Frequency agile transmitter and receiver

Abstract

To provide frequency agile transmitter and receiver.SOLUTION: A frequency-agile transmitter for transmitting either low or high frequency signals is disclosed. The transmitter includes a low-frequency mixing stage for combining at least two input signals encoding input data, the at least two input signals further combined with a local oscillator signal when transmitting a low-frequency signal. The transmitter also includes a transmit element for receiving output from the low-frequency mixing stage. The transmit element includes a signal controller for selectively transmitting the output from the low-frequency mixing stage to one of a low-frequency transmit path for transmitting the low-frequency signal and a high-frequency mixing stage, the high-frequency mixing stage upconverting the output from the low-frequency mixing stage with the local oscillator signal when transmitting a high-frequency signal along the high-frequency transmit path. The transmitting element also includes at least one antenna for outputting one of the low-frequency signal and the high-frequency signal.

Description

[Technical Field]

[0001] Technical Field

[0001] The present invention relates generally to radio frequency transmitters and receivers, and more particularly to transmitters and receivers for multi-band transmission. [Background technology]

[0002] background

[0002] Current communication standards, such as the 5G standard for mobile communications, rely on multiple bands. These bands include low / mid-range frequencies, also known as sub-6 GHz (FR1 band < 6 GHz), and high-range or millimeter-wavelength frequencies (FR2 band > 24-30 GHz, 37-40 GHz, and > 50 GHz). Low-band 5G systems or radios have a longer range than high-band millimeter-wavelength 5G systems, while millimeter-wavelength 5G systems have the advantage of supporting wider bandwidth signals and therefore higher data rates, but at the expense of limited signal range and coverage.

[0003]

[0003] Low-band and high-band 5G systems each have their own advantages and disadvantages. As a result, the two systems are combined within a communication system to allow a choice between bandwidth and range based on the operating environment. For communication systems that rely on multiple frequency bands or equipment incorporating multiple standards using different frequency bands, these typically require multiple systems or radios to enable the communication system to communicate using multiple frequencies. Typically, a dedicated radio is required for each frequency band used.

[0004]

[0004] Communication systems that support multiple frequency bands and communication standards are not uncommon. For example, a mobile handset may have multiple chipsets or modules, each of which supports a particular frequency band or standard. Most of these communication systems rely on being able to switch between these systems or modules as needed to use different frequency bands.

[0005]

[0005] The cost of building such a solution can be quite high as separate chips and modules are required to provide multi-band transmission. Summary of the Invention [Means for solving the problem]

[0006] overview

[0006] This Summary is provided to introduce some concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

[0007]

[0007] One or more embodiments of the present invention include a frequency agile transmitter for transmitting either low or high frequency signals, the transmitter including a low frequency mixing stage for combining at least two input signals that encode input data, the at least two input signals being further combined with a local oscillator signal when transmitting low frequency signals, a transmitting element for receiving output from the low frequency mixing stage, a signal control device for selectively transmitting the output from the low frequency mixing stage to one of a low frequency transmission path for transmitting low frequency signals and a high frequency mixing stage, the high frequency mixing stage upconverting the output from the low frequency mixing stage with the local oscillator signal when transmitting high frequency signals along the high frequency transmission path, and at least one antenna for outputting one of the low frequency signal and the high frequency signal.

[0008] In one embodiment, the signal control device is a radio frequency switch.

[0009]

[0009] In one embodiment, the frequency agile transmitter is a beamforming frequency agile transmitter, which further includes a power divider for generating at least two outputs from the low frequency mixing stage, a plurality of digital phase shifters for adjusting the phase of the at least two outputs, and a plurality of transmit elements, each of the plurality of transmit elements receiving an output from one of the plurality of digital phase shifters.

[0010] In one embodiment, at least one antenna has dual resonance and can transmit high frequency and low frequency signals simultaneously.

[0011] In one embodiment, each of the plurality of transmitting elements has an antenna for a low frequency transmit path and an antenna for a high frequency transmit path.

[0012] In one embodiment, the transmitter further includes a plurality of variable gain amplifiers, each of the plurality of variable gain amplifiers operating on one of the at least two outputs.

[0013]

[0013] In one embodiment, multiple digital phase shifters and multiple variable gain amplifiers enable a narrow beam containing a high frequency signal and a narrow beam containing a low frequency signal to be generated in the far field of each of at least one antenna of the multiple transmitting elements.

[0014] In one embodiment, each of the plurality of variable gain amplifiers and the plurality of digital phase shifters has a different configuration when using the low frequency transmit path compared to the high frequency transmit path.

[0015] In one embodiment, the transmitter further includes a second high frequency transmission path for a second frequency signal output by the at least one antenna.

[0016] In one embodiment, the components of the low frequency mixing stage operate outside the frequency region of interest for the high frequency transmit path.

[0017]

[0017] In one embodiment, the frequency agile transmitter is a mode-selectable frequency-agile transmitter capable of transmitting in a mode selected from a set consisting of a MIMO mode and a beamforming mode, and the mode-selectable frequency-agile transmitter further includes a plurality of lines, a first of the plurality of lines receiving input of at least two input signals and the remaining lines of the plurality of lines being switchable between the at least two input signals and a separate MIMO input signal, a plurality of digital phase shifters for adjusting the phase of each of the lines, and a plurality of transmitting elements, each of the plurality of transmitting elements receiving an output from one of the plurality of digital phase shifters and transmitting a signal from one of the lines.

[0018]

[0018] In one embodiment, each of the MIMO input signals for the remaining lines is received from a corresponding digital-to-analog converter, and each of the digital-to-analog converters is powered off when the mode selectable frequency agile transmitter is operating in beamforming mode.

[0019] In one embodiment, the multiple phase shifters have the same phase shift when the mode selectable frequency agile transmitter is operating in a MIMO mode.

[0020]

[0020] In one embodiment, the frequency-agile transmitter is a mode-selectable frequency-agile transmitter capable of transmitting in a mode selected from a set consisting of a MIMO mode and a beamforming mode, and the mode-selectable frequency-agile transmitter further includes a plurality of lines, each of which has the same phase when in MIMO mode and an independent phase when in beamforming mode.

[0021]

[0021] One or more embodiments of the present invention include a frequency agile receiver for receiving either low or high frequency signals, the receiver including a receiving element including at least one antenna for receiving low frequency signals and high frequency signals, a low frequency receive path for receiving low frequency signals and a signal control device for selectively sending output from the high frequency mixing stage to the low frequency mixing stage, the high frequency mixing stage downconverting the high frequency signal with a local oscillator signal when receiving a high frequency signal from the high frequency receive path, and a low frequency mixing stage for receiving output from the receiving element and separating at least two signals encoding data, the at least two signals being further separated from the local oscillator signal when receiving a low frequency signal.

[0022] In one embodiment, the signal control device is a radio frequency switch.

[0023]

[0023] In one embodiment, the frequency agile receiver is a beamforming frequency agile receiver, which further includes a plurality of receiving elements, each of the plurality of receiving elements receiving at least one of a low frequency signal and a high frequency signal, a plurality of digital phase shifters, each of the phase shifters adjusting the phase of an output from one of the plurality of receiving elements, and a power combiner for combining outputs from the plurality of phase shifters and sending the combined signal to a low frequency mixing stage.

[0024] In one embodiment, at least one antenna has dual resonance and can simultaneously receive high frequency and low frequency signals.

[0025] In one embodiment, each of the plurality of receiving elements has an antenna for a low frequency receiving path and an antenna for a high frequency receiving path.

[0026] In one embodiment, the receiver further includes a plurality of variable gain amplifiers, each of the plurality of variable gain amplifiers operating on an output from one of the plurality of receiving elements.

[0027] In one embodiment, multiple digital phase shifters and multiple variable gain amplifiers allow for receiving narrow beams containing high frequency signals and narrow beams containing low frequency signals.

[0028] In one embodiment, each of the plurality of variable gain amplifiers and the plurality of digital phase shifters has a different configuration when using the low frequency receive path compared to the high frequency receive path.

[0029] In one embodiment, the receiver further includes a second high frequency receive path for a second high frequency signal received by the at least one antenna.

[0030] In one embodiment, the low frequency mixing stage and high frequency mixing stage components provide image rejection for high frequency signals received by the frequency agile receiver.

[0031]

[0031] In one embodiment, the frequency agile receiver is a mode-selectable frequency-agile receiver capable of receiving in a mode selected from a set consisting of a MIMO mode and a beamforming mode, and the mode-selectable frequency-agile receiver further includes a plurality of lines, a first of the plurality of lines outputting at least two signals, and the remaining lines of the plurality of lines being switchable between the at least two signals and a separate MIMO output signal, each line being one of a plurality of receiving elements, each of the plurality of receiving elements receiving at least one of a low frequency signal and a high frequency signal, and one of a plurality of digital phase shifters, the phase shifter adjusting the phase of the output from the receiving element.

[0032]

[0032] In one embodiment, each of the MIMO output signals for the remaining lines is sent to a corresponding analog-to-digital converter, and each of the analog-to-digital converters is powered off when the mode-selectable frequency-agile receiver is operating in beamforming mode.

[0033] In one embodiment, the multiple phase shifters have the same phase shift when the mode selectable frequency agile transmitter is operating in MIMO mode.

[0034]

[0034] In one embodiment, the frequency agile receiver is a mode-selectable frequency-agile receiver capable of receiving in a mode selected from a set consisting of a MIMO mode and a beamforming mode, and the mode-selectable frequency-agile receiver further includes a plurality of lines, each of which has the same phase when in MIMO mode and an independent phase when in beamforming mode.

[0035] Brief description of the diagram At least one embodiment of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: [Brief explanation of the drawings]

[0036] [Figure 1]

[0036] A transmitter system is shown. [Figure 2]

[0037] 1 illustrates a frequency agile transceiver according to one embodiment. [Figure 3]

[0038] 1 illustrates a beamforming frequency agile transceiver according to one embodiment. [Figure 4A]

[0039] 4 illustrates a single-antenna transmitting element and a single-antenna receiving element used in the frequency-agile transceiver of FIG. 2 or FIG. 3. [Figure 4B]

[0039] Figure 2 shows a single-antenna transmitting element and a single-antenna receiving element for use in the frequency-agile transceiver of Figure 2 or Figure 3. [Figure 5]

[0040] 1 illustrates a process for implementing a frequency agile transceiver. [Figure 6]

[0041] 1 illustrates a process for implementing a frequency agile receiver. [Figure 7A]

[0042] 1 shows a transmitter common mixing stage. [Figure 7B]

[0042] Receiver common mixing stage is shown. [Figure 8]

[0043] 1 illustrates a mode selectable frequency agile transmitter according to one embodiment. [Figure 9]

[0044] 1 illustrates a mode selectable frequency agile receiver according to one embodiment. [Figure 10]

[0045] 1 illustrates an alternative mode selectable frequency agile transmitter according to one embodiment. [Figure 11]

[0046] 1 illustrates an alternative mode selectable frequency agile receiver according to one embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0037] Detailed Description

[0047] The following description is given by way of example only and is set forth to provide a more precise understanding of one or more embodiments. In the drawings, like reference numerals are used to identify like parts throughout the figures.

[0038]

[0048] An integrated transceiver system is disclosed that can support multiple frequency bands defined within the same communications standard and multiple bands across multiple standards, thereby making a single chipset more universal in terms of hardware availability. The integrated transceiver system includes both a transmitter and a receiver that can communicate using multiple frequency bands through common hardware components.

[0039]

[0049] A frequency-agile transmitter for transmitting low and high frequency signals is disclosed. The transmitter includes a low-frequency mixing stage for combining at least two input signals encoding input data. The at least two input signals are further combined with a local oscillator signal when transmitting a low-frequency signal. The transmitter also includes a transmitting element for receiving output from the low-frequency mixing stage. The transmitting element also includes a signal controller for transmitting the output from the low-frequency mixing stage along a low-frequency transmission path for transmitting the low-frequency signal, and for transmitting the output from the low-frequency mixing stage to a high-frequency mixing stage for upconverting the output from the low-frequency mixing stage with the local oscillator signal when transmitting a high-frequency signal on the high-frequency transmission path. The transmitting element also includes at least one antenna for outputting one of the low-frequency signal and the high-frequency signal.

[0040]

[0050] Also disclosed is a frequency-agile transmitter for transmitting either low or high frequency signals. The transmitter includes a low-frequency mixing stage for combining at least two input signals that encode the input signals, and the at least two input signals are further combined with a local oscillator signal when transmitting the low-frequency signals. The transmitter also includes a transmitting element for receiving output from the low-frequency mixing stage. The transmitting element includes a signal controller for selectively transmitting the output from the low-frequency mixing stage to one of a low-frequency transmission path for transmitting the low-frequency signals and a high-frequency mixing stage, and the high-frequency mixing stage upconverts the output from the low-frequency mixing stage with the local oscillator signal when transmitting the high-frequency signal along the high-frequency transmission path. The transmitting element also includes at least one antenna for outputting one of the low-frequency signal and the high-frequency signal.

