CN106532276B

CN106532276B - Temperature compensation system and method for array antenna system

Info

Publication number: CN106532276B
Application number: CN201610772066.1A
Authority: CN
Inventors: 迈克尔·L·哈格曼; 拉塞尔·D·怀斯; 詹姆斯·B·韦斯特
Original assignee: Rockwell Collins Inc
Current assignee: Rockwell Collins Inc
Priority date: 2015-09-09
Filing date: 2016-08-30
Publication date: 2021-02-26
Anticipated expiration: 2036-08-30
Also published as: CN106532276A

Abstract

Systems and methods of compensating for temperature in a signal path of an antenna array are disclosed. The signal path includes an antenna element, a first phase shifter or time delay unit, and a first variable gain power amplifier. Systems and methods may provide a local temperature signal, a remote temperature signal, and at least one of the local temperature signal and the remote temperature signal to a slope control circuit and provide a phase control signal or a gain control signal using the slope control circuit at least partially in response to the local temperature signal, the remote temperature signal, and the at least one of the local temperature signal and the remote temperature signal.

Description

Temperature compensation system and method for array antenna system

Cross reference to related patent applications

This application relates to U.S. application serial No. 14/788360 filed by West et al on day 6/30 2015, U.S. application serial No. 14/300021 filed by West et al on day 6/2014, U.S. application serial No. 14/300074 filed by West et al on day 6/2014, and U.S. application serial No. 14/300055 filed by West et al on day 6/6 2014, all assigned to the assignee of the present application and hereby incorporated herein by reference in their entirety.

Background

The present disclosure relates generally to the field of antenna systems. More particularly, the present disclosure relates generally to the field of antenna arrays, including but not limited to phased array antenna systems or Electronically Scanned Array (ESA) antenna systems, such as Active Electronically Scanned Array (AESA) antenna systems.

An antenna array is utilized with a transceiver. As used in this application, the term "transceiver" refers to an electronic device embodied as a transmitter, a receiver, or a transmitter/receiver. The antenna array may be steered by using phase shifters and amplifiers coupled to respective antenna elements in the antenna array to steer the antenna at the aiming angle. The phase shifter may be a variable phase shifter that provides a set of phase delays in response to a set of commands that direct the antenna to the appropriate aiming angle without physically moving the antenna element.

Temperature variations can affect the accuracy and gain control of the phases in the antenna array and thus affect the accuracy of beam positioning and beam symmetry. Certain applications, such as radar systems, terrestrial communication systems, satellite communication systems, sensors, etc., are particularly sensitive to errors in phase and amplitude control. Therefore, temperature independent phase and gain control in antenna arrays is desired to reduce errors in phase and amplitude control.

Conventional antenna arrays have attempted temperature compensation at the level of subcircuitry elements within the signal path. However, not all sub-circuit elements are capable of having an automatic temperature compensation circuit, and compensating each element in the transmit and receive chains is difficult to provide. Furthermore, process variations can cause non-uniform temperature variations in each sub-circuit element, the compensation of which is difficult on a sub-circuit element basis. In addition, such conventional compensation systems increase the size, cost, power, and weight of the antenna array.

Accordingly, there is a need for a method of compensating for temperature variations in an antenna system that does not significantly increase the size, cost, power, and/or weight of the transceiver or antenna system. Furthermore, there is a need for an antenna system with temperature compensation of the signal path between the antenna element and the divider. Still further, there is a need for a robust AESA-based or other phased array antenna-based system with in-situ temperature compensation. Still further, there is a need for an AESA-based or other phased array antenna-based system with real-time temperature compensation of separate receive and transmit chains. Still further, there is a need for an AESA-based or other phased array antenna-based system that compensates for gain variations due to temperature variations. Still further, there is a need for an AESA-based or other phased array antenna-based system that compensates for phase changes due to temperature changes. Still further, there is a need for a robust temperature compensation scheme located at each transmit and/or receive channel in an antenna array.

SUMMARY

In one aspect, the inventive concepts disclosed herein are directed to a system that compensates for temperature in a signal path of an antenna array. The signal path includes an antenna element, a first phase shifter or time delay unit, and a first variable gain power amplifier. The system provides the local temperature signal, the remote temperature signal, and at least one of the local temperature signal and the remote temperature signal to the slope control circuit and uses the slope control circuit to provide the phase control signal or the gain control signal at least partially in response to the local temperature signal, the remote temperature signal, and the at least one of the local temperature signal and the remote temperature signal.

