【mmwave】DeviceSurvey

Time:2021-9-26

From: http://liudongdong1.github.io/

Millimeter wave (mmWave) is a special class of radar technology that uses shortwavelength electromagnetic waves. Radar systems transmit electromagnetic wave signals that objects in their path then reflect. By capturing the reflected signal, a radar system can determine the range, velocity and angle of the objects. operating at 76–81 GHz (with a corresponding wavelength of about 4 mm

0. mmWave

image-20210430193129883

Wei T, Zhang X. mtrack: High-precision passive tracking using millimeter wave radios[C]//Proceedings of the 21st Annual International Conference on Mobile Computing and Networking. 2015: 117-129.

  • mTrack:
    • record hand-writing trace from mTrack;
    • export and control mouse of a PC
    • Myscript styles for word detection

  • E-Mi:
    • model the environment as a sparse set of geometrical structures;
    • reconstruct the structure by tracing back the invisible propagation paths;
      • recover geometries of each path: AoA, AoD, length;
    • search for best topology to achieve best covery;

  • mmWave Imaging:
    • estimating object distance, curvature, boundary, and surface material;
      • fix Tx, while moving Rx to different locations; both using single-beam;
      • use reflected RSS patterns to distinguish object geometries/materials;
    • UIysses: leveraging beamforming to improve signal diversity;
      • moving co-located Tx/Rx following predefined trajectory;

1. DCA1000EVM

The DCA1000 evaluation module (EVM) provides real-time data capture and streaming for two- and four-lane low-voltage differential signaling (LVDS) traffic from TI AWR and IWR radar sensor EVMs. The data can be streamed out via 1-Gbps Ethernet in real time to a PC running the MMWAVE-STUDIO tool for capture, visualization, and then can be passed to an application of choice for data processing and algorithm development. The DCA1000EVM is a capture card for interfacing with Texas Instrument’s 77GHz xWR1xxx EVM that enables users to stream the ADC data over Ethernet. This design is based on Lattice FPGA LFE5UM85F-8BG381I with DDR3L.

  • Supports lab and mobile collection scenarios
  • Captures LVDS data from AWR/IWR radar sensors
  • Streams output in real time through 1-Gbps Ethernet
  • Controlled via onboard switches or GUI/library

1.1. LVDS over Ethernet streaming

  • Raw mode: all LVDS data is captured and streamed over ethernet;
  • Data separated mode: add specific headers to different data types; FPGA separates out different data types based on the header and streams it over ethernet interface;

Function block diagram

  • The DCA1000EVM should be connected to TI's xWR1xxx EVM through a 60-pin HD connector by using a 60-pin Samtec ribbon cable
  • The DCA1000EVM should be connected to a PC through a USB cable (J1-Radar FTDI) for configuring the xWR1xxx EVM if the mmWave Studio is used to configure the radar device. If an embedded application is used to configure the xWR1xxx EVM, then this is not required.

2. *IW mmSensor

2.1. IWR1843

The IWR1843 is an ideal solution for low-power, self-monitored, ultra-accurate radar systems in industrial applications, such as, building automation, factory automation, drones, material handling, traffic monitoring, and surveillance. Contains a TI high-performance C674x DSP for the radar signal processing. The device includes an ARM R4F-based processor subsystem, which is responsible for front-end configuration, control, and calibration.

IWR1843

  • Transmit Subsystem:
    • three parallel transmit chains, each with independent phase and amplitude control;
  • Receive Subsystem:
    • A single receive channel consists of an LNA, mixer, IF filtering, A2D conversion, and decimation. All four receive channels can be operational at the same time an individual power-down option is also available for system optimization.
    • complex baseband architecture, which uses quadrature mixer and dual IF and ADC chains to provide complex I and Q outputs for each receiver channel.

3. Tools

.1. mmWave Studio GUI

4. Application

  • Liquid and solid level sensing;
  • industrial proximity sensing, non-contact sensing for security, traffic monitoring, industrial transportation;
  • sensor fusion of camera and radar instruments for security, factory automation, robotics;
  • sensor fusion of camera and radar instruments for object identification, manipulation, and flight avoidance for security, robotics, material handling or drone devices;
  • people counting;
  • gesturing;
  • motion detection;

4.1. Automotive mmWave radar sensors

1. Front Long range radar

achieve both superior angular and distance resolution at short ranges over a wide field of view while extending out to long distances. Relying on other optical sensors may be challenging in certain weather and visibility conditions. Smoke, fog, bad weather, and light and dark contrasts are challenging visibility conditions that can inhibit optical passive and active sensors such as cameras and LIDAR, which may potentially fail to identify a target. TI mmWave sensors, however, maintain robust performance despite challenging weather and visibility conditions.

2. Ultra short range radar

mmWave sensors for low-power, self-monitored, ultra-accurate radar systems in the automotive space.

3. Medium/short range radar

allow estimation and tracking of the position and velocity of objects and can be multi-mode for objects at a distance and close-by.

4. Driver vital sign monitoring

measuring driver vital signs, such as heart rate and breathing rate. This information could enable applications to detect the fatigue state or sleepiness state of a driver.

5. Obstacle detection sensor

detect obstacles when parking or opening doors.

6. Vehicle occupant detection

TI’s scalable 60GHz and 77GHz single-chip mmWave sensors enable robust detection of occupants (adults, children, pets) inside of a car for applications including child presence detection, seat belt reminder, and more.

4.2. Industrial

5. Background

5.1. LVDS

LVDS (low voltage differential signaling) was proposed by National Semiconductor (NS, now Ti) in 1994Level standard of signal transmission mode, it usesHigh speed differential data transmission with very low voltage swing, can be achievedPoint to point or point to multipointConnection withLow power consumption, low bit error rate, low crosstalk and low radiationHas been widely used inSerial high speed data communicationSuch as high-speed backplane, cable and board to board data transmission and clock distribution, as well as communication links in a single PCB.

Differential signalUnlike a single ended signal, a signal line transmits a signal and then refers to GND as a reference for high (H) and low (L) logic levels and as a mirror flow path, differential transmissionSignals are transmitted on both transmission lines, these two signalsThe amplitude is equal, the phase difference is 180 degrees, the polarity is opposite, and they are coupled with each other

  • Easily identify small signals;
  • Highly immune to external electromagnetic interference (EMI);
  • Reducing the supply voltage not only reduces the power consumption of high-density integrated circuits, but also reduces the heat dissipation inside the chip, which helps to improve the integration. LVDS reduces supply voltage and logic voltage swing and reduces power consumption.

6. Learning resources

Swipe Up,Swipe Down, spin cw, spin ccw, letter z, x, s