[0041]

[0051] Also disclosed is a frequency-agile receiver for receiving low and high frequency signals. The receiver includes a receiving element including at least one antenna for receiving low frequency signals and high frequency signals. The receiving element also includes a signal controller for sending an output to a low frequency mixing stage, which receives an input from a low frequency receive path for receiving the low frequency signals and an input from a high frequency mixing stage for downconverting the high frequency signals with a local oscillator signal when receiving high frequency signals in the high frequency receive path. The receiver also includes a low frequency mixing stage for receiving the output from the receiving element and for separating at least two signals encoding data, the at least two signals being further separated from the local oscillator signal when receiving the low frequency signals.

[0042]

[0052] Also disclosed is a frequency-agile receiver for receiving either low or high frequency signals, the receiver including a receiving element including at least one antenna for receiving low frequency signals and high frequency signals. The receiving element also includes a signal controller for selectively sending outputs from the low frequency receive path and the high frequency mixing stage to the low frequency mixing stage to receive the low frequency signals, the high frequency mixing stage downconverting the high frequency signals with a local oscillator signal when receiving high frequency signals in the high frequency receive path. The receiver also includes a low frequency mixing stage for receiving the output from the receiving element and separating at least two signals encoding data, the at least two signals being further separated from the local oscillator signal when receiving low frequency signals.

[0043]

[0053] The frequency-agile transceiver architecture provides a method for generating both low / mid-frequency and high-frequency signals by first generating low / mid-frequency signals by frequency up-converting in-phase (I) and quadrature-phase (Q) baseband waveforms with an RF mixer. The low / mid-frequency band signals thus generated from the IQ waveforms can be split into at least two paths: a low / mid-frequency path and a high-frequency path.

[0044]

[0054] In the case of the low / mid frequency path, the signal can be amplified and transmitted via an antenna. In the high frequency path, the low / mid frequency band signal can be frequency upconverted to a high frequency signal, which is further amplified via a power amplifier and transmitted via an antenna. The path selection is performed through an RF switch, which can be controlled to switch between the low / mid frequency path or the high frequency path.

[0045]

[0055] Both low / mid-frequency and high-frequency signals can be generated using a transmit path architecture that utilizes a single conversion mixing stage for the low / mid-frequency signal, along with an array of phase shifters and variable gain amplifiers required for beamforming, amplifiers to boost the signal, and mixing in the high-band path. The first mixing stage is common to both the low / mid-frequency and high-frequency paths and may be referred to as a low / mid-frequency mixing stage or a common mixing stage. The high-frequency path essentially uses the same transmit path as the low / mid-frequency, at least until a second conversion mixing stage or high-frequency mixing stage is required to upconvert the low / mid-frequency signal to a high-frequency band signal.

[0046]

[0056] A similar process occurs in the receive path, where dual conversion stage mixing allows modulation of high frequency signals to baseband I and Q components, and low / mid frequency signals are downconverted only once to obtain baseband I and Q signals. After the receive RF switch, both the low / mid frequency path and the high frequency path share the same circuitry, which includes a common mixing stage.

[0047] Transmitter System

[0057] FIG. 1 illustrates a conventional approach in which multiple chips are used for different standards and / or different frequency bands. The chips are selected one at a time for system operation. A transmitter system 100 transmits signals for each of the standards and / or different frequencies using a single antenna 110. The transmitter system 100 transmits signals from one of three separate transmitters, namely, a GSM cellular transmitter 120, a Bluetooth transmitter 130, and an ultra-wideband transmitter 140, using the single antenna 110. The transmitter system 100 has the advantage of using a single antenna 110 for transmission, but has three separate transmitters. To support additional standards and / or frequency bands, additional transmitters would be added in parallel with the transmitter system 100.

[0048]

[0058] The disclosed frequency agile transceiver system does not require multiple different chipsets to support multiple frequency bands and / or multiple communication standards.

[0049] Frequency Agile Transceiver

[0059] 2 illustrates an exemplary transceiver that supports multiple frequency bands and / or multiple communication standards using frequency-agile transceiver 200. Frequency-agile transceiver 200 is a single-beam transceiver that can transmit and receive at either high, millimeter wavelength or low / mid, sub-6 GHz, radio frequencies. Frequency-agile transceiver 200 is typically used as a component of systems such as cellular or cellular base stations. Frequency-agile transceiver 200 includes a frequency-agile transmitter and a frequency-agile receiver.

[0050]

[0060] There are three main components for frequency-agile transceiver 200. The first is transmit path 246, which operates as a frequency-agile transmitter, transmitting either high or low / mid radio frequencies through a high-frequency transmit path or a low / mid frequency transmit path. The second component is receive path 250, which operates as a frequency-agile receiver, receiving either high or low / mid radio frequencies through a high-frequency receive path or a low / mid frequency receive path. The third component is signal generation chain 248, which is used by both transmit path 246 and / or receive path 250.

[0051] Signal Generation Chain

[0061] The signal generation chain 248 includes a signal combiner 206, which generates a local oscillator signal that pumps or drives the radio frequency mixers of the transmit path 246 or the receive path 250. The local oscillator signal generated by the signal combiner 206 is used to generate a frequency converted signal that can be upconverted for the transmit path 246 or downconverted for the receive path 250. A typical signal source for the signal combiner 206 is a voltage controlled oscillator incorporated as part of a phase locked loop. One output of the signal combiner 206 is sent to a local oscillator amplifier 208, which increases the amplitude or power level of the signal from the signal combiner 206.

[0052]

[0062] The local oscillator frequency multiplier 210 receives the output from the local oscillator amplifier 208 and multiplies the frequency of the output signal by a multiplication factor n, where n can be an integer, such as 1, 2, 3, 4, etc. The local oscillator frequency multiplier 210 may include an integrated amplifier gain block in addition to the local oscillator amplifier 208 to counter any signal loss caused by the frequency multiplication. The local oscillator frequency multiplier 210 is typically used to generate high-frequency local oscillator signals because it can be difficult to generate high-frequency local oscillator signals with sufficient driver power and low phase noise directly in the signal generation circuitry of the signal synthesizer 206. The power distribution network 212 splits the output from the local oscillator frequency multiplier 210 to either the transmit path 246 or the receive path 250. One requirement of the power distribution network 212 is to ensure that the various signal output ports are isolated from each other, thus ensuring that there is no signal leakage or interference between the transmitting and receiving elements of the transmit path 246 and the receive path 250. The power distribution network may be a power divider or may be composed of transmission lines or tracks that can distribute power.

[0053] Transmission Path

[0063] The transmit path 246 has four inputs: an in-phase input 202, a quadrature-phase input 204, an output from a signal combiner 206, and an output from a power distribution network 212. The in-phase input 202 and the quadrature-phase input 204 encode input data for transmission using the frequency-agile transceiver 200 and are received from other components of the device, including the frequency-agile transceiver 200. The combination of the in-phase input 202 and the quadrature-phase input 204 may be referred to as the input transmit signal. The output from the signal combiner 206 is received by a local oscillator transmit (Tx) amplifier 214, which increases the power level of the local oscillator signal delivered to the transmit (Tx) 90° hybrid 219. The local oscillator Tx amplifier 214 increases the level of the local oscillator signal output from the signal combiner 206. The output from the local oscillator Tx amplifier 214 is at a level suitable to pump or drive the power required by the I-phase transmit (Tx) radio frequency mixer 216 and the Q-phase transmit (Tx) radio frequency mixer 218 to create the frequency mixing products at the outputs of the I-phase Tx radio frequency mixer 216 and the Q-phase Tx radio frequency mixer 218.

[0054]

[0064] The output from the local oscillator Tx amplifier 214 is received by a transmit (Tx) 90° hybrid 219, which splits the local oscillator pump into two signals with the same power level but a 90° phase difference. One output from the Tx 90° hybrid 219 has a 90° phase change and is input to the I-phase Tx radio frequency mixer 216, while the output signal with a 180° phase change is sent to the Q-phase Tx radio frequency mixer 218.

[0055]

[0065] The I-phase Tx radio frequency mixer 216 and the Q-phase Tx radio frequency mixer 218 use transistor, diode-based nonlinear switching elements, or other types of nonlinear elements to mix the in-phase input 202 or the quadrature-phase input 204, respectively, with a local oscillator pump frequency from a Tx 90° hybrid 219. The output from the I-phase Tx radio frequency mixer 216 is an upconverted RF signal at a frequency that is the sum and difference of the in-phase input 202 and the local oscillator pump signal from the Tx 90° hybrid 219. The output from the Tx 90° hybrid 219 is an upconverted RF signal at a frequency that is the sum and difference of the quadrature-phase input 204 and the local oscillator pump signal from the Tx 90° hybrid 219. In addition, various undesirable sums and differences of harmonics of the in-phase input 202 for the I-phase Tx radio frequency mixer 216 or the quadrature-phase input 204 for the Tx 90° hybrid 219 and the local oscillator pump signal from the Tx 90° hybrid 219 may also be generated.

[0056]

[0066] The transmit (Tx) input signal summing circuit 220 rejects either the sum or difference of the frequencies from the I-phase Tx radio frequency mixer 216 and the Q-phase Tx radio frequency mixer 218. The signal summing circuit may be implemented as an in-phase power combiner or a quadrature-phase power combiner or even a balun. The output from the Tx input signal summing circuit 220 is sent to a transmit (Tx) low / mid frequency intermediate frequency (IF) amplifier 222, which boosts the upconverted RF signal. The output from the Tx low / mid frequency IF amplifier 222 may be referred to as the processed transmit signal.

[0057]

[0067] The output from the Tx low / mid frequency IF (intermediate frequency) amplifier 222 is sent to the transmit element 230, which has an antenna for each of the low / mid frequency transmit path and the high frequency transmit path and receives the output from the low / mid frequency mixing stage. The other input received by the transmit element 230 is the output from the power distribution network 212, which is the high frequency local oscillator signal mentioned above. The transmit element 230 also has a transmit (Tx) RF switch 232, which is a single-pole, double-throw switch that selects which output to transmit the processed transmit signal for either the high frequency transmit path or the low / mid frequency transmit path. The Tx RF switch 232 enables signal transmission in either the low / mid frequency band or the high frequency band. The Tx RF switch 232 allows the single transmitter architecture to be used for either low / mid frequency transmission, which has a longer link range but a lower data rate than high frequency transmission, or high frequency transmission, which has a higher data rate but a shorter link range than low / mid frequency transmission. The Tx RF switch 232 can send the output from the low / mid frequency mixing stage along a low frequency transmit path for transmitting low frequency signals, and send the output from the low frequency mixing stage to a high frequency mixing stage for upconverting the output from the low frequency mixing stage with a local oscillator signal when transmitting high frequency signals on the high frequency transmit path.

[0058]

[0068] When the low / mid frequency transmit path is selected, the processed transmit signal is input to a transmit (Tx) low / mid frequency RF power amplifier chain 234. The Tx low / mid frequency RF PA chain 234 receives the processed transmit signal as a radio frequency signal, amplifies the signal to increase its power level, and then transmits the amplified signal to a low / mid frequency transmit (Tx) antenna 236. The Tx low / mid frequency RF PA chain 234 may have multiple amplifier stages and may use a power amplifier architecture to increase average or back-off efficiency. In other words, the power amplifier architecture may use a Doherty architecture or an architecture based on envelope tracking.

[0059]

[0069] When the Tx RF switch 232 selects the high-frequency transmit path, the processed transmit signal from the Tx low / mid frequency IF amplifier 222 is sent to the up-conversion mixer 238. In the up-conversion mixer 238, the processed transmit signal, which is a wideband intermediate frequency low / mid frequency signal, is up-converted to a high-frequency signal. The up-conversion mixer 238 is a second-stage dual-conversion mixer in the transmit path 246, and the first-stage dual-conversion mixer is IQ mixing performed by the I-phase Tx radio frequency mixer 216, the Q-phase Tx radio frequency mixer 218, and the Tx input signal summing circuit 220. The up-conversion mixer 238 also receives input from the power distribution network 212 and performs similar functions to the I-phase Tx radio frequency mixer 216 and the Q-phase Tx radio frequency mixer 218.

[0060]

[0070] The output from the upconversion mixer 238 is sent to a transmit (Tx) high-frequency PA chain 240, which amplifies the signal output from the upconversion mixer 238 to generate sufficient power to meet the power budget demands for the high-frequency transmit path. The Tx high-frequency PA chain 240 is connected to a high-frequency transmit (Tx) antenna 242 to transmit the high-frequency signal from the frequency-agile transceiver 200.