In another aspect, the inventive concepts disclosed herein are directed to an antenna system. The antenna system includes a signal path; each signal path includes an antenna element, a phase shifter or time delay unit, a first variable gain power amplifier, and a temperature compensation circuit. The temperature compensation circuit includes a slope control circuit and a temperature variable gain amplifier. A temperature variable gain amplifier, a first variable gain power amplifier, an antenna element, a phase shifter, and a variable gain power amplifier are arranged in series in each signal path. The slope control circuit is configured to receive the first temperature signal and provide a gain control signal to the temperature variable gain amplifier to compensate for gain variations due to temperature variations in the signal path.

In another aspect, the inventive concepts disclosed herein are directed to a method of compensating for temperature in a signal path of an antenna array. The signal path includes an antenna element, a first phase shifter or time delay unit, and a first variable gain power amplifier. The method includes providing a temperature signal to a slope control circuit of a second variable gain control amplifier in the signal path, and providing a gain control signal using the slope control circuit at least partially in response to the temperature signal.

In yet another aspect, the inventive concepts disclosed herein are directed to a method of compensating for temperature in a signal path of an antenna array. The signal path includes an antenna element, a first phase shifter or time delay unit, and a first variable gain power amplifier. The method includes providing a local temperature signal, a remote temperature signal, and at least one of the local temperature signal and the remote temperature signal to a slope control circuit. The method also includes providing a phase control signal to a second phase shifter or providing a time delay control signal to a second time delay unit in the signal path using a slope control circuit at least partially in response to the local temperature signal, the remote temperature signal, and at least one of the local temperature signal and the remote temperature signal.

Brief description of the drawings

Embodiments of the inventive concepts disclosed herein will be more fully understood from the following detailed description when read in conjunction with the accompanying drawings, wherein like reference numerals refer to like elements, and in which:

fig. 1 is a block diagram of an antenna system including a signal path with temperature compensation and beam steering circuitry in accordance with some embodiments of the inventive concepts disclosed herein;

fig. 2A is a more detailed block diagram of a transmit signal path with temperature compensation for the transceiver shown in fig. 1, in accordance with some embodiments of the inventive concepts disclosed herein;

fig. 2B is a more detailed block diagram of a receiver path with temperature compensation for the transceiver shown in fig. 1 in accordance with some embodiments of the inventive concepts disclosed herein;

fig. 3A is a more detailed block diagram of a transmit signal path with temperature compensation for the transceiver shown in fig. 1, in accordance with some embodiments of the inventive concepts disclosed herein;

fig. 3B is a more detailed block diagram of a receive path with temperature compensation for the transceiver shown in fig. 1 in accordance with some embodiments of the inventive concepts disclosed herein;

FIG. 4 is a graph illustrating a gain parameter versus temperature for the signal path shown in FIG. 2 in accordance with some embodiments of the inventive concepts disclosed herein;

FIG. 5 is a graph illustrating a phase parameter versus temperature of the signal path shown in FIG. 3 in accordance with some embodiments of the inventive concepts disclosed herein;

FIG. 6 is a graph illustrating device temperature versus temperature relationships associated with the radio frequency signals of the signal paths shown in FIG. 3, in accordance with some embodiments of the inventive concepts disclosed herein;

FIG. 7 is a graph illustrating radio frequency power versus time associated with the radio frequency signal associated with the device temperature response shown in FIG. 6, in accordance with some embodiments of the inventive concepts disclosed herein;

FIG. 8 is a graph illustrating a phase versus time relationship associated with a radio frequency signal associated with the device temperature response shown in FIG. 6 in accordance with some embodiments of the inventive concepts disclosed herein; and

fig. 9 is a diagram of an operational flow of temperature compensation of the signal path shown in fig. 1, according to some embodiments of the inventive concepts disclosed herein.

Detailed Description

Before describing in detail embodiments of the inventive concepts disclosed herein, it should be observed that the inventive concepts disclosed herein include, but are not limited to, novel structural combinations of components and circuits, and are not limited to specific detailed configurations thereof. Accordingly, the structure, method, function, control, and arrangement of components and circuits are primarily illustrated in the drawings by readily understandable block representations and schematic diagrams, so as not to obscure the disclosure with structural details that will be readily apparent to those skilled in the art having the benefit of the description herein. Furthermore, the inventive concepts disclosed herein are not limited to the specific embodiments depicted in the exemplary drawings, but are to be interpreted according to the language of the claims.

