Abstract: The present invention can be summarized by use of a diffraction limited SAR giving large integration angle and a short depth of field which gives that energy from underground targets is focused independently at different depths to enable 3d imaging. The radar device according to the invention should be implemented by considering the following parameters: Choice of the appropriate illumination geometry, i.e. elevation angle ?, and the appropriate use of low frequency diffraction limited SAR processing to obtain 3D imaging, and the choice of an appropriately low radar frequency.

Abstract: A method for acquiring targets within a search area using an electronic device is disclosed. The method involves partitioning a first acquisition time period into a plurality of range gates, simultaneously positioning one or more of the range gates within the search area during a search mode, and transmitting an energy pulse train. Upon receipt of a reflection of the transmitted pulse train, the method records a signal level of the reflected energy pulse train within the first acquisition time period. Based on the recorded signal level, the method advances one or more of the range gates by a prescribed outbound movement increment until the signal level within at least one of the range gates is above a prescribed acquisition signal level threshold.

Abstract: A method for phase calibrating antennas in a radar system is disclosed. The method comprises providing a transmit antenna and two or more receive antennas, the receive antennas each in communication with a respective receiver channel. A radio frequency pulse having a leakage pulse is transmitted from the transmit antenna. The leakage pulse is received at each of the receive antennas and respective receiver channel. The relative phase change between the receive antennas is determined by using the leakage pulse as a reference signal.

Abstract: A pair pulse generator generates one pair of pulses including a first pulse having a predetermined width and a second pulse having a width equal to that of the first pulse and being behind from the first pulse by preset time each time a transmission designation signal is received. A burst oscillator performs an oscillation operation in a period in which one pair of pulses are input to output a signal having a predetermined carrier frequency as a first burst wave in synchronism with the first pulse and also output the signal of the predetermined carrier frequency as a second burst wave in synchronism with the second pulse, and stops the oscillation operation in a period in which one pair of pulses are not input. A transmitting unit emits the first burst wave into an exploration target space as a short pulse wave. A receiving unit receives a reflected wave and detects the second burst wave as a local signal. A control unit variably controls an interval between the first pulse and the second pulse.

Abstract: A radio communication arrangement including a plurality of transceivers and a distance measurement managing circuit. The distance measurement managing circuit is situated in a communication layer higher than the physical layer, is coupled with the plurality of transceivers, and controls the plurality of transceivers for measuring the distances of the respective plurality of transceivers to a specified position. The distance measurement managing circuit also receives and processes distance measurement values determined by the plurality of transceivers.

Abstract: A device and system for use in the early stages of search and recovery after a disaster. The device incorporates a GPS and a radio with very simplified, pre-programmed instructions which are uploaded automatically in the device's memory via wireless technology prior to the unit's first use at a disaster site. Maps of areas to be searched are uploaded into the device and the areas covered during the search are retained in the devices' memory. A unique feature enables the searcher to quickly indicate a specific need or service at a particular location during the search. Via wireless technology Areas that have been searched during a day are downloaded to a base unit and areas to be searched the following day are uploaded to the portable units at the beginning of the day. Radios on the units enable the searchers to audibly communicate with each other.

Abstract: A method for GPS navigation which uses an interacting multiple-model (IMM) estimator with a probabilistic data association filter (PDAF) improves navigation performance. The method includes (a) providing two or more models of GPS navigation, with each model characterized by a model state vector which is updated periodically, (b) providing for each model a corresponding filter for deriving, for each period, a current value for the corresponding model state vector based on current measurements made on parameters affecting the corresponding state vector; and (c) applying an interacting multiple model (IMM) estimator to provide, for each period, a current value for a system state vector using the current values of the model state vectors for that period and their corresponding filters. Each model state vector may include one or more of the following: variables: 3-dimensional position, 3-dimensional velocity, satellite clock bias, satellite clock drifts and one or more other satellite parameters.

Abstract: A device is provided, which uses a positioning system, to determine a first geographic location, while the device is located at the first geographic location. Information concerning the first geographic location may be stored in a computer memory. The device may be moved from the first geographic location to a second geographic location which is substantially different from the first geographic location. The device may be used to determine the second geographic location, while the device is located at the second geographic location. Information concerning the second geographic location may be stored in a computer memory. Directions from the second geographic location to the first geographic location may be provided by the device to a user. The directions may be displayed on a computer monitor or provided orally by use of a voice system.

Abstract: One embodiment of the present invention provides a method of creating a set of spreading codes for use in a satellite navigation system comprising a constellation of satellites. Each satellite in the constellation is to be allocated a spreading code from the set of spreading codes. The method comprises generating an initial set of bit patterns (105), where each bit pattern represents a potential spreading code, and performing an optimisation process on the initial set of bit patterns (110). The optimisation process modifies at least some of the bit patterns in the initial set to create a final set of bit patterns for use as the set of spreading codes (115) for the satellite navigation system Receivers that support the satellite navigation system incorporate the final set of bit patterns for use in signal acquisition and position determination.

Abstract: An automatic GPS tracking system is taught that consists of a GPS tracking unit secured to a person or an asset that includes a GPS receiver and a first battery operated a processor and first RF transceiver which emits an RF signal. A home base station receives the RF signal within a pre-selected proximity communication distance. A monitoring station which is in communication from a cellular modem or a satellite modem within the GPS tracking unit such that, if a person or asset having the tracking system secured thereon moves beyond the a pre-selected proximity communication distance from a home base unit, the first transceiver RF communication signals is lost, the processor automatically powers “on” the second battery to power up the GPS receiver and the cellular modem, and the GPS tracking unit may signal the monitoring station which displays the location of the person or asset.

