572 results about "Time-division multiplexing" patented technology

The invention discloses a high-resolution and low-delay audio and video transmission method and system, which realize high-quality and low-delay remote audio and video transmission by dynamically negotiating transmission resolution and self-adaptive compression coding. The method comprises the following steps: constructing a resolution negotiation matrix through extended display identification data based on receiving end equipment, and determining an optimal transmission resolution parameter; the compression ratio is dynamically adjusted in combination with network bandwidth fluctuation, a compressed data stream is generated by adopting inter-frame prediction coding, and the anti-interference capability is enhanced through forward error correction and time division multiplexing packaging; and finally, the differential signal pair is transmitted to a receiving end to be decoded and restored into a standard audio and video signal. According to the method, the transmission delay is remarkably reduced while the high-resolution image quality is ensured, the method effectively adapts to a complex network environment, the transmission distance and stability are considered, and the method is suitable for application scenes such as remote conferences and real-time monitoring which have high real-time requirements.

The invention belongs to the technical field of satellite communication and antenna arrays, and relates to a low-orbit satellite ultra-large folded array antenna beam and polarization adaptive calibration system. According to the system, through a feed network of an antenna and a coupler of a satellite-borne detection path, a Jones matrix of each array element is obtained by adopting time division multiplexing excitation, and amplitude and phase calibration in a substrate is realized by utilizing least square pseudo-inverse compensation. Self-adaptive fusion is carried out according to the energy of the left-hand and right-hand circular polarization channels, the residual error of a fusion signal and an ideal signal is calculated, and abnormal array elements are removed in combination with amplitude outlier and phase jump detection. Performing low-rank denoising and sparse correction processing on the phase residual error, calculating the plane coefficient of each substrate through weighted least square plane fitting, and realizing smoothing and compensation iteration by using Kalman filtering and phase updating constraint. And finally, correcting each array element by the spaceborne digital beam forming unit according to the calibration coefficient, thereby realizing accurate calibration of the antenna beam and polarization.

The invention relates to the technical field of bridge load tests, and provides a bridge load test crack increment change observation method and system, and the method comprises the steps: collecting prestressing tendon circumferential strain distribution data and dual-wavelength strain response data; calculating an interface bonding stiffness change parameter; pre-stress modulation effect compensation and polar coordinate system conversion are carried out on the strain response data and the rigidity change parameters, and micro-crack characteristic signals are obtained; load data and beam group arrangement parameters are collected, and a micro-crack propagation prediction model is established in combination with the interface bonding stiffness change parameters; inputting the micro-crack characteristic signal into a micro-crack propagation prediction model, and outputting a micro-crack development trend prediction result; and adjusting sampling parameters of a dual-wavelength time division multiplexing algorithm and characteristic extraction parameters of prestress modulation effect compensation according to a micro-crack development trend prediction result. According to the invention, the precision of observing the increment change of the micro-crack in the bridge load test is improved, and the automatic monitoring and prediction of the micro-crack of the prestressed concrete bridge are realized.

The invention discloses a narrowband-broadband intelligent switching method of a radar, and belongs to the field of radar signal processing. Single radar wide-narrow band function integration is achieved through resource multiplexing, self-adaptive triggering and dynamic parameter configuration, detection tracking in a default narrow band mode is achieved, switching is triggered based on manual instructions and double thresholds, hardware such as a common antenna and a T / R assembly is reconstructed through time division multiplexing and software parameters, the signal synchronization time is shortened, and the target tracking response delay time is shortened; double-radar collaborative design is not needed, and the design workload is reduced. According to the invention, double radars are combined into a single radar, the hardware cost is greatly reduced, and the method is suitable for unmanned aerial vehicle-mounted, vehicle-mounted and other space-limited scenes and military reconnaissance, civil security and protection and other tasks.

The invention relates to the technical field of motion capture and space positioning, in particular to an acoustic motion capture method and system based on a receiving end synchronization mechanism. The core innovation of the method lies in that a system structure with a receiving end as a unified time reference is constructed, and asynchronous errors of a traditional transmitting end synchronization architecture are thoroughly eliminated. In order to solve the problems that signals of multiple transmitting nodes are difficult to judge at the same moment, multi-source signals are aliasing and the like, a receiving end synchronous unified time calibration mechanism is adopted, and a mixed signal scheduling scheme combining packet time division multiplexing and intra-group code division multiplexing is adopted. The system comprises a coordinator, an ultrasonic transmitting terminal, an acoustic receiving array and the like, the coordinator provides a global clock through an IEEE 1588v2 protocol and a PPS signal, the transmitting terminal transmits an ultrasonic signal with a unique pseudo-random noise code, the receiving array separates the signal through parallel matched filtering and records an accurate timestamp, and the acoustic receiving array receives the signal through the IEEE 1588v2 protocol and the PPS signal. And finally, high-precision positioning and attitude restoration are realized through a time difference of arrival algorithm, environmental parameter correction and an inverse kinematics model.