Referring generally to the drawings, a transceiver and antenna system that may be used in radar, sensor and communication systems is shown and described. The transceiver and antenna system may utilize an antenna array (e.g., an electrically steerable antenna array). For example, the systems and methods may be utilized in communication, sensing, and/or radar systems such as military or weather radar systems, electronic intelligence (ELINT) receivers, Electronic Counter Measurement (ECM) systems, Electronic Support Measurement (ESM) systems, targeting systems, or other systems. In some embodiments, systems and methods are used to provide an ultra-wideband (UWB) system. The steerable antenna array may include, but is not limited to, a phased array antenna system, an electronically scanned array antenna system, or an Electronically Scanned Array (ESA) antenna system, such as an Active Electronically Scanned Array (AESA) antenna system.

In some embodiments, phase and/or amplitude compensation with respect to temperature is provided within a signal path or cascade between the antenna element and the transceiver. In some embodiments, total temperature compensation is performed at one location in each transmitter or receiver signal path. In some embodiments, a temperature compensation circuit in each signal path corrects the gain and/or insertion phase imperfections as a function of temperature for the entire transmit or receive chain. In some embodiments, chain-level temperature compensation advantageously removes topology complexity from the chain sub-circuits and locates temperature compensation in the signal path. In some embodiments, a temperature compensation circuit is used in the signal path and is a high speed analog processor.

Referring to fig. 1, the system 10 includes an antenna system 12, a transceiver 14, beam steering circuitry 16, and a remote temperature sensor 19. In some embodiments, system 10 operates in a receive mode, a transceiver mode, or a transmit mode. The beam steering circuitry 16 may be provided within the antenna system 12, the transceiver 14, or as a separate system. In some embodiments, portions of the beam steering circuitry 16 are integrated with the antenna system 12, while other portions of the beam steering circuitry 16 are integrated with the transceiver 14.

The system 10 may be or may be part of a sensing system, a radar system, and a communication system. In some embodiments, the system 10 may be part of an electronic intelligence (ELINT) receiver, an Electronic Countermeasure (ECM) system, a weather radar system, an Electronic Support Measurement (ESM) system, and/or a hybrid thereof.

In some embodiments, system 10 may use the multichip modules discussed in U.S. applications serial No. 13/760,964 filed on 6.2.2013, serial No. 13/781,449 filed on 28.2.2013, and serial No. 13/837,934 filed on 15.3.3.2013, all of which are incorporated herein by reference in their entirety. In some embodiments, system 10 may include components described in U.S. application No. 13/714,209 filed 12/13/2012 and application No. 13/737,777 filed 1/9/2013. In some embodiments, system 10 may include components described in U.S. application serial No. 14/788360 filed on 30.6.2015 by West et al, which is incorporated herein by reference in its entirety.

In some embodiments, the antenna system 12 may be a two-dimensional array or a single-dimensional array. In some embodiments, the antenna system 12 is used to electronically point at an angle in one or two dimensions. For example, a beam may be aimed by an antenna system (e.g., an AESA antenna) by transmitting waves that constructively interfere at certain angles in front of the antenna system 12. In some embodiments, the antenna system 12 includes various components including apertures, power amplifiers, low noise amplifiers, phase shifters, transmit/receive converters, temperature sensing devices, Radio Frequency (RF) power and phase delay sensing components, digital control and beam steering computers. In some embodiments, the two-dimensional array or the single-dimensional array of antenna systems 12 is circular, cylindrical, spherical, etc., and may be any curved surface, conformal to the surface of the vehicle, etc.

In certain embodiments, the antenna system 12 may be embodied as a Balanced Antipodal Vivaldi Array (BAVA) aperture or other antenna system. In some embodiments, array elements 20 are embodied as dual polarized arrays, such as the array shown in U.S. patent No. 8,466,846, which is incorporated by reference herein in its entirety.

The antenna system 12 includes a signal path 18 and a set of power dividers 24. The signal paths 18 each include an antenna element 20, a phase shifter 22, an amplifier 23, and a temperature compensation circuit 25. In some embodiments, each antenna element 20 is associated with a respective phase shifter 22 and amplifier 23. The phase shifter 22 and the amplifier 23 are controlled by the beam control circuit 16 including a slope control circuit 36. In some embodiments, radio frequency amplifiers, such as amplifier 23, may be disposed before and after phase shifter 22.

The power splitter 24 may be arranged in various ways to communicate signals between the element 20 and the transceiver 14. In some embodiments, the power splitter 24 is a power splitter or a directional coupler. In some embodiments, the power splitter 24 is a passive component.