[0061] Receiving Route

[0071] The receive path 250 of the frequency-agile transceiver 200 begins by receiving a transmission via the high-frequency receive path using a high-frequency receive (Rx) antenna 292 or via the low / mid-frequency receive path using a low / mid-frequency receive (Rx) antenna 286. The high-frequency Rx antenna 292 and the low / mid-frequency Rx antenna 286 both form part of the receive element 280, which receives input from both their respective antennas and, if the high-frequency receive path is used, from the power distribution network 212 of the signal generation chain 248. The receive element has an antenna for each of the low / mid-frequency receive path and the high-frequency receive path. In the low / mid-frequency receive path, the low / mid-frequency Rx antenna 286 transmits the received signal to a receive (Rx) low / mid-frequency low-noise amplifier (LNA) chain 284. The Rx low / mid frequency LNA chain 284 amplifies low / mid frequency signals, such as sub-6 GHz low / mid band 5G signals, without significantly degrading the signal-to-noise ratio.

[0062]

[0072] The Rx low / mid frequency LNA chain 284 is connected to a receive (Rx) radio frequency (RF) switch 282. The Rx RF switch 282 is similar to the previously described Tx RF switch 232 in that the Rx RF switch 282 is a single-pole, double-throw switch that selects between the high frequency receive path and the low / mid frequency receive path. The Tx RF switch 232 sends its output to a low frequency mixing stage and receives an input from either the low frequency receive path for receiving a low frequency signal, or from a high frequency mixing stage for downconverting the high frequency signal with a local oscillator signal when receiving a high frequency signal in the high frequency receive path.

[0063]

[0073] The high-frequency receive path signal is received by a high-frequency Rx antenna 292 and sent to a high-frequency low-noise amplifier (LNA) chain 290, which amplifies the received high-frequency signal, such as a wideband mm-wave 5G signal, without adding a significant amount of noise. While all amplifiers add some noise to the received signal, the high-frequency LNA chain 290 amplifies the received signal without significantly degrading the signal-to-noise ratio. The output from the high-frequency LNA chain 290 is sent to a down-conversion mixer 288. The down-conversion mixer 288 is the first step in a dual-conversion mixing process to down-convert the frequency of the high-frequency receive path from the high-frequency Rx antenna 292 and modulate the received high-frequency signal to recover and output the data. Subsequent stages of the dual-conversion mixing process are described below. The output from downconversion mixer 288 is sent to Rx RF switch 282, which receives the downconverted signal from downconversion mixer 288 and passes the signal to receive (Rx) low / mid frequency IF amplifier 272. When receive element 280 is operating in the low / mid frequency receive path, Rx RF switch 282 sends the output from Rx low / mid frequency LNA chain 284 to Rx low / mid frequency IF amplifier 272. Rx RF switch 282 selects between the low / mid frequency receive path and the high frequency receive path for modulation by downstream circuitry and subsequent data recovery and output. Rx low / mid frequency IF amplifier 272 boosts the downconverted signal from the high frequency receive path or the signal from the low / mid frequency receive path.

[0064]

[0074] The output from the Rx low / mid frequency IF amplifier 272 is sent to the receive (Rx) input signal splitter circuit 270, where the received signal is split between the I-phase receive (Rx) radio frequency mixer 266 and the Q-phase receive (Rx) radio frequency mixer 268. The I-phase Rx radio frequency mixer 266 and the Q-phase Rx radio frequency mixer 268 are used when the receive path 250 uses either the low / mid frequency receive path operating on low / mid frequency signals or the high frequency receive path operating on high frequency signals to remove the carrier in the signal and modulate the signal received through either the low / mid frequency path operating on low / mid frequency signals or the high frequency receive path operating on high frequency signals. The carrier signal is removed using the output from the signal combiner 206 received by the local oscillator receive (Rx) amplifier 264. The local oscillator Rx amplifier 264 operates similarly to the local oscillator Tx amplifier 214 already described with respect to the transmit path 246. The output from the local oscillator Rx amplifier 264 is sent to a receive (Rx) 90° hybrid 269, which operates similarly to the Tx 90° hybrid 219 of the transmit path 246. The 0° output from the Rx quadrature hybrid 269 is received by an I-phase Rx radio frequency mixer 266, and the 90° output from the Rx 90° hybrid 269 is received by a Q-phase Rx radio frequency mixer 268. The output from the Rx 90° hybrid 269 is used to remove the carrier frequency from the received signal. The outputs from the receive path 250 are an in-phase output 252 and a quadrature-phase output 254, each of which is an I- and Q-phase signal of the output data from the receive path 250.

[0065]

[0075] The Rx input signal splitter circuit 270, the I-phase Rx radio frequency mixer 266, the Q-phase Rx line frequency mixer 268 and the local oscillator Rx amplifier 264 are all part of the second stage of the dual conversion mixing process and form a receive IQ splitter.

[0066] Signal Generation Chain Operation

[0076] One feature of frequency-agile transceiver 200 is that, as mentioned above, only one output of signal generation chain 248 is selectively used by transmit path 246 or receive path 250. When transmit path 246 is transmitting using the low / mid frequency transmit path, the low / mid frequency output of signal generation chain 248 is used as the input to local oscillator Tx amplifier 214. Signal generation chain 248 does not output from power distribution network 212 to upconversion mixer 238. When the high frequency transmit path is used by transmit path 246, the low / mid frequency output from signal generation chain 248 to local oscillator Tx amplifier 214 is disabled and the high frequency output from power distribution network 212 to upconversion mixer 238 is enabled. The same is true for receive path 250. If the received signal uses the low / mid frequency receive path, the low / mid frequency output from the signal generation chain 248 to the local oscillator Rx amplifier 264 is used and the high frequency output from the power distribution network 212 is disabled. If the millimeter wavelength receive path is used, the high band output from the power distribution network 212 is used and the low / mid band output from the signal generation chain 248 to the local oscillator Rx amplifier 264 is disabled.

[0067] Beamforming Frequency Agile Transceiver

[0077] 3 illustrates a beamforming frequency agile transceiver 300 similar to frequency agile transceiver 200 described above with respect to FIG. 2, but modified to provide beamforming frequency agility for transmit path 346 and receive path 350. Beamforming frequency agile transceiver 300 may operate in one of two operating frequency bands for transmit path 346, e.g., low / mid or high frequencies, or one of two operating frequency bands for receive path 350, e.g., low / mid or high frequencies. Transmit path 346 and receive path 350 may operate independently at different frequencies. That is, similar to frequency agile transceiver 200, the operating frequency band of transmit path 346 need not be the same as the operating frequency band of receive path 350 when the two are simultaneously in operation.

[0068]

[0078] The beamforming frequency agile transceiver 300 is shown to have four transmit antennas and four receive antennas. Many aspects of the beamforming frequency agile transceiver 300 are common to the frequency agile transceiver 200, and common components share common reference numbers.

[0069]

[0079] Beamforming involves multiple transmit or receive elements, each excited by a signal of slightly different phase. Because each transmit element is an antenna for each of the low / mid-frequency and high-frequency transmit paths, the signal from each transmit element is transmitted via a corresponding antenna. As a result, the signals from the multiple transmit sections, all with unique phases, interfere constructively at a point in space, creating a narrow radio beam or signal. In all other directions, the signal waveforms traveling from the antennas combine destructively, resulting in a signal null. A similar mechanism occurs at the receiver when receiving a signal.

[0070]

[0080] The advantage of beamforming is that signals can propagate farther than would be possible if they were transmitted isotropically in space, i.e., the signals are transmitted simultaneously in all directions. With isotropic transmission, only a small portion of the signal is received at a point by a user terminal, resulting in an attenuated signal. In other words, the range of the wireless link is substantially reduced using isotropic transmission compared to the range for beamforming transmission.

[0071]

[0081] As previously mentioned, radios that operate based on beamforming require multiple transmit and receive elements, with adjacent transmit and receive sections sharing a single antenna. For example, a radio system supporting multiple frequency bands, such as the sub-6 GHz 5G band around 3.5 GHz, often referred to as mid-band 5G, and the mmWave 5G band around 28 GHz, often referred to as high-band, requires two separate radio systems, or 2n transmit and receive elements, one for each frequency band, where "n" is the number of transmit or receive elements required to generate the beamforming. By halving the number of transmit or receive elements, the cost and space occupied by the beamforming elements can be reduced while still supporting multiple frequency bands. This can be advantageous in systems such as mobile phones, where space is at a premium and separate chipsets or beamforming integrated circuits are required for multiple frequency bands.

[0072] Signal generation pathway

[0082] Signal generation chain 348 operates similarly to signal generation chain 248 described above in that signal generation chain 348 includes signal combiner 206, local oscillator amplifier 208, and local oscillator frequency multiplier 210. The output from local oscillator frequency multiplier 210 is passed to power distribution network 312. Power distribution network 312 differs from power distribution network 212 in that there are four outputs for transmit path 346 and four outputs for receive path 350. Power distribution network 312 operates best when the various signal output ports are isolated from each other so there is no signal crossover or interference between the transmitting elements of transmit path 346, the receiving elements of receive path 350, or the transmitting and receiving elements of transmit path 346 and receive path 350. The power distribution network may be a power divider or may be comprised of transmission lines or tracks that can distribute power.

[0073] Transmission Path

[0083] The transmit path 346 receives the in-phase input 202 and the quadrature-phase input 204, as previously described for the frequency-agile transceiver 200. However, the transmit path 346 differs after the output from the Tx low / mid frequency IF amplifier 222. Rather than proceeding from the Tx low / mid frequency IF amplifier 222 to the transmit element 230, the output from the Tx low / mid frequency IF amplifier 222 proceeds to a transmit (Tx) power divider network 324 in the beamforming frequency-agile transceiver 300. The Tx power divider network 324 splits the input from the Tx low / mid frequency IF amplifier 222 into four paths, also referred to as beamforming paths. The Tx power divider network 324 is the beginning of the beamforming signal generator that provides input to the transmit element and generates four outputs for the beamforming frequency-agile transceiver 300. In other embodiments, the Tx power divider network may generate more than one output, i.e., one output for each beamforming path. Each output generates a phase- and amplitude-level-shifted signal for the transmit element. Each output or line of the Tx power divider network 324 is connected to one of four transmit digital phase shifters: transmit (Tx) digital phase shifter 1 326a, transmit (Tx) digital phase shifter 2 326b, transmit (Tx) digital phase shifter 3 326c, and transmit (Tx) digital phase shifter 4 326d. Each transmit phase shifter may be an n-bit digital phase shifter programmed by a control signal (not shown) to impart a phase shift to the received signal. The resolution of each transmit phase shifter determines the smallest phase change achievable within the allowed phase range. Each phase shifter is used by the beamforming frequency-agile transceiver 300 to modulate the phase of the transmitted signal to provide the phase-shift component of the beamforming capability.

[0074]

[0084] The output of each path from one of the transmit digital phase shifters is sent to one of four transmit variable gain amplifiers: transmit (Tx) variable gain amplifier 1 328a, transmit (Tx) variable gain amplifier 2 328b, transmit (Tx) variable gain amplifier 3 328c, or transmit (Tx) variable gain amplifier 4 328d. The transmit variable gain amplifiers are used to vary the amplitude of each of the four paths in the transmit path 246 because beamforming arrays require a set of signals that each have, or at least can have, adjustments to amplitude and phase to create focused beams in the far field. Each transmit variable gain amplifier modulates the phase to create amplitude variations for each path's signal, which is used to generate a narrow or focused beam. In a typical case, a frequency-agile transceiver has multiple variable gain amplifiers, each operating on one of the outputs from the Tx power divider network.

[0075]

[0085] The phase shifters and transmit variable gain amplifiers are configured using control signals, not shown. The configuration of the phase shifters and transmit variable gain amplifiers differs depending on whether the beamforming frequency-agile transceiver 300 is configured to operate for the high-frequency transmit path or the low / mid-frequency transmit path due to differences in how different frequency bands are handled. That is, the phase shifters and transmit variable gain amplifiers may have different configurations when using the low-frequency transmit path compared to the high-frequency transmit path, including the gain for the transmit variable gain amplifier and the phase for the phase shifters.

[0076]

[0086] One feature of the Tx power divider network 324 is that it provides isolation between the output ports of each path or line, reducing or minimizing interference between each of the four paths. Any form of interference or crosstalk is detrimental to the correct operation of the beamforming frequency-agile transceiver 300 and can prevent the transmit elements from forming the focused or directional beams necessary for accurate beamforming operation. It is also important that the Tx power divider network 324 does not introduce phase or amplitude distortion between the input from the Tx low / mid frequency IF amplifier 222 and the outputs to the transmit digital phase shifters. Ideally, the input from the Tx low / mid frequency IF amplifier 222 and the outputs to the transmit digital phase shifters have equal phase and amplitude, but maintaining phase and amplitude balance within specific limits also allows the transmit path 346 to operate correctly. Limited distortion between the input from the Tx low / mid frequency IF amplifier 222 and the outputs to the transmit digital phase shifters can reduce or minimize additional phase and amplitude calibration for the transmit phase shifters and transmit variable gain amplifiers, respectively.