A system and method for distinguishing targets of interest from main lobe clutter and sidelobe clutter includes an ESA or AESA divided into subarrays. A sum beam power profile is produced via one or more scans of the subarrays, and a difference beam power profile is produced via calculations involving the subarrays. A comparison of the sum beam power profile and the difference beam power profile accentuates signal power disparities between targets of interest and clutter. A threshold is then applied to isolate targets of interest. Different difference beam power profiles may be used for elevation comparisons and azimuth comparisons. Alternatively, subarrays may be selected such that the same difference beam power profile may be used for both elevation and azimuth. Scans may be time multiplexed such that data from different scans may be used to produce the sum beam power profile, the difference beam power profile, or both.

Memory devices on a memory module may include two (or more) interfaces that access non-overlapping sets of memory arrays (i.e., two pseudo-channels). The data bus directionality of each of the two pseudo-channels may be specified or required to always be in the same direction (i.e., both read, or both write). When the data bus directionalities are tied in this manner, the data buffer devices of the module may interleave / deinterleave (i.e., time-multiplex) data for communication with a host between the two pseudo-channel data busses. The data bus directionality of each of the two pseudo-channels may be independent of the directionality of the other pseudo-channel (i.e., either can read or write without regard to the data bus directionality of the other). When the data bus directionalities are independent in this manner, the data buffer devices may interleave / deinterleave data for communication with a host within each of the two pseudo-channel data busses.

According to the cooling fan motor function test system provided by the embodiment of the invention, based on a time division multiplexing mechanism of three states of driving, measurement and silence which are unified and coordinated by a control module, a motor is normally driven by a power driving board in a driving state; in a measurement state, the power driving board turns off the upper bridge arm and turns on the lower bridge arm to eliminate switching noise, and the sensor array collects current and voltage signals; in a silent state, all the power switches are turned off to create an electromagnetic silent environment for collecting noise signals. The system isolates an interference source, can complete high-fidelity acquisition of multiple parameters in continuous dynamic operation of the motor, and provides a reliable data basis for accurate performance evaluation and fault diagnosis. Therefore, the upper computer can execute reliable analysis and diagnosis, and the accuracy and reliability of a test result are improved.

The invention relates to the technical field of optical fiber wireless communication and mobile forward transmission, in particular to a digital analog optical fiber wireless forward transmission transmitting end parameter self-adaptive optimization method and system based on reinforcement learning. Decomposing the normalized wireless signal into digital parts of all levels and a final analog residual error part through multi-level modulation, and transmitting the digital parts and the final analog residual error part in a time division multiplexing manner; a receiving end represents inter-symbol interference caused by link nonlinear distortion and bandwidth limitation, and the signal-to-noise ratio of a recovery signal is calculated based on the error vector amplitude. Parameters of a transmitting end are optimized and modeled into a Markov decision process, states comprise rounding factors, scaling factors, constellation forming factors and pre-equalization filter tap coefficients of all levels, and actions are discrete increments of the parameters; a reinforcement learning agent is constructed by using a dual deep action value network, and training is updated in combination with experience playback and a target network. The reward function comprises a threshold satisfaction item and a signal-to-noise ratio change item; parameters are interactively updated in the training stage, and online self-adaptive adjustment is performed in the reasoning stage.

The invention belongs to the technical field of deterministic transmission, and particularly relates to a deterministic transmission method for a time division multiplexing passive optical network in computing power-power cooperative communication network networking, which comprises the following steps of: acquiring and identifying all time delay sensitive flows accessed to a TDM-PON (Time Division Multiplexing-Passive Optical Network), and pre-classifying periodic flows; clustering the similar periodic flow to form a shaping flow, and distributing a shaping window; calculating the least common multiple of all shaping flow periods as a super period; in a super cycle, an integer linear programming model is adopted to complete initial optimization time window distribution; carrying out secondary sorting and conflict elimination on the overlapped transmission windows, and scheduling the shaping stream by using the transmission windows after secondary optimization; the non-periodic flow is scheduled by using the idle time slot in the over-period; and continuously multiplexing a super-cycle scheduling scheme to complete a deterministic transmission process. According to the invention, high scheduling success rate, millisecond-level deterministic time delay and microsecond-level jitter control of large-scale periodic services are realized.