The phase shifter 22 and the amplifier 23 are a vector modulator based phase shifter and a variable gain amplifier, respectively, and implement a set of phase shifts or phase delays and amplifier gains, respectively, such that a suitable constructive interference is obtained. A set of control signals or commands may be provided from beam steering circuitry 16 to control inputs on phase shifters 22 and amplifiers 23. The control commands set the appropriate phase shift of the phase shifter 22 and the gain of the amplifier 23 to point the antenna system 12 at the aiming angle. In some embodiments, amplifiers 23 each comprise two or more amplifiers.

The temperature compensation circuit 25 is an analog processor configured to adjust the gain or phase in response to a locally measured temperature, in response to a remotely measured temperature, or in response to both a locally measured temperature and a remotely measured temperature. The locally measured temperature is related to a measurement made on the integrated circuit associated with the signal path 18. In some embodiments, the remotely measured temperature is provided by a remote temperature sensor 19. In some embodiments, temperature compensation circuit 25 uses one or more internal variable gain amplifiers for gain adjustment and one or more internal variable phase shifters for phase adjustment. In some embodiments, temperature compensation circuit 25 uses amplifier 23 in its signal path 18 for gain adjustment and phase shifter 22 in its signal path 18 for phase adjustment.

In some embodiments, the temperature compensation circuit 25 is an analog processor configured to adjust gain or phase in response to a gain or phase slope temperature compensation function or operation. The gain or slope compensation operation adapts the gain or phase response of the signal path 18 to be relatively flat with respect to temperature. In some embodiments, a slope control word (slope control word) is provided by beam control circuitry 16 to adjust the slope operation for gain or phase (e.g., in some embodiments, temperature compensation circuitry 25 has programmable phase or gain control without regard to the analog processor). In some embodiments, the slope control word is provided by beam steering circuitry 16 and determined by calibration tests. Calibration tests may be performed after assembly of the system 10, where temperature changes are measured locally and remotely, and the gain and phase response of each signal path 18 is characterized with respect to temperature.

In some embodiments, the slope control word may be based on experimental data relating to remote and local temperature readings. The slope control word advantageously allows the temperature compensation circuit 25 to be designed for various types of signal paths and transceivers. The slope control word also advantageously allows the temperature compensation circuit 25 to accommodate process variations with respect to temperature-affected phase and gain responses.

In some embodiments, temperature compensation circuit 25 is a high-speed circuit capable of gain and/or phase adjustments within 100 nanoseconds, within 50 nanoseconds, or within tens of nanoseconds. In some embodiments, the temperature compensation circuit 25 adjusts to meet the waveform requirements for the radar within 500 nanoseconds. For example, in some embodiments, applications using pulse-to-pulse beam steering, dynamic pattern synthesis, and high-rate transmit-receive switching benefit from fast response times. The analog nature of the temperature compensation circuit 25 makes it more suitable for high speed regulation than digital loop techniques with slower response times.

In some embodiments, the phase shifter 22, the amplifier 23, the antenna element 20, and the temperature compensation circuit 25 in each signal path 18 are coupled in series. The phase shifter 22, the amplifier 23, and the temperature compensation circuit 25 are integrated on a gallium arsenide, gallium nitride, or silicon germanium substrate. The order of the phase shifter 22, the amplifier 23, the antenna element 20 and the temperature compensation circuit 25 in each signal path 18 is not shown in a limiting manner. In some embodiments, additional elements or less than all of the elements shown in fig. 1 are provided in the signal path. In some embodiments, phase shifter 22 is replaced by a time delay circuit such as those discussed in U.S. patent application No. 14/300055, which is incorporated by reference herein in its entirety.

In some embodiments, the transceiver 14 is disposed on one or more RF integrated circuits or modules. The transceiver 14 includes an up/down converter 30, analog-to-digital converter/digital-to-analog converter circuitry 32 and an operations processor 34. The signal is transmitted to the antenna system 12 through the up/down converter and received from the antenna system 12. In some embodiments, up/down converter 30 up-converts the transmitted signal from converter circuit 32 to and down-converts the signal received from antenna system 12. In some embodiments, signals for transmission from the operations processor 34 are converted to analog signals in the converter circuit 32 of the frequency converter 30. In some embodiments, the received signal from frequency converter 30 is converted to a digital signal in converter circuit 32 of operation processor 34.

The transceiver 14 may be a receiver only, a transmitter only, or both a transmitter/receiver. The transceiver 14 may be embodied as a hardwired circuit, an ASIC, a programmable logic device, an operating processor, or a combination thereof.