[0077]

[0087] The beamforming frequency-agile transceiver 300 has four transmit elements: transmit element 1 330a, transmit element 2 330b, transmit element 3 330c, and transmit element 4 330d. Each of the transmit elements operates in a manner similar to that described for transmit element 230 of frequency-agile transceiver 200. Each of the transmit elements operates on one of the paths, also referred to as line or beamforming paths, from the Tx power divider network 324. For transmit element 1 330a, the input has a phase set by Tx digital phase shifter 1 326a and an amplitude set by Tx variable gain amplifier 1 328a. Each of the transmit elements also receives one of the outputs from the power distribution network 312. Each of the transmit elements has a low / mid frequency transmit (Tx) antenna 236 and a high frequency transmit (Tx) antenna 242. The high-frequency Tx antenna 242 is a wide-bandwidth transmit antenna capable of beamforming to generate a focused, narrow beam directed toward the user terminal. Some requirements for the high-frequency Tx antenna 242 may include high gain, good input return loss, minimal power in side lobes, and compact size. For the low / mid-frequency Tx antenna 236 of the transmit element of the beamforming frequency agile transceiver 300, the low- or mid-band transmit antenna transmits signals of respective phases that result in a focused beam in the far field. The requirements for the low / mid-frequency Tx antenna 236 of the beamforming frequency agile transceiver 300 may be the same as the low / mid-frequency Tx antenna 236 of the frequency agile transceiver 200, and may be co-located with the high-frequency antenna without interference.

[0078]

[0088] Each path or line is connected to a digital phase shifter, a variable gain amplifier and a transmit element, for example, line 1 has Tx digital phase shifter 1 326a, Tx variable gain amplifier 1 328a and transmit element 1 330a, and similarly for lines 2, 3 and 4.

[0079]

[0089] The transmit path described above, comprising multiple digital phase shifters, such as Tx Digital Phase Shifter 1 326a, and multiple variable gain amplifiers, such as Tx Variable Gain Amplifier 1 328a, enables the generation of narrow beams containing high frequency signals and narrow beams containing low frequency signals in the far field of each of at least one antenna of the multiple transmit elements.

[0080] Receiving Route

[0090] Receive path 350 receives signals at each of four receive elements: receive element 1 380a, receive element 2 380b, receive element 3 380c, and receive element 4 380d. Each receive element operates in the same or similar manner as receive element 280 described above with respect to frequency-agile transceiver 200. Each receive element has an antenna for each of its low / mid frequency receive path and high frequency receive path. Each receive element receives an input from power distribution network 312, which is used within the associated receive element by downconversion mixer 288 to remove the carrier received on the receive element's high frequency receive path. Each receive element is connected to a separate path or line, and the amplitude and phase are adjusted within the beamforming signal combiner that receives the receive element's input and provides the output of Rx low / mid frequency IF amplifier 272.

[0081]

[0091] Amplitude adjustment for each path is performed by one of four receive variable gain amplifiers: receive (Rx) variable gain amplifier 1 378a, receive (Rx) variable gain amplifier 2 378b, receive (Rx) variable gain amplifier 3 378c, and receive (Rx) variable gain amplifier 4 378d. Each of the receive variable gain amplifiers is similar to the transmit variable gain amplifier in transmit path 346, except that the orientation of the receive variable gain amplifier is reversed to receive as input a signal from one of the receive elements. The receive variable gain amplifiers may differ from the transmit variable gain amplifiers in some of their operating parameters, such as output power capacity and other performance criteria.

[0082]

[0092] Phase adjustment for each path is performed by one of four receive digital phase shifters: receive (Rx) digital phase shifter 1 376a, receive (Rx) digital phase shifter 2 376b, receive (Rx) digital phase shifter 3 376c, and receive (Rx) digital phase shifter 4 376d. The receive digital phase shifters are responsible for shifting the signal phase for each path by a specific angle. Each receive phase shifter shifts the phase of the received signal for that path by the specific angle necessary to enable constructive addition of the signals for each path in receive path 350. The constructive addition is performed in the Rx power combiner network 374. The Rx power combiner network 374 is similar to the Tx power divider network 324, but combines the signals in each of the four paths from each corresponding receive element via a receive variable gain amplifier and a receive digital phase shifter. The Rx power combiner network 374 should have low loss and isolation between the input ports for each path and between the input of each path and the output from the Rx power combiner network 374 .

[0083]

[0093] Similar to the transmit path 346, each path or line in the receive path 350 is connected to a receive element, a variable gain amplifier, and a digital phase shifter; for example, line 1 has receive element 1 380a, Rx variable gain amplifier 1 378a, and Rx digital phase shifter 1 376a. Similarly for lines 2, 3, and 4. In the general case, a frequency-agile transceiver will have multiple variable gain amplifiers, each operating on one of the outputs from the receive elements.

[0084]

[0094] The phase shifter and receive variable gain amplifier are configured using control signals, not shown. The configuration of the phase shifter and receive variable gain amplifier differs depending on whether the beamforming frequency-agile transceiver 300 is configured to operate for the high-frequency receive path or the low / mid-frequency receive path due to differences in how different frequency bands are processed. That is, the phase shifter and receive variable gain amplifier may have a different configuration when using the low-frequency receive path compared to the high-frequency receive path, including the gain for the receive variable gain amplifier and the phase for the phase shifter. When the low / mid-frequency receive path and the high-frequency receive path operate simultaneously, the phase shifter and receive variable gain amplifier may be configured with values ​​that allow both to operate simultaneously.

[0085]

[0095] The Rx power combiner network 374 sends the combined signal to the Rx low / mid frequency IF amplifier 272 , with the remainder of the receive path 350 operating as previously described with respect to the frequency-agile transceiver 200 .

[0086] The above-described receive path, which includes multiple digital phase shifters, e.g., Rx variable gain amplifier 1 378a, and multiple variable gain amplifiers, e.g., receive element 1 380a, allows for receiving a narrow beam containing high-frequency signals and a narrow beam containing low-frequency signals.

[0087] Single Antenna Element

[0096] 4A illustrates a single-antenna transmit element 400 that differs from transmit element 230 and the transmit element of beamforming frequency agile transceiver 300 described above. Some of the components of single-antenna transmit element 400 are the same as those used in transmit element 230 or the transmit element of beamforming frequency agile transceiver 300. Single-antenna transmit element 400 receives as input a signal input 430, such as an input from Tx low / mid frequency IF amplifier 222 of FIG. 2 or an input from one of the transmit variable gain amplifiers of beamforming frequency agile transceiver 300. Single-antenna transmit element 400 also receives a power distribution network input 428, such as from power distribution network 212 or power distribution network 312. Signal input 430 and power distribution network input 428 are processed as part of the high-frequency transmit path already described for upconversion mixer 238 and Tx high-frequency PA chain 240. The output from the upconversion mixer 238 is sent to a transmit (Tx) antenna output switch 436, which is a single-pole, double-throw (SPDT) RF switch that selects input from either the low / mid frequency transmit path or the high frequency transmit path and sends the output to a dual-band transmit (TX) antenna 442. In the low / mid frequency transmit path, the signal input 430 is sent to the Tx antenna output switch 436 via the Tx RF switch 232 and the Tx low / mid frequency RF PA chain 234. The single dual-band Tx antenna 442 simultaneously supports low / mid frequencies, such as sub-6 GHz frequency bands, and high frequency bands, such as mm-wave 5G bands.

[0088]

[0097] 4B illustrates a single-antenna receive element 410 that differs from receive element 280 and the receive element of beamforming frequency agile transceiver 300 described above. The primary modification, compared to the dual-antenna design of receive element 280 and the receive element of beamforming frequency agile transceiver 300, is that single-antenna receive element 410 has a single antenna for a low / mid frequency receive path and a high frequency receive path. Single-antenna receive element 410 outputs a signal output 480 to Rx low / mid frequency IF amplifier 272 of frequency agile transceiver 200 or to one of the receive variable gain amplifiers of beamforming frequency agile transceiver 300, such as Rx variable gain amplifier 1 378a. Single-antenna receive element 410 has a single dual-band receive (Rx) antenna 492 capable of receiving low / mid frequencies, such as sub-6 GHz 5G, or high frequencies, such as mmWave 5G. The high-frequency receive path or the low / mid-frequency receive path is selected by a receive (Rx) antenna input switch 486, which is a single-pole, double-throw RF switch. When the Rx antenna input switch 486 selects the low / mid-frequency receive path, the signal travels from the dual-band Rx antenna 492 through the Rx antenna input switch 486 to the Rx RF switch 282 to the Rx low / mid-frequency LNA chain 284, and then output as signal output 480. When the Rx antenna input switch 486 selects the high-frequency transmit path, the signal is received by the dual-band Rx antenna 492 and sent via the Rx antenna input switch 486 to the high-frequency LNA chain 290 and downconversion mixer 288, where the carrier frequency is removed using a power distribution network input 478. The power distribution network input 478 is an output from the power distribution network 212 or the power distribution network 312. Once the carrier is removed at the power distribution network input 478, the signal passes through the Rx RF switch 282 and is output as signal output 480.

[0089]

[0098] The single-antenna transmit element 400 and the single-antenna receive element 410 may be used in place of the transmit and receive elements of frequency-agile transceiver 200 or the transmit and receive elements of beamforming frequency-agile transceiver 300. In one embodiment, the single-antenna transmit element 400 has dual resonance and may simultaneously transmit high-frequency and low-frequency signals. Similarly, the single-antenna receive element 410 has dual resonance and may simultaneously receive high-frequency and low / mid-frequency signals.

[0090] Frequency Agile Transceiver Process

[0099] The processes for a frequency agile transmitter and a frequency agile receiver will now be described with reference to Figures 5 and 6. First, the frequency agile transmitter process 500 will be described with reference to Figure 5. The frequency agile transmitter process 500 may be implemented as the transmitter component of a frequency agile transmitter, such as frequency agile transceiver 200 or beamforming frequency agile transceiver 300. The frequency agile transmitter process 500 begins with frequency selection 505, where a high frequency or low / mid frequency path is selected. Frequency selection can occur later, but must be before any of the frequency check steps described below.

[0091]

[0100] In IQ signal receive 510, I and Q phases, e.g., in-phase input 202 and quadrature-phase input 204, are received. The IQ signals are in-phase and phase-shifted copies of the received data, which are transmitted by frequency agile transmitter process 500. In add low / mid frequency carrier 530, frequency agile transmitter process 500 adds a low / mid frequency carrier, where a carrier signal, such as the output from signal combiner 206, is added to the I and Q phases in I-phase Tx radio frequency mixer 216 and Q-phase Tx radio frequency mixer 218. As described above, Tx 90° hybrid 219 applies a phase shift to the output of signal combiner 206 before combining it with the Q phase. Next, in signal processing 540, the I and Q phases are combined and amplified as described with respect to Tx input signal summing circuit 220 and Tx low / mid frequency IF amplifier 222 of frequency agile transceiver 200 and beamforming frequency agile transceiver 300.

[0092]

[0101] In the beamforming frequency-agile transceiver 300, the combined I and Q phase signals from signal processing 540 are split and amplified in beamforming processing 550. Beamforming processing 550 is an optional step used for the beamforming frequency-agile transmitter and is performed by the Tx power divider network 324, a Tx digital phase shifter, e.g., Tx digital phase shifter 1 326a, and a Tx variable gain amplifier, e.g., Tx variable gain amplifier 1 328a. In transmit path selection 560, an RF switch within the transmit element, e.g., Tx RF switch 232, selects either the low / mid frequency or high frequency transmit path based on the selection made in frequency selection 505. If the high frequency transmit path is selected, high frequency check 570 is yes, and the process proceeds to high frequency carrier addition 580, where a high frequency carrier signal from the power distribution network 312 or power distribution network 212 is combined using the upconversion mixer 238. The signal is then processed by transmit signal 590, which amplifies and transmits the signal to the antenna. If high frequency check 570 is no, frequency agile transmitter process 500 proceeds to transmit signal 590.

[0093]

[0102] The frequency agile receiver process 600 will now be described with reference to FIG. 6. The frequency agile receiver process 600 may be implemented using a frequency agile receiver, such as the transmitter component of the frequency agile transceiver 200 or the beamforming frequency agile transceiver 300. The frequency agile receiver process 600 begins with signal reception 605, where an antenna receives a transmitted signal. The received signal is amplified by the Rx low / mid frequency LNA chain 284 or the high frequency LNA chain 290 in signal amplification 610. In frequency selection 615, the high frequency path or the low / mid frequency path for the frequency agile receiver is selected. In high frequency check 620, a check is performed to see if the frequency agile receiver is operating with a high frequency signal. If the frequency agile receiver is operating with a high frequency signal, frequency agile receiver process 600 proceeds to high frequency carrier signal removal 625, where the high frequency carrier signal received from the power distribution network, e.g., power distribution network 212 or power distribution network 312, is removed in downconversion mixer 288. If high frequency check 620 determines that the low / mid frequency receive path is selected, frequency agile receiver process 600 proceeds to receive path selection 630.