The invention relates to the technical field of medical equipment, and discloses an ablation method for automatically identifying impedance and adjusting an output form, which comprises the following steps: judging the contact state of each electrode pair and tissue by independently monitoring the resistance of each electrode pair and comparing the resistance with a preset threshold value, starting energy output only for the electrode pair which is in effective contact, and starting energy output only for the electrode pair which is in effective contact; therefore, energy is prevented from being released to a non-target region; in the ablation process, the real-time resistance change of the effective electrode pair is continuously tracked, when it is monitored that a preset characteristic inflection point appears on a resistance change curve, the system judges that the point reaches an ideal ablation end point, energy output of the path is independently stopped, excessive ablation is prevented, and in order to guarantee the measurement precision, the system can be used for monitoring the ablation time. Resistance monitoring and pulse electric field output adopt a time division multiplexing technology, and interference of a strong electric field on measurement is avoided. Accurate and independent contact ablation stop closed-loop control is achieved for each ablation target, and the safety and effectiveness of an operation are remarkably improved.

The invention relates to the technical field of underground detection, and discloses a low-frequency electromagnetic field detection positioning method for an underground metal target. According to the invention, a five-frequency-band time division multiplexing detection system is adopted in the frequency band of 1-100 kHz, and a special antenna is matched, so that deep target coverage within 40 meters can be realized, and shallow accurate measurement requirements can be ensured; meanwhile, distributed reference beacon nodes are deployed, parameters such as medium conductivity, dielectric constant and humidity are collected in real time, a wave velocity prediction model is constructed based on support vector regression to dynamically correct the electromagnetic wave propagation velocity, and correction errors are controlled; a time-frequency domain joint sparse reconstruction algorithm is used for separating a close-range target aliasing signal, so that an adjacent metal target can be effectively identified; finally, multi-band emission, signal receiving, medium sensing and a central processing unit are integrated to form a closed-loop cooperative system, an underground target three-dimensional model is generated, position coordinates and size and metal type attribute information are output, the system is suitable for complex scenes such as high-humidity soil and gravel layers, and the comprehensive detection performance is remarkably improved.

The invention provides a circuit for realizing multi-mode output of an ADC, and the circuit comprises a sampling sub-circuit which collects electric data signals of a plurality of ports; a time division multiplexing circulation sub-circuit sequentially and circularly obtains input signals from the electric data; the ADC is configured to convert the input signal into a digital signal; and the digital processing sub-circuit is configured to process the digital signal according to a set output mode to obtain a calculated value, compare the calculated value with a target configuration value and then output a PWM wave corresponding to the output mode, so that the problems of single output mode, insufficient precision and poor anti-interference capability of a traditional scheme are solved; the method has the advantages of supporting multi-mode output, improving the measurement precision, enhancing the anti-interference capability and realizing efficient time division multiplexing sampling.

The present application relates to the technical field of circuit, in particular to a non-mechanical touch button detection circuit and method.The non-mechanical touch button detection circuit provided by the present application comprises a plurality of external IO channels for connecting external sensors, a detection circuit main body comprising a plurality of function detection channels, at least including a capacitance detection channel and a pressure detection channel, and a programmable analog array switch configured to selectively switch any one or more of the external IO channels to the corresponding one or more function detection channels based on different detection modes, to realize multiplexing or combination of capacitance detection function, pressure detection function or capacitance and pressure fusion detection function.The present application realizes deep fusion and flexible reconstruction of capacitance detection and pressure detection through the programmable analog array switch, realizes automatic adaptation and time division multiplexing of a single chip to multiple detection modes, and improves the versatility, reliability and environmental adaptability of the touch button.