The beam steering circuit 16 may be a software module operating on a computer platform or operations processor 34, an ASIC, a programmable logic device, a hard disk circuit, or a mixture thereof. In some embodiments, beam steering circuitry 16 provides a set of phase shift commands to phase shifter 22 and gain commands to amplifier 23 to achieve the aiming angle. In some embodiments, the set of phase shift commands and gain commands are provided in response to a beam aiming angle parameter and a frequency parameter. In some embodiments, the set of phase shift commands and gain commands are provided in response to a beam aiming angle parameter, an environmental parameter, and a frequency parameter.

In some embodiments, the remote temperature sensor 19 is physically separate from the signal path 18. In some embodiments, the signal of the remote temperature sensor 19 is proportional to the absolute temperature. In some embodiments, the remote temperature sensor 19 is disposed external to the chip or integrated circuit package associated with the signal path 18. In some embodiments, the remote temperature sensor 19 is integrated with the beam steering circuitry 16 or is part of the beam steering circuitry 16. In some embodiments, the remote temperature sensor 19 senses the temperature at the ASEA board level.

Referring to fig. 2A-B,

signal paths

18a and 19a are similar to signal path 18 (fig. 1) and are between antenna element 20 and node 40 associated with divider 24. The antenna element 20 is optional in some embodiments. Referring to fig. 2A, signal path 18a may be a transmit path. Signal path 18a includes a phase shifter 22 or time delay element, an amplifier 23, a temperature compensation circuit 25a (e.g., similar to temperature compensation circuit 25), and an antenna element 20. Amplifier 70 is coupled in series with phase shifter 22. Amplifier 70 is a power amplifier coupled between phase shifter 22 and antenna element 20 in signal path 18 a.

Referring to fig. 2B, signal path 19a is similar to signal path 18 (fig. 1) and is configured as a receive path. The signal path 19a includes a phase shifter 22 or time delay unit, an amplifier 23, a temperature compensation circuit 25a (e.g., similar to the temperature compensation circuit 25), and an antenna element 20. Amplifier 70 is a low noise amplifier coupled between node 40 in signal path 19a and phase shifter 22.

Referring to fig. 2A-B, amplifier 70 may be an off-chip or on-chip device having a different temperature profile relative to other components in

signal path

18a or 19 a. In some embodiments, amplifier 70 may be coupled to temperature compensation circuit 25a instead of phase shifter 22. The amplifier 70 has a slave bias control input 72 coupled to a slave bias control output 74 of the amplifier 23. In some embodiments, amplifier 70 is optional.

The temperature compensation circuit 25 includes a slope control circuit 60a, a variable gain amplifier 62 and a local temperature sensor 64. Slope control circuit 60a receives a local temperature signal from local temperature sensor 64 and a remote temperature signal from remote temperature sensor 19 and provides a gain control signal to variable gain amplifier 62 to adjust the gain of

signal path

18a or 19a to remove or mitigate gain variations due to temperature variations. In some embodiments, the slope control circuit 60a uses only one of the remote temperature signal or the local temperature signal. In some embodiments, the signal of the local temperature sensor 64 is proportional to absolute temperature and is integrated with the temperature compensation circuit 25. In some embodiments, the remote temperature sensor 19 is integrated with the amplifier 70.

Referring to fig. 3A, signal path 18b is similar to signal path 18 (fig. 1) and is between antenna element 20 and a node 40 associated with divider 24. Signal path 18b may be a transmit path as shown in fig. 3A. Signal path 18b includes phase shifter 22 or time delay unit, amplifier 23, phase shifter 76, temperature compensation circuit 25b (e.g., similar to temperature compensation circuit 25), and antenna element 20. Referring to fig. 3B, signal path 19B is similar to signal path 18 (fig. 1) and is between antenna element 20 and node 40 associated with divider 24. The signal path 19B may be a receive path as shown in fig. 3B. Signal path 19b includes phase shifter 22 or time delay unit, amplifier 23, phase shifter 76, temperature compensation circuit 25b (e.g., similar to temperature compensation circuit 25), and antenna element 20.

