Radio with spatially-offset directional antenna sub-arrays
An intelligent backhaul radio that has an advanced antenna system for use in PTP or PMP topologies. The antenna system provides a significant diversity benefit. Antenna configurations are disclosed that provide for increased transmitter to receiver isolation, adaptive polarization and MIMO transmission equalization. Adaptive optimization of transmission parameters based upon side information provided in the form of metric feedback from a far end receiver utilizing the antenna system is also disclosed.
1. A radio comprising:
one or more demodulator cores, wherein each demodulator core is configured to demodulate at least one receive symbol stream;
a plurality of receive radio frequency (RF) chains, wherein each receive RF chain is configured to convert from a receive RF signal to a receive chain output signal;
one or more modulator cores, wherein each modulator core is configured to produce at least one transmit symbol stream;
a plurality of transmit radio frequency (RF) chains, wherein each transmit RF chain is configured to convert from a transmit chain input signal to a transmit RF signal;
a first directional antenna array comprising a plurality of first directional antenna sub-arrays, wherein each first directional antenna sub-array comprises a plurality of first directional antenna elements, and wherein each first directional antenna sub-array is coupled or couplable to at least one of the plurality of receive RF chains; and
a second directional antenna array comprising a plurality of second directional antenna sub-arrays, wherein each second directional antenna sub-array comprises a plurality of second directional antenna elements, and wherein each second directional antenna sub-array is coupled or couplable to at least one of the plurality of transmit RF chains;
wherein at least one first directional antenna sub-array is spatially offset relative to at least one other first directional antenna sub-array in a first arrangement; and
wherein said at least one first directional antenna sub-array is also spatially offset relative to at least one second directional antenna sub-array in a second arrangement.
2. The radio of claim 1 , wherein the first arrangement is horizontal and the second arrangement is vertical.
3. The radio of claim 1 , wherein the first arrangement is vertical and the second arrangement is horizontal.
4. The radio of claim 1 , wherein the first arrangement is diagonal in a first direction and the second arrangement is diagonal in a second direction.
5. The radio of claim 1 , wherein the radio is configured to transmit and receive coincident in time for at least a period of time.
6. The radio of claim 1 , further comprising:
a frequency selective receive path channel multiplexer, interposed between the one or more demodulator cores and at least the plurality of receive RF chains, wherein the frequency selective receive path channel multiplexer is configured to generate one or more receive symbol streams from at least a plurality of receive chain output signals;
a transmit path channel multiplexer, interposed between the one or more modulator cores and at least the plurality of transmit RF chains, wherein the transmit path channel multiplexer is configured to generate a plurality of transmit chain input signals from at least one or more transmit symbol streams.
7. The radio of claim 1 , wherein each one of the one or more demodulator cores comprises at least a decoder and a soft decision symbol demapper; and wherein each one of the plurality of receive RF chains comprises at least a vector demodulator and two analog to digital converters that are configured to produce the receive chain output signal as comprised of digital baseband quadrature signals.
8. The radio of claim 7 , wherein each one of the one or more modulator cores comprises at least an encoder and a symbol mapper; and wherein each one of the plurality of transmit RF chains comprises at least a vector modulator and two digital to analog converters that are configured to produce the transmit RF signal from the transmit chain input signals as comprised of digital baseband quadrature signals.
9. The radio of claim 8 , wherein each one of the one or more demodulator cores comprises at least one of a descrambler or a deinterleaver; and wherein each one of the one or more modulator cores comprises at least one of a scrambler or an interleaver.
10. The radio of claim 1 , further comprising:
a plurality of power amplifiers, wherein each power amplifier is configured to amplify at least one transmit RF signal, and wherein each power amplifier is couplable or coupled to at least one transmit RF chain and to at least one second directional antenna sub-array; and
a plurality of low noise amplifiers, wherein each low noise amplifier is configured to amplify at least one receive RF signal, and wherein each low noise amplifier is couplable or coupled to at least one receive RF chain and to at least one first directional antenna sub-array.
11. The radio of claim 1 , wherein the radio is configured to operate within a frequency range of between 2 GHz and 6 GHz.
12. The radio of claim 1 , wherein the radio is configured to operate within a frequency range of above 10 GHz.
13. The radio of claim 1 , wherein the radio is configured to use at least a Single-Carrier Frequency Domain Equalization (SC-FDE) modulation format.
14. The radio of claim 1 , wherein the radio is configured to use at least an Orthogonal Frequency Division Multiplexing (OFDM) modulation format.
15. The radio of claim 1 , wherein a total number of first directional antenna sub-arrays exceeds a number of receive symbol streams.
16. The radio of claim 1 , wherein a total number of first directional antenna sub-arrays exceeds a number of receive chain output signals.
17. The radio of claim 1 , wherein each of the plurality of first directional antenna elements and each of the plurality of second directional antenna elements comprises one of a patch antenna element, a slot antenna element, or a printed dipole antenna element.
18. The radio of claim 1 , wherein the first directional antenna array comprises at least a first one of the plurality of first directional antenna sub-arrays, said first one comprising a first number of first directional antenna elements, and at least a second one of the plurality of first directional antenna sub-arrays, said second one comprising a second number of first directional antenna elements, and wherein the first number is different than the second number.
19. The radio of claim 1 , wherein at least two transmit RF chains have respective transmit chain input signals derived from a single transmit symbol stream.
20. The radio of claim 1 , wherein at least two receive RF chains have respective receive chain output signals used to derive a single receive symbol stream.