[0094]

[0103] The receive path selection 630 operates an RF switch, such as the Rx RF switch 282, to select either the high-frequency receive path or the low / mid-frequency receive path. If beamforming is used, the amplified signal from the antenna in the case of a low / mid-frequency signal or the demodulated high-frequency signal is amplified and phase-shifted in the beamforming process 635. The amplification, shifting, and combining are performed by a variable gain amplifier, e.g., Rx variable gain amplifier 1 378a, a digital phase shifter, e.g., Rx digital phase shifter 1 376a, and a power combiner network, e.g., Rx power combiner network 374. The beamforming process 635 is an optional step used for beamforming in a frequency-agile receiver, in which each of the receive signals is phase-adjusted before being combined.

[0095]

[0104] In signal amplification 640, the signal, which is the combined signal for a beamforming frequency agile receiver or the amplified signal from signal amplification 610 in the case of a non-beamforming frequency agile receiver, is amplified by an amplifier, for example, Rx low / mid frequency IF amplifier 272.

[0096]

[0105] In I and Q signal split 645, output data in the form of I and Q signals is separated, as described for Rx input signal split circuit 270. Next, the carrier signal is removed from the I and Q signals in low / mid frequency carrier signal removal 655. Carrier signal removal is performed as described for Rx 90° hybrid 269, I-phase Rx radio frequency mixer 266, and Q-phase Rx radio frequency mixer 268. After low / mid frequency carrier signal removal 655, frequency agile receiver process 600 proceeds to output the data as I and Q signals at IQ signal output 660, as previously described for in-phase output 252 and quadrature-phase output 254.

[0097] Characteristics of frequency agile transmission and reception

[0106] The frequency-agile transceiver uses two data mixing stages: a first data mixing stage, also called a low / mid frequency mixing stage, or a common mixing stage, which is an I-phase Tx radio frequency mixer 216, a Q-phase Tx radio frequency mixer 218, and a Tx input signal summing circuit 220 for the transmit path; and an I-phase Rx radio frequency mixer 266, a Q-phase Rx radio frequency mixer 268, and an Rx input signal splitting circuit 270 for the receive path. In the case of a frequency-agile transmitter, the low / mid frequency mixing stage combines at least two input signals, e.g., an in-phase input 202 and a quadrature-phase input 204, that encode input data, and the at least two input signals are further combined with a local oscillator signal, e.g., the output from a Tx 90° hybrid 219, when transmitting low-frequency signals. In the case of a frequency-agile receiver, the low / mid frequency mixing stage receives the output from a receiving element, e.g., receive element 280 or receive element 1 380a, and separates at least two signals that encode data, e.g., in-phase output 252 and quadrature-phase output 254. The at least two signals are further separated from a local oscillator signal, e.g., the output from Rx 90° hybrid 269, when receiving low frequency signals.

[0098]

[0107] 7A and 7B illustrate common mixing stages, with FIG. 7A showing a transmitter common mixing stage 700 and FIG. 7B showing a receiver common mixing stage 750. The transmitter common mixing stage 700 also includes the Tx low / mid IF amplifier 222, while the receiver common mixing stage 750 includes the Rx low / mid IF amplifier 272.

[0099]

[0108] The second data mixing stage, also referred to as the high-frequency mixing stage, is the up-conversion mixer 238 for the transmit path and the down-conversion mixer 288 for the receive path. The two-stage mixing ensures that the image frequencies resulting from the mixing process are far removed from the up- or down-converted frequencies of interest, eliminating the need for explicit filters or filtering. In the receive path of the frequency-agile transceiver 200 or the beamforming frequency-agile transceiver 300, the low-frequency mixing stage and high-frequency mixing stage components provide image rejection of the high-frequency signals received by the frequency-agile receiver. Note that if a common mixing stage is used for high-frequency transmission and reception, the I-phase Tx radio frequency mixer 216 and the Q-phase Tx radio frequency mixer 218 may not be required. One advantage of two data mixing stages is that the low / mid-frequency mixing stage components operate outside the frequency range of interest for either the high-frequency transmit path or the high-frequency receive path.

[0100]

[0109] Path switching allows the frequency-agile transceiver to switch between first-stage data mixers, enabling operation of a low / mid-frequency path, which may be amplified and transmitted as a replica of the low / mid-band signal. Path switching also allows the low / mid-band signal to be transmitted to an alternative path, which allows a second frequency mixing stage to easily create an upconverted high-band signal, which may be further amplified and then transmitted via a high-frequency antenna.

[0101]

[0110] For the receive path, the path switching can transfer the high frequency signal downconverted to a low frequency signal to the receive path towards a low / mid frequency mixing stage, where the signal can be further downconverted to obtain an IQ signal.

[0102]

[0111] When using the beamforming frequency-agile transceiver 300, focused narrow beams increase link range; focused beams require highly directional antennas connected to the transmit and receive arrays, and signals undergo phase shifts and amplitude changes. The phase shifts and amplitude changes required for beamforming are facilitated by transmit phase shifters, Tx Digital Phase Shifter 1 326a, Tx Digital Phase Shifter 2 326b, Tx Digital Phase Shifter 3 326c, and Tx Digital Phase Shifter 4 326d, and variable gain amplifiers, Tx Variable Gain Amplifier 1 328a, Tx Variable Gain Amplifier 2 328b, Tx Variable Gain Amplifier 3 328c, and Tx Variable Gain Amplifier 4 328d. In the beamforming frequency-agile transceiver 300, there is only one set of phase shifters for the transmit path and one set for the receive path, which is used when either the low / mid frequency band signals are active or the high frequency band signals are active. That is, there is a common set of phase shifters for the transmit path and a common set of phase shifters for the receive path.

[0103]

[0112] The frequency-agile transceiver architecture does not include a separate phase shifter in the high-frequency transmit or receive path. Instead, the phase shift for the high-frequency signal is performed by the same phase shifter used for the low / mid-frequency signal. This is because the high-frequency signal is downconverted to the same frequency as that of the low / mid-frequency path. As a result, both the high-frequency and low / mid-frequency paths may use the same phase shifter. This may save a significant amount of physical space on the semiconductor die and reduce path loss, since phase shifters are lossy and require extra amplification, thereby increasing power consumption. The proposed frequency-agile transceiver architecture has the advantage of fewer phase shifters and variable-gain amplifiers because both the high-frequency signal and the low / mid-frequency signal share the same phase shifter and variable-gain amplifier, e.g., Tx variable-gain amplifier 1 328a.

[0104]

[0113] For efficient operation of a frequency-agile transceiver architecture, the signal bandwidth of the low / mid frequency signals should be at least as large as the signal bandwidth of the high frequency signals. Otherwise, it may be difficult to use the low / mid frequency signals as a means for generating the high frequency signals in the case of transmit, or to use the high frequency signals for generating the low / mid frequency signals in the case of receive. If the signal bandwidth required for the low / mid frequency signals is smaller than that required for the high frequency signals, the frequency-agile transceiver architecture operates best when the low / mid frequency transmit or receive paths can support the same signal bandwidth as that of the high frequency signal bandwidth.

[0105] Mode-selectable frequency-agile transceiver

[0114] Alternative frequency agile transceivers are described with respect to Figures 8, 9, 10, and 11. Figure 8 shows a mode selectable frequency agile transmitter 800, Figure 9 shows a mode selectable frequency agile receiver 900, Figure 10 shows an alternative mode selectable frequency agile transmitter 1000, and Figure 11 shows an alternative mode selectable frequency agile receiver 1100. The mode selectable frequency agile transmitter 800, the mode selectable frequency agile receiver 900, the alternative mode selectable frequency agile transmitter 1000, and the alternative mode selectable frequency agile receiver 1100 replace portions of the beamforming frequency agile transceiver 300 of Figure 3. In Figures 8, 9, 10, and 11, transmitting elements, e.g., transmit element 1 330a, or receiving elements, e.g., receive element 1 380a, are not shown.

[0106]

[0115] Mode selectable frequency agile transmitter 800, mode selectable frequency agile receiver 900, alternative mode selectable frequency agile transmitter 1000, and alternative mode selectable frequency agile receiver 1100 may be used as part of a mode selectable frequency agile transceiver that operates in four modes: high frequency beamforming mode, low / mid frequency beamforming mode, high frequency MIMO mode, and low / mid frequency MIMO mode. The components shown in Figures 8, 9, 10, and 11 operate in two modes: beamforming mode and MIMO mode. Configuration of the mode selectable frequency agile transmitter 800, the mode selectable frequency agile receiver 900, the alternative mode selectable frequency agile transmitter 1000 and the alternative mode selectable frequency agile receiver 1100 in high frequency and low / mid frequency beamforming mode or high frequency and low / mid frequency MIMO mode is provided by at least the signal controller Tx RF switch 232 or the Rx RF switch 282.

[0107]

[0116] The high-frequency beamforming mode provides a transmitter or receiver capable of beamforming high-frequency band signals (through intermediate-frequency beamforming). Transmit beamforming is performed on I and Q data signals generated from one DAC (digital-to-analog converter) for the I phase and one DAC for the Q phase. The analog signals are transmitted over multiple lines, each of which has a common mixing stage before being phase- and amplitude-adjusted and transmitted to the transmit element. The phase and amplitude settings can be different for each line to achieve beamforming. One DAC is used for the transmitter's I phase signal, and the other DAC is used for the Q phase signal. The output of a transmit element, such as transmit element 1 330a, is set to either the mm-wave or high-band path using the Tx RF switch 232.

[0108]

[0117] For the receiver, multiple lines process the received signals. Each line has a receiving element, and one of the multiple receiving elements receives the signal. The output from the receiving element is then adjusted for phase and amplitude and sent to a receiver common mixing stage. The output from the receiver common mixing stage on each line is sent to one of two ADCs (analog-to-digital converters), one for the I phase and one for the Q phase. The receiving element, for example, receive element 1 380a, is set to either the millimeter wavelength or high frequency band path using the Rx RF switch 282.

[0109]

[0118] The low / mid frequency beamforming mode, or simply low frequency beamforming mode, provides a beamformed low / mid frequency band signal. The low / mid frequency beamforming mode operates similarly to the high frequency beamforming mode, except that the signal controller Tx RF switch 232 or Rx RF switch 282 is set to the low / mid frequency band path, as previously described.

[0110]

[0119] The MIMO mode provides MIMO (multiple-input and multiple-output) and the I and Q signals or data streams input to the mode-selectable frequency-agile transmitter include MIMO precoding. MIMO precoding ensures channel distortion and impairments are minimized to improve signal fidelity and signal-to-noise ratio at the receiver. MIMO precoding is configured for low / mid-frequency band / intermediate frequency with a fixed phase and constant gain for each line. All lines have the same or identical phase for the Tx digital phase shifter or Rx digital phase shifter and the same or identical gain for the Tx variable gain amplifier or Rx variable gain amplifier. When operating in low / mid-frequency (low frequency) MIMO mode, the Tx RF switch 232 or Rx RF switch 282 is configured to operate in the low / mid-frequency band path. When operating in high-frequency MIMO mode, the Tx RF switch 232 or Rx RF switch 282 is configured to operate in the high-frequency band path. When operating in beamforming mode, each line can have a different or independent phase and gain.

[0111]

[0120] The mode selectable frequency agile transmitter 800 can operate in beamforming or MIMO mode. The mode selectable frequency agile transmitter 800 is shown replacing a portion of the transmit path 346 of the beamforming frequency agile transceiver 300. The mode selectable frequency agile transmitter 800 has four lines, with components labeled a, b, c, and d. Each line can generate a signal for beamforming or an output in MIMO mode.

[0112]

[0121] The input section of mode selectable frequency agile transmitter 800 uses a digital signal processor 805 to provide a clock signal to a DAC (digital-to-analog converter). There are four Q-phase DACs, namely, Q-phase DACs 810a, 810b, 810c, and 810d. There are also four I-phase DACs, namely, I-phase DACs 820a, 820b, 820c, and 820d. Each line has a Q-phase DAC and an I-phase DAC.

[0113]

[0122] In MIMO mode, each of the Q-phase DACs receives a Q-phase input similar to the quadrature-phase input 204 and a clock signal from the digital signal processor 805. Similarly, the I-phase DAC receives an I-phase input similar to the in-phase input 202. The I- and Q-phase inputs can also be differential pairs, I+, I- and Q+, Q-. That is, in MIMO mode, each line has separate signal inputs for the I and Q phases. In beamforming mode, only the Q-phase digital-to-analog converter 810d and the I-phase digital-to-analog converter 820d operate, and their outputs are used for the a, b, c, and d lines. In beamforming mode, each line receives the same inputs for the I and Q phases.

[0114]

[0123] The mode-selectable frequency-agile transmitter 800 uses switches to change operation between beamforming mode and MIMO mode. There are three Q-phase MIMO / beamforming switches 830a, 830b, and 830c and three I-phase MIMO / beamforming switches 840a, 840b, and 840c. These switches may be referred to as mode switches. The I- and Q-phase switches are used to select different inputs in MIMO mode or beamforming mode. The outputs from the I-phase and Q-phase switches are sent to transmitter common mixing stages 850a, 850b, and 850c, while the outputs from the Q-phase digital-to-analog converter 810d and the I-phase digital-to-analog converter 820d are passed directly to transmitter common mixing stage 850d.