Referring to fig. 3A-B, temperature compensation circuit 25B may adjust one or both of the phase or gain associated with signal paths 18B and 19B. In some embodiments, phase shifter 76 is a vector modulator-based phase shifter. In some embodiments, amplifier 80 is coupled in series with phase shifter 22 and phase shifter 76. In signal path 18b (fig. 3A), amplifier 70 is a power amplifier coupled between phase shifter 22 and antenna element 20. In signal path 19B (fig. 3B), amplifier 70 is a low noise amplifier coupled between phase shifter 22 and antenna element 20. In some embodiments, amplifier 80 is an off-chip device or an on-chip device relative to the chip associated with phase shifter 22, temperature compensation circuit 25, and amplifier 23. In some embodiments, amplifier 80 is a transmit amplifier in signal path 18b and a receive amplifier in signal path 19b and is optional. In some embodiments, the remote temperature sensor 19 is integrated with the amplifier 80.

The temperature compensation circuit 25 includes a slope control circuit 60b, a variable gain amplifier 62, a local temperature sensor 64, and a phase shifter 76. Slope control circuit 60b receives a local temperature signal from local temperature sensor 64 and a remote temperature signal from remote temperature sensor 19 and provides a gain control signal to variable gain amplifier 62 to adjust the gain of

signal path

18b or 19b to remove or mitigate gain variations due to temperature variations. In some embodiments, the slope control circuit 60 uses only one of the remote temperature signal or the local temperature signal.

Slope control circuit 60b receives a local temperature signal from local temperature sensor 64 and a remote temperature signal from remote temperature sensor 19 and provides a phase control signal to phase shifter 76 to adjust the phase of

signal path

18b or 19b to remove or mitigate phase changes due to temperature changes. In some embodiments, the phase shifter 76 is a time delay unit controllable to provide a time delay in response to a time delay control signal provided by the slope control circuit 60 b. In some embodiments, the slope control circuit 60 may activate the selected delay path to provide appropriate adjustment of the time delay using the time circuit described in U.S. patent application No. 14/300055, which is incorporated by reference herein in its entirety. In some embodiments, the slope control circuit 60b uses only one of the remote temperature signal or the local temperature signal. In some embodiments, the slope control circuit 60b adjusts only one of the gain or phase in response to temperature. The phase shifter 76 and the amplifier 62 as well as the local temperature sensor 64 and the remote temperature sensor 19 have a response time of less than 100 nanoseconds, in the range of 50 nanoseconds or tens of nanoseconds.

Referring to fig. 4, graph 400 includes a Y-axis 402 representing gain in signal path 18a (fig. 2) and an X-axis 404 representing temperature. In some embodiments, the temperature range is between-55 and 155 degrees Celsius. Line 406 represents the uncorrected gain versus temperature in

signal path

18a or 19 a. Line 408 represents the corrected gain versus temperature in

signal path

18a or 19 a. In some embodiments, slope control circuit 60a applies a function of the conversion gain response to the temperature associated with line 406 to coincide with line 408. In some embodiments, a slope control word may be used to set the appropriate slope for such a transition. In some embodiments, line 406 of signal path 18a may be determined during calibration. The gain in signal path 18B or 19B (fig. 3A-B) may be similarly corrected.

Referring to fig. 5, a graph 500 includes a Y-axis 502 representing phase in the signal path 18b (fig. 3) and an X-axis 504 representing temperature. Line 506 represents the uncorrected phase versus temperature in

signal path

18b or 19 b. Line 508 represents the corrected phase versus temperature in

signal path

18b or 19 b. In some embodiments, slope control circuit 60b applies a function of the switching phase response to the temperature associated with line 506 to coincide with line 508. In some embodiments, a slope control word may be used to set the appropriate slope for such a transition. In some embodiments, line 506 of signal path 18b may be determined during calibration.

Although

lines

406 and 506 are linear in fig. 4 and 5, other responses are possible, including but not limited to curves, parabolic step functions, and other polynomial functions. In some embodiments, a curve fitting algorithm may be used to calculate a slope control word for the transition temperature response.

Referring to FIG. 6, graph 600 includes a Y-axis 602 representing device temperature (e.g., temperature associated with path 18b (FIG. 3)) and an X-axis 604 representing time. The device temperature is related to the localized heating of the devices associated with

signal paths

18, 18a-b, and 19 a-b. Referring to fig. 7, graph 700 includes a Y-axis 702 representing radio frequency signal power in signal path 18b (fig. 3) and an X-axis 704 representing time. Line 608 (fig. 6) represents temperature versus time when the rf pulse associated with line 710 is provided in

signal path

18b or 19 b. Line 710 represents the power of the radio frequency signal versus time. In some embodiments, the pulse length is less than 500 nanoseconds. As the rf pulse (represented by line 710) is provided, the device temperature (e.g., line 608) increases over time and returns to normal temperature once the rf pulse is no longer provided. In some embodiments, the power of the radio frequency pulses is decreased in response to an increase in temperature (e.g., due to gain variations). Accordingly, in some embodiments, the automatic heating in signal path 18 is regulated by slope control circuit 60a through a fast response to temperature.