The invention provides a service scheduling method and device, a terminal, a chip and a storage medium, and relates to the field of communication, and the method comprises the steps: responding to a first communication card in the terminal to initiate a signaling service, executing a network selection resident service by a second communication card, and determining a signaling protection time period; within the signaling protection time period, the signaling service of the first communication card is scheduled, and the network selection resident service of the second communication card is suspended; and in response to the situation that the signaling protection time period is exceeded and the scheduling of the signaling service is not completed, recovering the network selection resident service, and scheduling and executing the signaling service and the network selection resident service in a time division multiplexing mode. Therefore, the stability and reliability of the signaling service of the first communication card can be ensured, and the mobility of the second communication card can also be ensured, so that the second communication card can normally carry out network selection residence related operations, and a good connection state with a network is maintained.

The invention discloses a TFDM-PON system correction method and device, and the method comprises the steps: an OLT receives a dual-polarization signal transmitted by an ONU based on time division multiplexing or time-frequency division multiplexing, the dual-polarization signal comprises a target signal sequence corresponding to X / Y polarization, and the target signal sequence is an IQ period complex signal, and an I path and a Q path of the IQ period complex signal are single-tone signals of a first frequency and a second frequency respectively; target parameters including target transmitting and receiving end frequency deviation, IQ time delays of a target transmitting end and a target receiving end and target power deviation among ONUs are calculated based on Fourier transform and frequency domain symmetry of the dual-polarization signals, so that the ONUs carry out frequency, time delay and power correction according to the target parameters. Subcarrier crosstalk caused by frequency offset in TDM uplink burst transmission, mirror image crosstalk caused by IQ imbalance and performance degradation caused by power imbalance between subcarriers are eliminated, the bit error rate is reduced, and the system robustness is improved.

The utility model discloses an alternating current electromagnetic field array detection probe based on a time division multiplexing technology, and belongs to the field of nondestructive testing. The array detection probe comprises a shell, a magnetic core fixedly mounted in the shell, an exciting coil spirally wound on the magnetic core, a sensor array module fixedly mounted in the shell and located at the lower part of the magnetic core, and a multiplexing module fixedly mounted in the shell and electrically connected with the exciting coil and the sensor array module, a detection port is formed in the shell, the magnetic cores are arranged in a U shape, the opening ends of the magnetic cores face the detection port of the shell, the multiple magnetic cores are arranged in the shell and are distributed in a linear array mode in the shell, and the axial direction of the sensor array module is parallel to the axial direction of the array distribution track of the multiple magnetic cores. According to the array detection probe, a magnetic field change signal is captured by the sensor array module and is converted into a clear and stable electric signal to be output, so that a more accurate data basis is provided for subsequent defect analysis.

The invention relates to a pre-sensing variable-stiffness flexible electronic skin based on time division multiplexing and a cooperative control method thereof, and belongs to the technical field of flexible electronics and robot sensing. Aiming at the core contradiction of magnetic field conflict between a sensing unit and a driving unit in the existing flexible electronic skin, especially the defects of function mutual exclusion between a non-interference environment required by giant magnetoresistance pre-sensing and a high-intensity magnetic field required by magneto-rheological driving and system rigidity increase and flexibility reduction caused by a traditional spatial isolation scheme, the invention provides the flexible electronic skin. The invention provides a cooperative control architecture. According to the architecture, system working time is divided into a sensing window and an execution window which are in high-frequency alternation, and sensing and driving processes which interfere with each other are physically isolated from time; and meanwhile, an event-driven interruption mechanism based on a friction electric signal is introduced, and a continuous high-rigidity mode is forcibly entered during sudden contact. Functional conflicts are solved without magnetic shielding materials, so that the electronic skin keeps excellent flexibility, and cooperative work of pre-sensing and variable stiffness is realized.

The application discloses a kind of time division multiplexing three-axis wide spectrum light source resonant type fiber-optic gyroscope detection systems and methods, belong to gyroscope optical system design field.System is constituted by optical system and signal detection system, and optical system includes a wide spectrum light source, a push-pull Y waveguide, a circulator, three mutually orthogonal transmission type fiber ring resonant cavity, two sections of delay optical fiber and a photoelectric detector;Signal detection system includes modulation and demodulation module, time division decoupling module and low-pass filter module.Three transmission type fiber ring resonant cavities are sequentially connected, and the time of optical signal reaching three fiber ring resonant cavities is different by being set delay optical fiber between adjacent two transmission type fiber ring resonant cavities.The application ingeniously designs three fiber ring resonant cavities to form three-axis integrated structure.In this way, the time difference of three-axis signals is utilized, and multiplexing in time domain can be realized without adding additional devices.