[0115]

[0124] Of the four lines, line d receives two input signals, I and Q phase inputs. The remaining lines a, b, and c are switchable between two input signals, I and Q phases, from a Q-phase digital-to-analog converter 810d and an I-phase digital-to-analog converter 820d in beamforming mode, and another MIMO input signal for MIMO mode. The other MIMO input signals are from a Q-phase digital-to-analog converter 810a, an I-phase digital-to-analog converter 820a, a Q-phase digital-to-analog converter 810b, an I-phase digital-to-analog converter 820b, and a Q-phase digital-to-analog converter 810c and an I-phase digital-to-analog converter 820c.

[0116]

[0125] Each of the transmitter common mixing stages also receives a local oscillator input 855, which represents the input from the signal combiner 206. The transmitter common mixing stages 850a, 850b, 850c, and 850d are each common mixing stages as described for the transmitter common mixing stage 700.

[0117]

[0126] When operating in MIMO mode, the mode selectable frequency agile transmitter 800 uses all of the Q-phase DACs 810a, 810b, 810c, and 810d and the I-phase DACs 820a, 820b, 820c, and 820d. The output from the I-phase digital-to-analog converter 820a is passed to the transmitter common mixing stage 850a through the I-phase MIMO / beamforming switch 840a. However, in beamforming mode, the transmitter common mixing stage 850a receives input from the I-phase digital-to-analog converter 820d. As a result, in MIMO mode, all of the Q-phase DACs 810a, 810b, 810c, and 810d and the I-phase DACs 820a, 820b, 820c, and 820d are used. In beamforming mode, the outputs from the Q-phase digital-to-analog converter 810d and the I-phase digital-to-analog converter 820d are input to each of the transmitter common mixing stages 850a, 850b, 850c, and 850d. In beamforming mode, unused DACs do not need to be powered.

[0118]

[0127] The outputs from the transmitter common mixing stages 850a, 850b, 850c, and 850d are sent to phase shifters, i.e., Tx digital phase shifters 326a, 326b, 326c, and 326d, and then to amplifiers, i.e., Tx variable gain amplifiers 328a, 328b, 328c, and 328d. The outputs from the Tx variable gain amplifiers are sent to transmit element inputs 890a, 890b, 890c, and 890d.

[0119]

[0128] In mode-selectable frequency-agile transmitter 800, line a has inputs to Q-phase digital-to-analog converter 810a and I-phase digital-to-analog converter 820a and output to transmit element input 890a. Line b has inputs from Q-phase digital-to-analog converter 810b and I-phase digital-to-analog converter 820b and output to transmit element input 890b. Line c has inputs from Q-phase digital-to-analog converter 810c and I-phase digital-to-analog converter 820c and output to transmit element input 890c. Line d has inputs from Q-phase digital-to-analog converter 810d and I-phase digital-to-analog converter 820d and output to transmit element input 890d.

[0120]

[0129] In a variation of the mode selectable frequency agile transmitter 800, when in MIMO mode, a bypass is used to bypass the phase shifters, i.e., Tx digital phase shifters 326a, 326b, 326c, and 326d, the amplifiers, i.e., Tx variable gain amplifiers 328a, 328b, 328c, and 328d, or both the phase shifters and the variable gain amplifiers. Bypassing the phase shifters, the amplifiers, or both the phase shifters and the amplifiers reduces signal loss and saves power.

[0121]

[0130] The mode selectable frequency agile transmitter 800 provides a single transmitter that can operate in a high frequency band beamforming mode, a low / mid frequency band beamforming mode, or a MIMO mode. In alternative examples, the mode selectable frequency agile transmitter 800 can have a different number of lines, such as 2, 3, 5, 6, 7, 8, etc.

[0122]

[0131] 9 shows a mode-selectable frequency-agile receiver 900 that can operate in beamforming mode or MIMO mode. The mode-selectable frequency-agile receiver 900 represents a replacement for a portion of the receive path 350 of the beamforming frequency-agile transceiver 300. The mode-selectable frequency-agile receiver 900 has four lines, with components labeled a, b, c, and d.

[0123]

[0132] The mode selectable frequency agile receiver 900 receives outputs from a receive element, e.g., receive element 1 380a, as receive element outputs 990a, 990b, 990c, and 990d. The outputs from the receive elements are sent to amplifiers, i.e., Rx variable gain amplifiers 378a, 378b, 378c, and 378d, and to phase shifters, i.e., Rx digital phase shifters 376a, 376b, 376c, and 376d, as previously described with respect to receive path 350. The outputs from Rx digital phase shifters 376a, 376b, 376c, and 376d are sent to receiver common mixing stages 950a, 950b, 950c, and 950d. Each of the receiver common mixing stages 950a, 950b, 950c, and 950d also receives a local oscillator input 955, e.g., the output from the signal combiner 206 of the beamforming frequency agile transceiver 300. When operating in beamforming mode, the Rx variable gain amplifiers 378a, 378b, 378c, and 378d and the Rx digital phase shifters 376a, 376b, 376c, and 376d can be individually configured with different or independent gain and phase shifts for each line. When operating in MIMO mode, the Rx variable gain amplifiers 378a, 378b, 378c, and 378d and the Rx digital phase shifters 376a, 376b, 376c, and 376d have the same or identical values ​​for gain and phase for each line.

[0124]

[0133] Each of the receiver-common mixing stages 950a, 950b, 950c, and 950d outputs an I-phase and a Q-phase output. The I-phase outputs of the receiver-common mixing stage 950a, the receiver-common mixing stage 950b, and the receiver-common mixing stage 950c are sent to the I-phase MIMO / beamforming switches 940a, 940b, and 940c, respectively. The Q-phase outputs from the receiver-common mixing stage 950a, the receiver-common mixing stage 950b, and the receiver-common mixing stage 950c are sent to the Q-phase MIMO / beamforming switches 930a, 930b, and 930c, respectively. The I-phase output from the receiver-common mixing stage 950d is sent directly to the I-phase analog-to-digital converter 920d, and the Q-phase output is sent directly to the Q-phase analog-to-digital converter 910d.

[0125]

[0134] I-phase MIMO / beamforming switches 940a, 940b, and 940c and Q-phase MIMO / beamforming switches 930a, 930b, and 930c select between beamforming mode and MIMO mode. When MIMO mode is selected, the outputs of the MIMO / beamforming switches are sent to individual ADCs (analog-to-digital converters). The outputs from I-phase MIMO / beamforming switches 940a, 940b, and 940c are sent to I-phase analog-to-digital converter 920a, I-phase analog-to-digital converter 920b, and I-phase analog-to-digital converter 920c, respectively. The outputs from Q-phase MIMO / beamforming switches 930a, 930b, and 930c are sent to Q-phase analog-to-digital converter 910a, Q-phase analog-to-digital converter 910b, and Q-phase analog-to-digital converter 910c, respectively. In beamforming mode, outputs from Q-phase MIMO / beamforming switches 930a, 930b, and 930c are combined and sent to Q-phase analog-to-digital converter 910d, and outputs from I-phase MIMO / beamforming switches 940a, 940b, and 940c are combined and sent to I-phase analog-to-digital converter 920d. When operating in beamforming mode, the MIMO ADC, Q-phase analog-to-digital converter 910a, Q-phase analog-to-digital converter 910b, Q-phase analog-to-digital converter 910c, I-phase analog-to-digital converter 920a, I-phase analog-to-digital converter 920b, and I-phase analog-to-digital converter 920c are unused and may be powered off.

[0126]

[0135] As described above, the mode-selectable frequency-agile receiver 900 has multiple lines, and the first of the multiple lines, line d, outputs two signals, I-phase and Q-phase. The remaining lines a, b, and c are switchable between outputting two signals when operating in beamforming mode and outputting separate MIMO output signals for I-phase ADCs 920a, 920b, and 920c and Q-phase ADCs 910a, 910b, and 910c. When operating in beamforming mode, the signals on the four lines are combined to generate one output. When operating in MIMO mode, four separate outputs are generated. As described above, the ADCs for the remaining lines can be powered off in beamforming mode.

[0127]

[0136] Each of the Q-phase ADCs 910a, 910b, 910c, and 910d and the I-phase ADCs 920a, 920b, 920c, and 920d receives a clock input from the digital signal processor 905 and outputs an I- or Q-phase output. Although the mode-selectable frequency-agile receiver 900 is described with respect to I and Q phases, differential outputs at I+, I− and Q+, Q− can also be used. The signal outputs from the Q-phase ADCs 910a, 910b, 910c, and 910d and the I-phase ADCs 920a, 920b, 920c, and 920d are not shown.

[0128]

[0137] In the mode-selectable frequency-agile receiver 900, line a receives input from receiving element output 990a and outputs to I-phase analog-to-digital converter 920a and Q-phase analog-to-digital converter 910a. Line b receives input from receiving element output 990b and outputs to I-phase analog-to-digital converter 920b and Q-phase analog-to-digital converter 910b. Line c receives input from receiving element output 990c and outputs to I-phase analog-to-digital converter 920c and Q-phase analog-to-digital converter 910c. Line d receives input from receiving element output 990d and outputs to I-phase analog-to-digital converter 920d and Q-phase analog-to-digital converter 910d.

[0129]

[0138] In a variation of the mode selectable frequency agile receiver 900, when in MIMO mode, a bypass is used to bypass the amplifiers, i.e., Rx variable gain amplifiers 378a, 378b, 378c, and 378d, the phase shifters, i.e., Rx digital phase shifters 376a, 376b, 376c, and 376d, or both the amplifiers and the phase shifters. By bypassing the phase shifters, the amplifiers, or both the phase shifters and the amplifiers, signal loss is reduced and power is saved. In an alternative example, the mode selectable frequency agile receiver 900 may have a different number of lines, such as 2, 3, 5, 6, 7, or 8.

[0130]

[0139] FIG. 10 shows an alternative mode-selectable frequency-agile transmitter 1000. The mode-selectable frequency-agile transmitter 1000 operates similarly to the previously described mode-selectable frequency-agile transmitter 800, with the exception of the difference in operation in beamforming mode. In the mode-selectable frequency-agile transmitter 800 operating in beamforming mode, the I and Q phase outputs from the Q digital-to-analog converter 810d and the I phase digital-to-analog converter 820d are also transmitted to lines a, b, and c. In the mode-selectable frequency-agile transmitter 1000, phase shifting and amplification are performed before or by the DAC. Each line can have different or independently adjustable phase and gain. In the mode-selectable frequency-agile transmitter 1000, each line has a separate DAC that is used in both MIMO mode and beamforming mode.

[0131]

[0140] The mode-selectable frequency-agile transmitter 1000 includes Q-phase DACs 1010a, 1010b, 1010c, and 1010d and I-phase DACs 1020a, 1020b, 1020c, and 1020d. The DACs receive a clock signal from the digital signal processor 1005. Each line includes a transmitter common mixing stage 1050a, 1050b, 1050c, and 1050d, which implements the transmitter common mixing stage 700 of FIG. 7A. A local oscillator input 1055 is input to each of the transmitter common mixing stages 1050a, 1050b, 1050c, and 1050d. The outputs from each of the transmitter common mixing stages 1050a, 1050b, 1050c and 1050d are transmit element inputs 1090a, 1090b, 1090c and 1090d.

[0132]

[0141] 10, the a-line has inputs from a Q-phase DAC 1010a and an I-phase DAC 1020a and outputs to a transmitting element input 1090a. The b-line has inputs from a Q-phase DAC 1010b and an I-phase DAC 1020b and outputs to a transmitting element input 1090b. The c-line has inputs from a Q-phase DAC 1010c and an I-phase DAC 1020c and outputs to a transmitting element input 1090c. The d-line has inputs from a Q-phase DAC 1010d and an I-phase DAC 1020d and outputs to a transmitting element input 1090d.

[0133]

[0142] The alternative mode selectable frequency agile transmitter 1000 is a mode selectable frequency agile transmitter that can transmit in a mode selected from the set consisting of a MIMO mode and a beamforming mode. The mode selectable frequency agile transmitter further includes a plurality of lines, each of which has the same phase when in the MIMO mode and a different or independent phase when in the beamforming mode. In alternative examples, the alternative mode selectable frequency agile transmitter 1000 can have a different number of lines, such as 2, 3, 5, 6, 7, 8, etc.

[0134]

[0143] FIG. 11 illustrates an alternative mode-selectable frequency-agile receiver 1100. The alternative mode-selectable frequency-agile receiver 1100 operates similarly to the previously described mode-selectable frequency-agile receiver 900, with differences occurring in beamforming mode. In the mode-selectable frequency-agile receiver 900 operating in beamforming mode, the I- and Q-phase outputs from the receiver common mixing stages 950a, 950b, and 950c are sent to a Q-phase analog-to-digital converter 910d and an I-phase analog-to-digital converter 920d. In the alternative mode-selectable frequency-agile receiver 1100, phase shifting and amplification are performed after or by the ADC. Each line may have different or independently adjustable phase and gain. In the alternative mode-selectable frequency-agile receiver 1100, each line has a separate ADC used in both MIMO mode and beamforming mode.

