Multi radio access technology radio circuit

Patent metadata

Field	Value
Publication number	US-10277260-B2
Application number	US-201815889616-A
Country	US
Kind code	B2
Filing date	Feb 6, 2018
Priority date	Sep 12, 2017
Publication date	Apr 30, 2019
Grant date	Apr 30, 2019

Abstract

A multi radio access technology (RAT) radio circuit is provided. The multi RAT radio circuit can support concurrent transmission of radio frequency (RF) transmit signals modulated based on a first RAT and a second RAT and concurrent reception of RF receive signals modulated based on the first RAT and the second RAT. The multi RAT radio circuit splits each RF transmit signal into an in-phase transmit signal and a quadrature transmit signal. The determined phase offset is so configured such that the multi RAT radio circuit can effectively suppress an IMD(s) located above and below a transmit band(s) of the RF transmit signals. By suppressing the IMD(s), it is possible to improve RF performance of the multi RAT radio circuit regardless of whether the RF transmit signals and the RF receive signals are communicated in a contiguous or non-contiguous RF spectrum.

First claim

What is claimed is:

1. A multi radio access technology (RAT) radio circuit comprising:
a first transmit port and a second transmit port configured to receive a first transmit signal modulated based on a first RAT for transmission in a first transmit band and a second transmit signal modulated based on a second RAT for transmission in a second transmit band, respectively;
a first receive port and a second receive port each configured to output a first receive signal modulated based on the first RAT and a second receive signal modulated based on the second RAT, respectively;
first RAT circuitry configured to split the first transmit signal into a first in-phase transmit signal and a first quadrature transmit signal having a first phase offset relative to the first in-phase transmit signal; and
second RAT circuitry configured to split the second transmit signal into a second in-phase transmit signal and a second quadrature transmit signal having a second phase offset relative to the second in-phase transmit signal;
wherein the first phase offset and the second phase offset are determined such that the first RAT circuitry and the second RAT circuitry can suppress at least one predetermined intermodulation distortion (IMD) at the first receive port and the second receive port based on the first in-phase transmit signal, the first quadrature transmit signal, the second in-phase transmit signal, and the second quadrature transmit signal.

2. The multi RAT radio circuit of claim 1 further comprising:
a first antenna port configured to output the first transmit signal and receive the first receive signal; and
a second antenna port configured to output the second transmit signal and receive the second receive signal;
wherein the first phase offset and the second phase offset are determined such that the first RAT circuitry and the second RAT circuitry can suppress the at least one predetermined IMD at the first antenna port and the second antenna port based on the first in-phase transmit signal, the first quadrature transmit signal, the second in-phase transmit signal, and the second quadrature transmit signal.

3. The multi RAT radio circuit of claim 2 wherein:
the at least one predetermined IMD is a third order IMD (IMD3) located in a radio frequency (RF) spectrum lower than respective RF spectrums of the first transmit band and the second transmit band; and
the first phase offset and the second phase offset are each determined to be negative ninety degrees to suppress the IMD3 at the first receive port, the second receive port, the first antenna port, and the second antenna port.

4. The multi RAT radio circuit of claim 2 wherein:
the at least one predetermined IMD is a third order IMD (IMD3) located in a radio frequency (RF) spectrum higher than respective RF spectrums of the first transmit band and the second transmit band; and
the first phase offset and the second phase offset are determined to be positive ninety degrees and negative ninety degrees, respectively, to suppress the IMD3 at the first receive port, the second receive port, the first antenna port, and the second antenna port.

5. The multi RAT radio circuit of claim 2 wherein the first RAT circuitry is further configured to:
receive the first transmit signal from the first transmit port and split the first transmit signal into the first in-phase transmit signal and the first quadrature transmit signal;
receive a reflection of the second transmit signal from the first antenna port and generate a first in-phase reflection signal and a first quadrature reflection signal based on the reflection of the second transmit signal;
receive the first receive signal and the second receive signal concurrently from the first antenna port; and
generate the first in-phase receive signal and the first quadrature receive signal each comprising the first receive signal and the second receive signal.

6. The multi RAT radio circuit of claim 5 wherein:
the first in-phase receive signal comprises a first in-phase IMD generated by the first in-phase transmit signal and the first in-phase reflection signal;
the first quadrature receive signal comprises a first quadrature IMD generated by the first quadrature transmit signal and the first quadrature reflection signal; and
the first phase offset and the second phase offset are determined such that the first in-phase IMD and the first quadrature IMD are canceled at the first receive port.

7. The multi RAT radio circuit of claim 6 wherein the first RAT circuitry comprises:
a first transmit hybrid splitter coupled to the first transmit port and configured to split the first transmit signal into the first in-phase transmit signal and the first quadrature transmit signal;
a first quadrature amplifier circuit configured to amplify the first in-phase transmit signal and the first quadrature transmit signal;
a first hybrid splitter/combiner coupled to the first antenna port and configured to:
combine the first in-phase transmit signal and the first quadrature transmit signal into the first transmit signal such that the at least one predetermined IMD is suppressed in the first transmit signal;
provide the first transmit signal to the first antenna port for transmission in the first transmit band;
receive the reflection of the second transmit signal via the first antenna port;
generate the first in-phase reflection signal and the first quadrature reflection signal based on the reflection of the second transmit signal;
receive the first receive signal and the second receive signal concurrently via the first antenna port; and
generate the first in-phase receive signal and the first quadrature receive signal each comprising the first receive signal and the second receive signal; and

a first receive hybrid combiner coupled between the first receive port and the first hybrid splitter/combiner, the first receive hybrid combiner is configured to combine the first in-phase receive signal and the first quadrature receive signal to suppress the at least one predetermined IMD at the first receive port.

8. The multi RAT radio circuit of claim 7 wherein:
the first hybrid splitter/combiner is further configured to:
phase shift the first quadrature transmit signal by a positive ninety degrees prior to combining the first quadrature transmit signal with the first in-phase transmit signal;
phase shift the first quadrature reflection signal by a positive ninety degrees relative to the first in-phase reflection signal; and
phase shift the first quadrature receive signal by a positive ninety degrees relative to the first in-phase receive signal; and

the first receive hybrid combiner is further configured to phase shift the first quadrature receive signal by a positive ninety degrees.

9. The multi RAT radio circuit of claim 8 wherein the first RAT circuitry further comprises first filter circuitry provided between the first quadrature amplifier circuit and the first hybrid splitter/combiner, the first filter circuitry is configured to selectively pass through the first in-phase transmit signal, the first quadrature transmit signal, the first in-phase reflection signal, the first quadrature reflection signal, the first in-phase receive signal, and the first quadrature receive signal.

10. The multi RAT radio circuit of claim 9 wherein the first filter circuitry comprises:
a first in-phase transmit filter configured to pass through the first in-phase transmit signal;
a first in-phase receive filter configured to pass through the first in-phase reflection signal and the first in-phase receive signal;
a first quadrature transmit filter configured to pass through the first quadrature transmit signal; and
a first quadr

Assignees

• Qorvo Us Inc

Inventors

• Khlat Nadim
• Folkmann Andrew F

Classifications

• H04B1/0475 Primary

  with means for limiting noise, interference or distortion (H04B1/0483 takes precedence) · CPC title

• H04B1/1027

  assessing signal quality or detecting noise/interference for the received signal · CPC title

• H04W88/06

  adapted for operation in multiple networks {or having at least two operational modes}, e.g. multi-mode terminals · CPC title

• H04B1/40

  Circuits · CPC title

• H04B1/406 Primary

  with more than one transmission mode, e.g. analog and digital modes · CPC title