Referring to fig. 8, a graph 800 includes a Y-axis 802 representing the phase of the radio frequency signal in signal path 18B or 19B (fig. 3A-B) and an X-axis 804 representing time. Line 812 represents the phase versus time when the rf pulse associated with line 710 is provided in signal path 18 b. The phase represented by line 812 increases as the temperature of the device represented by line 608 increases.

As shown in fig. 6-8, the insertion phase and gain are functions of the temperature of the devices in the

signal paths

18, 18a, and 18b, such as silicon germanium variable gain amplifiers and phase shifters, and gallium arsenide and gallium nitride power amplifiers. The use of

temperature compensation circuits

25, 25a and 25b in the

respective signal paths

18, 18a, 18b, 19a and 19b allows different small signal and drive dependent gains and phase temperature dependencies to be accommodated at lower cost.

Referring to fig. 1-3 and 9, the system 10 may utilize an operational flow 900. In some embodiments, the flow 900 may be performed for each signal path 18 shown in fig. 1.

At operation 902, a slope command may be provided to the temperature compensation circuit 25. The slope command may define adjustments to gain, phase, or both gain and phase with respect to the temperature of the signal path 18. At operation 904, the phase and gain of the signal path may be set using digital phase shift commands from the beam steering circuitry 16.

At operation 908, the temperature compensation circuit 25 receives the local temperature signal, the remote temperature signal, and at least one of the local temperature signal and the remote temperature signal. The temperature signal may be provided by the remote temperature sensor 19 (fig. 2) or the local temperature sensor 64. In some embodiments, using both local temperature signals and remote temperature sensor signals allows for more precise adjustment in signal paths 18a (fig. 2A) and 18b (fig. 3A) or signal paths 19a (fig. 2A) and 19b (fig. 3A). The slope control circuits 90a and 90b may make gain and/or phase adjustments in real time in response to remote and local temperature values based on experimental remote temperature responses and experimental local temperature responses. In some embodiments, the temperature changes in response to self-heating due to the radio frequency signal in the signal path 18.

At operation 908, in some embodiments, the temperature compensation circuit 25 (fig. 1) adjusts the gain or phase of the signal path 18 such that the response of the gain, phase, or both the gain and phase with respect to temperature is relatively flat. The slope control circuit 60a (fig. 2) or 60b (fig. 3) may provide an adjustment or control signal to the amplifier 62 or the phase shifter 66 to effect a gain or phase adjustment in response to the local temperature signal, the remote temperature signal, and at least one of the local temperature signal and the remote temperature signal.

The construction and arrangement of the systems and methods as shown in the various exemplary embodiments are illustrative only. Although only a few embodiments have been described in detail in this disclosure, many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, orientations, etc.). For example, the position of elements may be reversed or otherwise varied, and the nature or number of discrete elements or positions may be altered or varied. Accordingly, all such modifications are intended to be included within the scope of the inventive concepts disclosed herein. The order or sequence of any operational flow or method operations may be varied or re-sequenced according to alternative embodiments. Other substitutions, modifications, changes and omissions may be made in the design, operating conditions and arrangement of the exemplary embodiments without departing from the broad scope of the inventive concepts disclosed herein.

The present disclosure contemplates methods, systems, and program products on any machine-readable media for performing various operations. Embodiments of the inventive concepts disclosed herein may be implemented using existing computer operating flows, or by special purpose computer operating flows for appropriate systems that are combined for this or another purpose, or by hardwired systems. Embodiments within the scope of the inventive concepts disclosed herein include program products comprising machine-readable media for carrying or having machine-executable instructions or data structures stored thereon. Such machine-readable media can be any available media that can be accessed by a special purpose computer or other machine with an operational flow. By way of example, such machine-readable media can comprise RAM, ROM, EPROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to carry or store desired program code in the form of machine-executable instructions or data structures and which can be accessed by a general purpose or special purpose computer or other machine with an operational flow. When information is transferred or provided over a network or another communications connection (either hardwired, wireless, or a combination of hardwired or wireless) to a machine, the machine properly views the connection as a machine-readable medium. Thus, any such connection is properly termed a machine-readable medium. Combinations of the above are also included within the scope of machine-readable media. Machine-executable instructions comprise, for example, instructions and data which cause a special purpose computer or special purpose operational flow machine to perform a certain function or group of functions.