The present application belongs to the technical field of industrial vision detection, and discloses a kind of copper foil adhesive tape bubble and pinhole defect multi-light source detection method;In the process of copper foil adhesive tape transmission, through the time division multiplexing illumination of coaxial light source and multi-azimuth oblique light source, combined with the line scanning acquisition technology of transmission speed synchronization to obtain multi-lighting mode image set.Process the image distortion caused by high-speed transmission using motion blur compensation technology, and execute local contrast anomaly detection on motion compensation image to extract candidate defect area.Through calculating radial morphological features and stereoscopic protrusion discrimination features, accurate discrimination of bubble and pinhole defects is realized.The present application has self-adaptive optimization capability, can dynamically adjust light source parameters and reacquire for the area with low discrimination confidence, and output defect position, type and severity level.The present application overcomes the influence of motion blur, improves the accuracy of defect classification, and provides accurate basis for production process parameter adjustment.

The invention discloses a piezoelectric energy acquisition circuit based on a parallel synchronous switch inductor, which comprises n piezoelectric transducers, n rectification circuits, n peak detection modules, an inductor, a first diode and an energy storage capacitor, and is characterized in that each piezoelectric transducer acquires vibration energy, converts the vibration energy into alternating voltage and outputs the alternating voltage; each rectifying circuit rectifies alternating current voltage into direct current voltage to be output, the first diode prevents load current from flowing back, the energy storage capacitor is used for storing electric energy and supplying power to a load, and a one-way conduction circuit, a switching circuit and a detection device are arranged in each peak value detection module; the detection device of each peak detection module can be connected in parallel with the inductor through the switching circuit of the detection device; the piezoelectric transducer has the advantages that only the positive half-cycle peak value of the output voltage of the piezoelectric transducer needs to be detected, the number of components needed by the peak value detection module is small, the overall circuit size is reduced, the cost is reduced, inductors can be shared at the same time during expansion, a time division multiplexing mode does not need to be adopted, and the expansion performance is high.

In some aspects, an audio processor (310) may provide a set of TDM clocks (330-1, 330-2) to each digital sample rate converter (325) in a time division multiplexed (TDM) data chain (320-1, 320-2), the set of TDM clocks comprising a sample rate clock input and a bit clock input. A digital sample rate converter (325) in each TDM data chain (320-1, 320-2) is connectable to respective audio ports (I2S0 to I2S7), each of which corresponds to a stereo channel. A digital sample rate converter (325) in each TDM data chain (320-1, 320-2) may receive a digital audio input via the audio ports (I2S0 to I2S7). An audio processor (310) may receive, at one or more TDM inputs (TDM (in) 0, (TDM (in) 1), a TDM audio stream from each of the one or more TDM data chains (320-1, 320-2), where the TDM audio streams mix the digital audio input based on a sample rate clock input and a bit clock input. Numerous other aspects are described.

Embodiments of the present application provide a CXL host controller, a data transmission method and a computer. The CXL host controller comprises a CXL host bridge module and a CXL multi-port controller. The CXL multi-port controller is connected to a physical link of a CXL device. A plurality of root ports managed by the CXL multi-port controller are shared. Each root port is used to connect a corresponding CXL device. The plurality of root ports are activated in turn according to a time division multiplexing mechanism, and data transmission is performed using the physical link. The CXL host bridge module receives a processor packet in a sending direction and converts the processor packet into a CXL packet for transmission to the CXL multi-port controller. The CXL multi-port controller receives the CXL packet of the CXL host bridge module in a sending direction, and transmits a data packet corresponding to the CXL packet to a target root port indicated by a time division multiplexing signal of a current clock cycle, and transmits the data packet to the CXL device through the target root port. The CXL host controller realizes multi-port expansion, and provides higher compatibility and flexibility for CXL network and memory device expansion.

An optical transceiver (200) includes a fiber-laser transmitter (202) configured to transmit a transmit beam (206) toward a target (208) and transmitter optics (204) optically coupled to the fiber-laser transmitter. The optical transceiver also includes an optical receiver (212) configured to receive a return beam (210) and an adaptive active modifier (222) optically coupled to the optical receiver. The optical transceiver further includes a local oscillator (214) optically coupled to the optical receiver and adaptive active modifier. In addition, the optical transceiver includes at least one processing device coupled to the fiber-laser transmitter and adaptive active modifier. The at least one processing device (302) is configured to cause the optical transceiver to turn off the local oscillator during an initial time interval, emit a stream of laser pulses using the fiber-laser transmitter during the initial time interval toward the target, measure the return beam, and determine a translational velocity of the target.

