the first antenna and the second antenna are high isolation antennas. 
     
     
         19 . The radio head of  claim 12 , wherein the transmitter is a first transmitter, wherein the transmitted data signal is a first transmitted data signal, wherein the interfering signals are first interfering signals, wherein the correction signal is a first correction signal, and wherein the method further comprises:
 receiving a third signal at the first antenna of the radio head, wherein the third signal comprises a second transmitted data signal and second interfering signals, wherein the third signal has an orthogonal polarization from the first signal;   determining a second correction signal from a second transmitter of the radio head;   processing the third signal to remove the second interfering signals using the second correction signal; and   sending a fourth signal using a third antenna, wherein the fourth signal has an orthogonal polarization from the second signal, and wherein the first signal, the second signal, the third signal, and the fourth signal are sent and received at substantially the same time.   
     
     
         20 . The radio head of  claim 19 , wherein the first signal, the second signal, the third signal, and the fourth signal are sent and received at a first frequency, and wherein the method steps are repeated for signals having a second frequency, wherein a fourth antenna of the radio head receives two signals having orthogonally different polarizations at a second frequency, and wherein a fifth antenna and a sixth antenna are used to send two signals having orthogonally different polarizations at a second frequency. 
     
     
         21 . The radio head of  claim 20 , wherein all of the signals are sent and received at substantially the same time. 
     
     
         22 . A master radio head comprising:
 a receiver coupled to a first antenna;   two or more transmitters coupled to a gating block, wherein the gating block is configured to select one of the two or more transmitters to couple to a second antenna at a predetermined time, and wherein each of the two or more transmitters are configured to communicate with a particular slave radio head using the second antenna; and   a processor coupled to the two or more transmitters and the receiver, wherein the processor is configured to perform operations comprising:
 receiving a first signal from the first antenna, wherein the first signal includes a transmitted data signal and interfering signals; 
 determining a correct transmitter from the two or more transmitters for a transmission time slot; 
 activating the correct transmitter from one of the two or more transmitters to couple to the second antenna; 
 determining a correction signal from the activated transmitter coupled to the second antenna at the time of receiving the first signal; 
 processing the first signal to remove the interfering signals using the correction signal; and 
 sending a second signal using the second antenna, wherein the first and second signals are sent and received at substantially the same time.