Claims

1. An antenna system, comprising:

a remote temperature sensor configured to provide a remote temperature signal;

a plurality of signal paths, wherein each signal path comprises:

a local temperature sensor configured to provide a local temperature signal indicative of a temperature in one of the signal paths, wherein the remote temperature signal is indicative of a temperature outside the signal path;

an antenna element;

a phase shifter or time delay unit;

a variable gain power amplifier; and

a temperature compensation circuit comprising a slope control circuit and a temperature variable gain amplifier; and is

Wherein the temperature variable gain amplifier, the antenna element, the phase shifter, and the variable gain power amplifier are arranged in series in the signal path of the plurality of signal paths, wherein the slope control circuit is configured to receive the remote temperature signal and the local temperature signal and provide a gain control signal to the temperature variable gain amplifier to compensate for gain variations due to temperature variations in the signal path.

2. The system of claim 1, wherein the temperature compensation circuit is an analog signal processor having a response time to temperature correction of under 100 nanoseconds.

3. The system of claim 2, wherein the temperature compensation circuit is an analog signal processor having a response time to temperature correction below 30 nanoseconds.

4. The system of any of claims 1 to 3, wherein the remote temperature sensor is not integrated with an integrated circuit for the temperature compensation circuit.

5. The system of claim 4, wherein the remote temperature sensor is integrated with a power amplifier.

6. The system of claim 5, wherein the remote temperature signal is proportional to absolute temperature.

7. The system of claim 6, wherein the local temperature sensor is integrated with an integrated circuit in the signal path.

8. The system of any of claims 1 to 3, wherein the temperature compensation circuit further comprises a temperature dependent phase shifter or a time delay element, and the slope control circuit is configured to provide a phase control signal to the temperature dependent phase shifter or a time delay control signal to the time delay element to compensate for phase changes due to the temperature changes in the signal path.

9. The system of claim 8, wherein the local temperature sensor is integrated with the temperature compensation circuit.

10. The system of any one of claims 1 to 3, wherein the beam steering circuit is configured to provide a gain control signal to the variable gain amplifier and a phase control signal to the phase shifter to control the gain of the variable gain amplifier and the phase of the phase shifter to achieve beam steering.

11. A method of compensating for temperature in a signal path of an antenna array, the method comprising:

providing a remote temperature signal and a local temperature signal to a slope control circuit in the signal path, the signal path including an antenna element, a first phase shifter or time delay unit, and a first variable gain power amplifier, the local temperature signal indicative of a local temperature in the signal path, and the remote temperature signal indicative of a remote temperature outside the signal path; and

providing a gain control signal to a second variable gain control amplifier in the signal path using the slope control circuit at least partially in response to the remote temperature signal and the local temperature signal.

12. The method of claim 11, further comprising providing a phase control signal to a second phase shifter in the signal path using the slope control circuit at least partially in response to at least one of the remote temperature signal, the local temperature signal, or both the remote temperature signal and the local temperature signal.

13. The method of claim 11 or 12, wherein the slope control circuit is an analog processor that provides the gain control signal to flatten the signal path gain with temperature.

14. The method of claim 11 or 12, wherein the remote temperature signal is provided by an integrated circuit external to the signal path.

15. The method of claim 11 or 12, further comprising:

receiving a slope control word in the slope control circuit.

16. A method of compensating for temperature in a signal path of an antenna array, the method comprising:

providing a local temperature signal and a remote temperature signal to a slope control circuit in the signal path, the signal path including an antenna element, a first phase shifter or time delay unit, and a first variable gain power amplifier, the local temperature signal indicative of a local temperature in the signal path, and the remote temperature signal indicative of a remote temperature outside the signal path; and

providing a phase control signal to a second phase shifter or a second time delay unit in the signal path using the slope control circuit at least partially in response to both the local temperature signal and the remote temperature signal.

17. The method of claim 16, further comprising providing a gain control signal to a second variable gain amplifier in the signal path using the slope control circuit at least partially in response to the local temperature signal, the remote temperature signal, and at least one of the local temperature signal and the remote temperature signal.

18. The method of claim 17, wherein the slope control circuit is an analog processor that provides the gain control signal to flatten the signal path gain with temperature.

19. The method of claim 17 or 18, wherein the gain control signal is provided at least partially in response to the remote temperature signal.

20. The method of claim 17 or 18, wherein the local temperature signal is provided to the slope control circuit, wherein the gain control signal is provided at least partially in response to the local temperature signal.