The invention discloses a two-channel biorthogonal filter bank FPGA (Field Programmable Gate Array) implementation method based on matrix decomposition. The method comprises the following steps: for a two-channel biorthogonal filter bank, firstly determining an initial coefficient of a filter, then decomposing the initial coefficient into a coefficient retention sequence and a coefficient matrix, and further decomposing the coefficient matrix into a common matrix, a low-pass branch matrix and a high-pass branch matrix through common-base N-dimensional intercepted LU decomposition; the FPGA implementation scheme is designed by combining the structural characteristics of the two-channel biorthogonal filter bank and adopting the time division multiplexing technology, the number of multipliers is effectively reduced through efficient multiplexing of a multi-phase structure and the multipliers, and the hardware resource overhead in FPGA implementation is remarkably reduced. On the premise that orthogonality and reconstruction precision of the filter bank are guaranteed, operation efficiency and data throughput capacity of the system are improved, and a feasible and efficient solution is provided for FPGA implementation of a high-performance and real-time signal processing system.

The application discloses a message forwarding method and device, a first device, a second device and a storage medium. The method comprises the following steps: a first device receives a first message, the first message contains a first segment identifier (SID), the first SID is associated with the first device, the first SID contains first information, and the first information contains related information of a time division multiplexing (TDM) cross function; a TDM channel corresponding to the first message is determined by using the first SID and second information, the second information represents an association relationship between a SID and a TDM channel; and the first message is forwarded through the TDM channel corresponding to the first message.

This application provides a display device and a three-dimensional image display method. The display device includes a backlight module, a display panel, an electrically controlled phase delay device, and a time-division multiplexing control circuit. The time-division multiplexing control circuit is configured to control the display panel to alternately display left-eye parallax images and right-eye parallax images at a preset frequency, and is configured to synchronously control the electrically controlled phase delay device to switch between a first phase delay state and a second phase delay state. This causes the electrically controlled phase delay device to generate a quarter-wavelength positive phase delay in the first phase delay state and a quarter-wavelength negative phase delay in the second phase delay state, thereby converting the linearly polarized light output from the display panel into circularly polarized light with opposite rotation, achieving precise separation of the left and right eye images. The technical solution of this application reduces crosstalk between the left and right eye images and improves the resolution and clarity of the three-dimensional display.

The invention provides an antenna multiplexing method and electronic equipment. In the method, under the condition that an antenna 1 and an antenna 2 are configured for a main communication chip and an auxiliary communication chip is newly added, if the space of the electronic equipment is limited, an antenna independently belonging to the auxiliary communication chip cannot be newly added for the auxiliary communication chip. According to the electronic equipment, the main communication chip can continue to use the antenna 1, and the auxiliary communication chip and the main communication chip can perform time division multiplexing on the antenna 2 through the switch. Through reasonable time division multiplexing, the electronic equipment can reasonably distribute the use of the antenna 2 by the auxiliary communication chip and the main communication chip so as to achieve ideal communication quality.

The invention relates to the technical field of wireless communication, in particular to a wireless audio transmission method, device, system and equipment and a storage medium. In the invention, through flexible link coexistence (frequency division / time division multiplexing) and a dynamic enabling control mechanism, intelligent distribution and optimization of transmission resources of the first peripheral equipment and the second peripheral equipment in the connection isochronous flow link group are realized. According to the invention, the system can adaptively select the multiplexing mode according to the actual transmission demand and the channel condition, and combines the repeated transmission strategy, thereby effectively improving the reliability of wireless audio transmission, reducing the time delay, and better adapting to the dynamic change of the wireless channel, thereby remarkably optimizing the overall performance of the dual-device or multi-device cooperative audio transmission.

Methods, systems, and devices for wireless communications are described. In some examples, a transmitting device associated with one or more noncoherent demodulation reference signal ports may transmit data including a phase change estimation reference signal with multiple reference signal groups. In some examples, multiple different phase change estimation reference signal ports may be code-division multiplexed to transmit the phase change estimation reference signal in the same set of reference signal groups using a different orthogonal cover code for each phase change estimation reference signal port. In some other examples, the different phase change estimation reference signal ports may be used for transmitting the phase change estimation reference signal in the different time-division multiplexed sets of reference signal groups. In such cases, by assigning two phase change estimation reference signal ports to two TDM sets, the two phase change estimation reference signal ports may be time-division multiplexed.