[0135]

[0144] The alternative mode selectable frequency agile receiver 1100 has receive element outputs 1190a, 1190b, 1190c, and 1190d, which are connected to receiver common mixing stages 1150a, 1150b, 1150c, and 1150d. Each of the receiver common mixing stages 1150a, 1150b, 1150c, and 1150d receives a local oscillator input 1155 similar to the local oscillator input 955. The outputs from each of the receiver common mixing stages 1150a, 1150b, 1150c, and 1150d are I- and Q-phase outputs, which are sent to I-phase ADCs 1120a, 1120b, 1120c, and 1120d and Q-phase ADCs 1110a, 1110b, 1110c, and 1110d, respectively.

[0136]

[0145] In Figure 11, the a line receives input from the receiving element output 1190a and outputs to the Q-phase ADC 1110a and I-phase ADC 1120a. The b line receives input from the receiving element output 1190b and outputs to the Q-phase ADC 1110b and I-phase ADC 1120b. The c line receives input from the receiving element output 1190c and outputs to the Q-phase ADC 1110c and I-phase ADC 1120c. The d line receives input from the receiving element output 1190d and outputs to the Q-phase ADC 1110d and I-phase ADC 1120d.

[0137]

[0146] The alternative mode selectable frequency agile receiver 1100 is a mode selectable frequency agile receiver that can receive in a mode selected from the set consisting of a MIMO mode and a beamforming mode. The mode selectable frequency agile receiver further includes a plurality of lines, each of which has the same phase when in MIMO mode and a different or independent phase when in beamforming mode. In alternative examples, the alternative mode selectable frequency agile receiver 1100 can have a different number of lines, such as 2, 3, 5, 6, 7, 8, etc.

[0138] Variations

[0147] The frequency agile transceivers described above have been described as a transmitter and receiver pair. While operating as such a pair is advantageous for enabling two-way communication between devices such as a mobile handset and a base station, frequency agile transceiver 200 and multi-beam frequency agile transceiver 300 can be modified to operate as either a standalone transmitter using transmit path 246 of frequency agile transceiver 200 and a transmit connection with signal generation chain 248, or as a standalone receiver using receive path 250 of frequency agile transceiver 200 and a receive connection with signal generation chain 248.

[0139]

[0148] As mentioned above, the low / mid frequency bands may be sub-6 GHz frequency bands at frequencies below 6 GHz or the FR1 band below 6 GHz that form part of the 5G standard for mobile communications. The high frequencies may be millimeter wavelengths (mm waves) and may include frequency ranges from 30-300 GHz or more specifically high or millimeter wavelength frequencies (FR2 bands >24-30 GHz, 37-40 GHz and >50 GHz) that form part of the 5G standard for mobile communications. Other combinations of high frequencies with low / mid frequencies are also possible.

[0140]

[0149] The beamforming frequency-agile transceiver 300 shows four transmit and receive elements as an example. Alternately, two, six, eight, or any other number of transmit and receive elements may be used. Each transmit and receive element has a corresponding phase shifter and variable gain amplifier, such as Tx Variable Gain Amplifier 1 328a and Tx Digital Phase Shifter 1 326a for the transmit path 346 or Rx Variable Gain Amplifier 1 378a and Rx Digital Phase Shifter 1 376a for the receive path 350. If there are "n" transmit elements and "n" receive elements, there are "n" phase shifters and "n" variable gain amplifiers for the transmit and receive paths, respectively. The value of "n" can be any number greater than four, such as 6, 8, etc. One limiting factor on the number of elements is how many can be physically fitted inside one die. Furthermore, for each transmit and receive element, a corresponding antenna element, phase shifter, variable gain amplifier, etc. are required. In one example, antenna elements may be shared between transmit and receive elements.

[0141]

[0150] The Tx low / mid frequency RF PA chain 234 and the Tx high frequency PA chain 240 may take the form of a general purpose single-ended power amplifier with a non-varying or constant load, or may take the form of a highly efficient architecture such as a Doherty power amplifier where the load of the constituent power amplifiers (in the Doherty) varies. The Tx low / mid frequency RF PA chain 234 and the Tx high frequency PA chain 240 may take the form of a power amplifier whose efficiency across power levels is backed off from maximum output power and maintained by an architecture similar to an envelope tracking amplifier or the like.

[0142]

[0151] The signal combiner 206 of the frequency-agile transceiver 200 and the beamforming frequency-agile transceiver 300 can be based on either a phase-locked loop or an RF oscillator. The signal combiner 206 can be a single signal source that provides a reference local oscillator signal for both the first stage dual conversion mixers for the transmit and receive paths and the second dual conversion mixing stage in the high-frequency transmit path or the high-frequency receive path.

[0143]

[0152] The signal source of the signal combiner 206 may be split into two independent signal generators or sources, each providing a reference local oscillator signal for a low / mid frequency transmit or receive path and a high frequency transmit or receive path. There is no requirement that either of these split (or independent) reference local oscillator signals must generate the same frequency, and in practice the frequencies generated by these split or independent signal sources are more likely to be different.

[0144]

[0153] Amplifiers or amplifier blocks, such as local oscillator amplifier 208, local oscillator Tx amplifier 214, local oscillator Rx amplifier 264, Tx low / mid frequency IF amplifier 222 and Rx low / mid frequency IF amplifier 272, may ensure that sufficient signal is available to drive subsequent circuits in the architecture and may in some cases be considered optional depending on the level of the input signal or based on the required output power.

[0145]

[0154] Baseband signals for frequency agile transceivers are in the form of in-phase "I" and quadrature-phase "Q" signals. Each of the I and Q signals may itself be a differential signal, denoted by I+ and I-, and Q+ and Q-, respectively.

[0146]

[0155] The local oscillator frequency multiplier 210 is optional. In one alternative, the signal combiner 206 can be split into two different signal generators, one providing the local oscillator signal for the high-frequency path of the second dual-conversion mixer stage and the other providing the local oscillator signal for the low / mid-frequency path of the first stage dual-conversion mixer. If the signal from the signal generator to the up-conversion mixer 238 or down-conversion mixer 288 is a high-frequency signal, the local oscillator frequency multiplier 210 is not needed and can be considered optional.

[0147]

[0156] In one embodiment, additional high-frequency band paths can be added to a frequency-agile transceiver, such as frequency-agile transceiver 200 or beam-forming frequency-agile transceiver 300. Additional high-frequency transmit paths can be added to the transmit elements of frequency-agile transceiver 200 or beam-forming frequency-agile transceiver 300. When adding a high-frequency transmit path, Tx RF switch 232 is changed to an appropriate switch, such as a single-pole, triple-throw switch, to select between three transmit paths: a low / mid frequency transmit path, a first high-frequency transmit path, and a second high-frequency transmit path. Each high-frequency transmit path includes an up-conversion mixer, such as up-conversion mixer 238, which receives input from a power distribution network, such as power distribution network 212 or power distribution network 312. Each high-frequency transmit path also includes a Tx high-frequency PA chain, such as Tx high-frequency PA chain 240, which can be connected to a high-frequency Tx antenna, such as high-frequency Tx antenna 242. The transmit paths may have a common antenna, as previously described with respect to the single-antenna transmit element 400. Each additional high-frequency transmit path, e.g., a second high-frequency transmit path, carries an additional high-frequency signal, such as a second high-frequency signal, that is output by at least one antenna.

[0148]

[0157] Similarly, additional receive paths can be added to the receive element of frequency-agile transceiver 200 or beamforming frequency-agile transceiver 300. When adding a high-frequency receive path, Rx RF switch 282 is changed to an appropriate switch, such as a single-pole, triple-throw switch, to select between three receive paths: a low / mid-frequency receive path, a first high-frequency receive path, and a second high-frequency receive path. Each receive path has a high-frequency LNA chain, such as high-frequency LNA chain 290, which receives input from an antenna, such as high-frequency Rx antenna 292. The output from the high-frequency LNA chain is connected to a downconversion mixer, such as downconversion mixer 288, which also receives input from a power distribution network, such as power distribution network 212 or power distribution network 312. As previously described with respect to single-antenna receive element 410 of FIG. 4B, a common antenna can be used for all receive paths. Each additional high frequency receive path, eg, a second high frequency receive path, receives an additional high frequency signal, eg, a second high frequency signal, from at least one antenna.

[0149]

[0158] Although frequency-agile transceiver 200 or beamforming frequency-agile transceiver 300 are described as transmitting and receiving either the low / mid frequency band or the high frequency band, they may also transmit the low / mid frequency band and the high frequency band simultaneously and / or receive the low / mid frequency band and the high frequency band simultaneously. Signal control devices such as Tx RF switch 232 and / or Rx RF switch 282 may be replaced with splitters or couplers to output or receive the low / mid frequency band and the high frequency band simultaneously.

[0150] Benefits and Interpretation

[0159] The above-described frequency-agile transceiver architecture supporting multi-frequency band applications is highly advantageous for small cell or macro base stations and cellular applications. The frequency-agile transceiver architecture is advantageous in having a single integrated radio transceiver (transmit and receive functions) that can simultaneously or sequentially transmit / receive signals across multiple bands, such as 5G FR1 / FR2 or WiFi radio frequencies along with 5G FR2. This is particularly beneficial in devices such as mobile handsets where separate modules are required to support different bands of the same communication standard (e.g., 5G) or different bands across two different standards (e.g., mmWave 5G + WiFi). Housing transmit / receive functions for two different bands or two different communication standards within the same chip reduces space, weight, heat dissipation, and bill of materials costs. Furthermore, in communication standards such as 5G, telecommunications operators utilize carrier aggregation, whereby portions of data are transmitted across non-contiguous bands. Carrier aggregation results in efficient utilization of spectrum resources, and frequency-agile transceiver architectures provide a single radio, or radio transmitter and / or radio receiver, that can efficiently handle data transmitted in different bands of the frequency spectrum. Carrier aggregation is a common technique in 4G and will require some technological evolution to be fully utilized in 5G systems, where a radio may transmit in low / mid-band 5G (FR1) and high-band 5G (FR2).

[0151]

[0160] Wireless transceivers that can support multiple frequency bands separated by several decades or even several octaves may also lead to more compact and energy-efficient products that can simultaneously support multiple data rates or link ranges, depending on factors such as energy consumption and efficiency. For example, incorporating mmWave transceivers and WiFi as part of the same chipset may help improve usability and enable wider adoption of multiple applications such as WiFi and high-speed fixed wireless access.

[0152]

[0161] Radio transceiver architectures, such as frequency-agile transceiver architectures, that support low-band and high-band spectrum simultaneously or sequentially can be used in multi-standard applications such as the Internet of Things. Internet-of-Things-based sensors currently rely on multiple standards defined for frequencies that coincide with low-band 5G, where low power consumption and coverage are more important than bandwidth and data rate. However, 5G also defines a mm-wave portion of the spectrum for use with Internet of Things (IoT)-based sensors due to its low latency. A radio architecture that supports both low and high frequencies can easily support similar applications based on multiple communication standards.

[0153]

[0162] In this case, a single radio transceiver and / or radio receiver system operating in both the low / mid and high bands can operate the system in either mode depending on the coverage required, at the expense of a reduced data rate.

[0154]

[0163] Previous solutions address multi-band transmission primarily by controlling different transceivers used with a single antenna, such as transmitter system 100. Such solutions often cannot support widely spaced frequency bands, such as those for 5G systems. Low-band or mid-band 5G is below 6 GHz, while high-band or millimeter-wavelength 5G is above 24 GHz. Previous solutions are based on the assumption that the frequency bands are close enough together that a single antenna can be reused by switching its path between these various chipsets. Frequency-agile transceiver 200 and multi-beam frequency-agile transceiver 300 are suitable for use at both sub-6 GHz and millimeter-wavelength frequencies.

[0155]

[0164] The disclosed frequency-agile transceiver presents a single transceiver capable of operating in two different frequency bands, which are separated by a large distance, on the order of several decades. The frequency-agile transceiver can be integrated onto a single chip, thereby reducing the cost of a mobile phone or even a radio, because one chipset can access different frequency bands using one chip rather than two chips or chipsets. As such, the frequency-agile transceiver has the potential to support base stations that can house both low-frequency sub-6 GHz 5G and mm-wave 5G radios, while supporting more compact mobile phone handsets.

[0156]

[0165] A beamforming frequency-agile transceiver architecture may reduce the number of beamforming transmit and / or receive elements required to perform beamforming using two widely separated frequency bands, and may support both low / mid-band sub-6 GHz 5G signals and high-band mmWave-5G signals with a single chipset.

[0157]

[0166] A frequency-agile transceiver architecture can help reduce base station costs because high-frequency signals, such as millimeter-wavelength signals, can support higher data rates than low- / mid-frequency signals but with shorter link ranges. To provide sufficient coverage, the use of high-frequency signals requires more radios / base stations compared to low- / mid-frequency signals, thereby increasing costs in terms of installation and maintenance. At the same time, low-frequency signals have longer ranges but lower data rate capabilities compared to high-frequency signals. While base stations / radios using mm-wave 5G, high-frequency signals are beneficial for high-data-rate and short-range scenarios, base stations using low-frequency sub-6 GHz (low- / mid-band 5G) signals are advantageous for long-range but relatively low-data-rate scenarios.

[0158]

[0167] Therefore, one way to realize the benefits of high-frequency wireless networks based on 5G or 6G standards is to develop radio frequency chipsets that can be used to build radio or base station hardware that can support high-frequency band signals and low-frequency band signals. A base station / radio that supports both bands means that the base station can operate using high-frequency signals for shorter link range and high data rate conditions, and switch to low / medium frequency signals for longer link range and low data rate conditions.

[0159]

[0168] Using a single chipset, such as one with a frequency-agile transceiver architecture, to support both high-frequency and low / mid-frequency signals can reduce hardware and therefore costs.

[0160]

[0169] Similarly, for a mobile phone handset using a chipset with a frequency-agile transceiver architecture, different wireless standards, such as 3G, 4G, 5G, WiFi, and GPS, and different frequency bands across different regions or different frequency bands, may be supported. The cost and weight of the mobile phone may be reduced due to the use of fewer chipsets. Furthermore, mobile phone manufacturers may be able to reduce the cost and weight of the mobile phone by using a frequency-agile transceiver architecture to reduce the number of chipsets while also reducing heat dissipation, while addressing other concurrent issues, such as heat dissipation or heat generation by the chipset.

[0161]

[0170] Throughout this specification and the claims that follow, unless the context otherwise requires, the word "comprise" and variations thereof, such as "comprises" or "comprising," should be understood to imply the inclusion of a specified integer or step or group of integers or steps, but not the exclusion of any other integer or step or group of integers or steps.

[0162]

[0171] The reference in this specification to any prior publication (or information derived therefrom) or to any known matter is not, and should not be construed as, an acknowledgement or admission, or any form of suggestion, that the prior publication (or information derived therefrom) or known matter forms part of the common general knowledge in the field of endeavor to which this specification pertains. [Explanation of symbols]

[0163] 100 Transmitter System 110 Single Antenna 120 GSM Cellular Transmitters 130 Bluetooth transmitter 140 Ultra-wideband transmitter 200 Frequency Agile Transceiver 202 In-phase input 204 Quadrature Phase Input 206 Signal synthesizer 208 Local Oscillator Amplifier 210 Local oscillator frequency multiplier 212 Power Distribution Network 214 Local Oscillator Transmitting Amplifier 216 I-phase transmitting radio frequency mixer 218 Q-phase transmit radio frequency mixer 219 Transmission 90° Hybrid 220 Transmit input signal summing circuit 222 Transmitting low / medium frequency intermediate frequency amplifier 230 Sending Elements 232 Transmit RF Switch 234 Transmit Low / Mid Frequency RF Power Amplifier Chain 236 Low / Mid Frequency Transmitting Antenna 238 Upconversion Mixer 240 Transmit High Frequency PA Chain 242 High Frequency Transmitting Antenna 246 Transmission Route 248 Signal Generation Chain 250 receiving routes 252 in-phase output 254 quadrature output 264 Local Oscillator Receiving Amplifier 266 I-phase receiving radio frequency mixer 268 Q-phase receiving radio frequency mixer 269 ​​Receiving 90° Hybrid 270 Received input signal dividing circuit 272 Receiver low / medium frequency intermediate frequency amplifier 280 Receiving Elements 282 Receiver Radio Frequency Switch 284 Receiver Low / Mid Frequency Low Noise Amplifier Chain 286 Low / Mid Frequency Receiving Antenna 288 Downconversion Mixer 290 High Frequency Low Noise Amplifier Chain 292 High Frequency Receiving Antenna 300 Beamforming Frequency Agile Transceiver 312 Power Distribution Network 324 Transmit Power Divider Network 326a~d Transmitting digital phase shifter 328a-d Transmitting variable gain amplifier 330a~d Transmission elements 346 Transmission Route 348 Signal Generation Chain 350 receiving route 374 Receive Power Combiner Network 376a~d Receiving digital phase shifter 378a-d Receiving variable gain amplifier 380 Receiving Elements 400 Single Antenna Transmitting Elements 410 Single Antenna Receiving Element 428 Power Distribution Network Input 430 signal input 436 Transmitting antenna output switch 442 Dual Band Transmit Antenna 478 Power Distribution Network Input 480 signal output 486 Receiving antenna input switch 492 Dual Band Receiving Antenna 505 frequency selection 510 IQ signal reception 530 Medium Frequency Carrier 540 Signal Processing 550 Beamforming Processing 560 Transmission Route Selection 570 High Frequency Check 580 High Frequency Carrier Added 590 Transmitted Signal 600 Frequency Agile Receiver Process 605 Signal Reception 610 Signal Amplification 615 Frequency Selection 620 High Frequency Check 625 High Frequency Carrier Signal Rejection 630 Receive Path Selection 635 Beamforming Processing 640 Signal Amplification 645 Q signal splitting 655 Mid-Frequency Carrier Signal Rejection 660 IQ signal output 700 Transmitter common mixing stage 750 Receiver Common Mixing Stage 800 Mode Selectable Frequency Agile Transmitter 805 Digital Signal Processor 810a~d Q-phase digital-to-analog converter 820a~d I-phase digital-to-analog converter 830a~c Q-phase MIMO / Beamforming Switch 840a~c I-phase MIMO / Beamforming Switch 850a~d Transmitter common mixing stage 855 Local Oscillator Input 890a~d Transmission element input 900 mode selectable frequency agile receiver 905 Digital Signal Processor 910a~d Q-phase analog-to-digital converter 920a~d I-phase analog-to-digital converter 930a~c Q-phase MIMO / Beamforming Switch 940a-c I-phase MIMO / Beamforming Switch 950a~d Receiver common mixing stage 955 Local Oscillator Input 990a~d Receiving element output 1000 Alternative Mode Selectable Frequency Agile Transmitter 1005 Digital Signal Processor 1010a~d Q-phase digital-to-analog converter 1020a~d I-phase digital-to-analog converter 1050a~d Transmitter common mixing stage 1055 local oscillator input 1090a~d Transmission element input 1100 Alternative Mode Selectable Frequency Agile Receiver 1110a~d Q-phase analog-to-digital converter 1120a~d I-phase analog-to-digital converter 1150a~d Receiver common mixing stage 1155 Local Oscillator Input 1190a~d Receiving element output

Claims

1. 1. A frequency agile transmitter for transmitting either low or high frequency signals, comprising: a low frequency mixing stage for combining at least two input signals encoding input data, said at least two input signals being further combined with a local oscillator signal when transmitting said low frequency signals; a transmitting element for receiving an output from the low frequency mixing stage, a signal control device for selectively transmitting the output from the low frequency mixing stage to one of a low frequency transmit path for transmitting the low frequency signal and a high frequency mixing stage; a signal controller, wherein the high frequency mixing stage upconverts the output from the low frequency mixing stage with a local oscillator signal when transmitting the high frequency signal along a high frequency transmission path; at least one antenna for outputting one of the low frequency signal and the high frequency signal; Send element containing Includes a frequency agile transmitter.

2. The frequency-agile transmitter of claim 1 , wherein the signal control device is a radio frequency switch.

3. A beamforming frequency agile transmitter, the beamforming frequency agile transmitter comprising: a power divider for producing at least two outputs from the low frequency mixing stage; a plurality of digital phase shifters for adjusting the phases of the at least two outputs; a plurality of said transmit elements, each of said plurality of transmit elements receiving an output from one of said plurality of digital phase shifters; The frequency agile transmitter of claim 1 further comprising:

4. The frequency agile transmitter of claim 3 , wherein each of the plurality of transmit elements comprises an antenna for the low frequency transmit path and an antenna for the high frequency transmit path.

5. The frequency agile transmitter of claim 3 , further comprising a plurality of variable gain amplifiers, each of said plurality of variable gain amplifiers operating on one of said at least two outputs.

6. 6. The frequency-agile transmitter of claim 5, wherein the plurality of digital phase shifters and the plurality of variable gain amplifiers enable generating a narrow beam containing the high frequency signal and a narrow beam containing the low frequency signal in the far field of each of the at least one antenna of the plurality of transmit elements.

7. The frequency agile transmitter of claim 5 , wherein each of the plurality of variable gain amplifiers and the plurality of digital phase shifters has a different configuration when using the low frequency transmit path compared to the high frequency transmit path.

8. 1. A mode-selectable frequency-agile transmitter capable of transmitting in a mode selected from the set consisting of a MIMO mode and a beamforming mode, the mode-selectable frequency-agile transmitter comprising: a plurality of lines, a first of the plurality of lines receiving input of the at least two input signals, and remaining lines of the plurality of lines being switchable between the at least two input signals and a separate MIMO input signal; a plurality of digital phase shifters for adjusting the phase of each of said lines; a plurality of said transmitting elements, each of said plurality of transmitting elements receiving an output from one of said plurality of digital phase shifters and transmitting a signal from one of said lines; The frequency agile transmitter of claim 1 further comprising:

9. each of the MIMO input signals for the remaining lines is received from a corresponding digital-to-analog converter; 9. The mode selectable frequency agile transmitter of claim 8, wherein each of the digital-to-analog converters is powered off when the mode selectable frequency agile transmitter is operating in the beamforming mode.

10. 1. A mode-selectable frequency-agile transmitter capable of transmitting in a mode selected from the set consisting of a MIMO mode and a beamforming mode, the mode-selectable frequency-agile transmitter comprising: a plurality of lines, each of the plurality of lines having the same phase when in MIMO mode and an independent phase when in beamforming mode; The frequency agile transmitter of claim 1 further comprising:

11. 1. A frequency agile receiver for receiving either low or high frequency signals, comprising: a receiving element, at least one antenna for receiving the low frequency signal and the high frequency signal; a low frequency receive path for receiving the low frequency signal and a signal control device for selectively sending output from a high frequency mixing stage to the low frequency mixing stage; the high-frequency mixing stage down-converts the high-frequency signal with a local oscillator signal when receiving the high-frequency signal from the high-frequency receiving path; and a receiving element including: a low frequency mixing stage for receiving an output from the receiving element and separating at least two signals encoding data, the at least two signals being further separated from a local oscillator signal when receiving the low frequency signals; Includes a frequency agile receiver.

12. The frequency agile receiver of claim 11 , wherein the signal control device is a radio frequency switch.

13. A beamforming frequency agile receiver, the beamforming frequency agile receiver comprising: a plurality of the receiving elements, each of the plurality of receiving elements receiving at least one of the low frequency signal and the high frequency signal; a plurality of digital phase shifters, each of which adjusts the phase of an output from one of the plurality of receiving elements; a power combiner for combining outputs from the plurality of phase shifters and sending the combined signal to the low frequency mixing stage; The frequency agile receiver of claim 11 further comprising:

14. 14. The frequency-agile receiver of claim 13, wherein each of the plurality of receive elements comprises an antenna for the low frequency receive path and an antenna for the high frequency receive path.

15. 14. The frequency agile receiver of claim 13, further comprising a plurality of variable gain amplifiers, each of said plurality of variable gain amplifiers operating on the output from one of said plurality of receiving elements.

16. 16. The frequency agile receiver of claim 15, wherein the plurality of digital phase shifters and the plurality of variable gain amplifiers enable receiving a narrow beam containing the high frequency signal and a narrow beam containing the low frequency signal.

17. 17. The frequency agile receiver of claim 16, wherein each of the plurality of variable gain amplifiers and the plurality of digital phase shifters has a different configuration when using the low frequency receive path compared to the high frequency receive path.

18. 1. A mode-selectable frequency-agile receiver capable of receiving in a mode selected from a group consisting of a MIMO mode and a beamforming mode, the mode-selectable frequency-agile receiver comprising: a plurality of lines, a first of the plurality of lines outputting the at least two signals, and remaining lines of the plurality of lines being switchable between outputting the at least two signals and a separate MIMO output signal; and each line further comprises: one of the plurality of receiving elements, each of the plurality of receiving elements receiving at least one of the low frequency signal and the high frequency signal; one of a plurality of digital phase shifters, the phase shifter adjusting the phase of the output from the receiving element; 12. The frequency agile receiver of claim 11, comprising:

19. each of the MIMO output signals for the remaining lines is sent to a corresponding analog-to-digital converter; 20. The mode selectable frequency agile receiver of claim 18, wherein each of the analog-to-digital converters is powered off when the mode selectable frequency agile receiver is operating in the beamforming mode.

20. 1. A mode-selectable frequency-agile receiver capable of receiving in a mode selected from a group consisting of a MIMO mode and a beamforming mode, the mode-selectable frequency-agile receiver comprising: a plurality of lines, each of the plurality of lines having the same phase when in MIMO mode and an independent phase when in beamforming mode; The frequency agile receiver of claim 11 further comprising:

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