Abstract: The present invention is directed to utilizing monitoring devices (200) for determining the effectiveness of various locations, such as media display locations (150) for an intended purpose (media display exposure). The monitoring devices (200) are distributed to a number of study respondents. The monitoring devices (200) track the movements of the respondents. While various technologies may be used to track the movements of the respondents, at least some of the location tracking of the monitoring device (200) utilize a satellite (105) location system such as the global positioning system (“GPS”). These movements of the respondent and monitoring device (200) at some point coincide with exposure to a number of media displays (150). Geo data (movement data) collected by the monitoring devices, is downloaded to a download server (300), for determining which media displays (150) the respondent was exposed to. The exposure determinations are made by a post-processing server (400).

Abstract: The present invention relates to a mobile crane having means for wireless reception or for the determination of data identifying the location of the crane as well as having transmission means which are in communication with these means or can be connected to them, wherein the transmission means are configured such that they transmit the data identifying the location of the crane from the crane to a receiver in a wireless manner.

Abstract: Radiolocalization receiver with a massively parallel array of correlators, comprising a data compression module (199) to compress the incoherent integration values accumulated into the incoherent integration memories (176). By compressing incoherent integration values, relevant memory saving can be obtained or, in alternative, loss of data by excessive prescaling can be avoided or attenuated. The invention proposes a simple compression scheme based on offset subtraction which allows save memory size.

Abstract: Estimation calculations for calculating an estimated present position are performed twice corresponding to each satellite set. The estimated present position calculated by the second estimation calculations is determined to be a present position candidate corresponding to the target satellite set. In the first estimation calculations corresponding to the first satellite set, the calculated satellite position and estimated pseudo-range of each GPS satellite are stored in caches. In the second estimation calculations, the satellite position of each GPS satellite is read from the cache. In the first estimation calculations corresponding to the second or subsequent satellite set, the satellite position and the estimated pseudo-range of each GPS satellite are read from the caches, and the satellite position and the estimated pseudo-range of the GPS satellite of which the satellite position and the estimated pseudo-range have not been stored in the caches are calculated and stored in the caches.

Abstract: In the first positioning, a positioning process that calculates the present position based on acquired GPS satellite signals (step A3) is performed a plurality of times. A number of times that the difference (position difference) ?P between the calculated present located position and the preceding located position is successively equal to or less than a given value is counted using a position counter, and a number of times that the difference (time difference) ?T between the present time error and the preceding time error is successively equal to or less than a given value is counted using a time counter each time the positioning process is performed (step A5). A position threshold value and a time threshold value are determined by changing a reference threshold value by an amount corresponding to an APR average value (step A7).

Abstract: A system for correcting angular velocity measurements from a gyroscope and using the corrected angular velocity measurements to position an antenna used with a vehicle. The system determines an approximate null point voltage of a gyroscope of the type that produces a voltage related to an angular velocity to be measured by the gyroscope. The approximate null point is determined by sampling the output voltage to obtain a plurality of sampled voltages and choosing an approximate mode of the plurality of sampled voltages as the approximate null point voltage.

Abstract: An antenna has multiple antenna elements, with a beam forming Butler matrix, having antenna ports and input/output ports, with each of said antenna elements being connected to a respective port of the beam forming Butler matrix. Transceiver circuitry is connected to each of the input/output ports of the beam forming matrix by means of respective distinct transmit and receive paths and a respective duplexer. Individually controllable gain control elements are located in each of the transmit and receive paths. These can be controlled in response to signal strength measurements made by the antenna.

Abstract: A wireless IC device includes a spiral line electrode portion and a first capacitance electrode connected to the inner end of the line electrode portion, which are disposed on the top surface of a substrate. A second capacitance electrode opposing the first capacitance electrode and a cross line electrode, which connects the second capacitance electrode and a connecting portion that connects the top and bottom surfaces, are disposed on the bottom surface of the substrate. The connecting portion electrically connects the outer end of the line electrode portion and an end of the cross line electrode. A wireless IC is mounted such that terminal electrodes thereof are connected to the connecting portion and an end of a radiating electrode. A radiating/resonating electrode including the line electrode portion, the capacitance electrodes, and the cross line electrode can act both as a resonant circuit for a resonant tag and as a radiating electrode serving as an RFID tag.

Abstract: An antenna device is provided that includes a ground and an element including a first element component part and a second element component part. The first element component part has a first end facing a side of the ground and serving as a connection point, and extends from the first end in a direction, away from the ground. The second element component part is connected to a second end of the first element component part so as to extend substantially parallel to the side of the ground part.

Abstract: A mobile terminal is disclosed. With a mobile terminal which includes a printed circuit board, a first cover and a second cover which house the printed circuit board, and an antenna pattern which is formed on an inner surface of one of the first cover and the second cover and which is connected to the printed circuit board, where the antenna pattern is formed from conductive ink, the volume of the mobile terminal can be reduced, and because there is no need to fabricate a cast, it is easy to alter the antenna pattern.

Abstract: A NFC communicator or NFC communications enabled device (100) has a data store (108) to store data, an inductive coupler (102) to couple inductively with the magnetic field of a radio frequency signal and a signal supplier (109) to supply a radio frequency signal to the inductive coupler. A modulator (110) is provided to modulate a radio frequency signal in accordance with data and a demodulator (114) is provided to extract data from a modulated radio frequency signal inductively coupled to the coupler A controller (107) enables the NFC communicator or NFC communications enabled device both to initiate near field radio frequency communication with another near field RF communicator and to respond to near field radio frequency communication initiated by another near field RF communicator.

Abstract: A multiple-element antenna for a wireless communication device is provided. The antenna comprises a first antenna element having a first operating frequency band and a floating antenna element positioned adjacent the first antenna element to electromagnetically couple to the first antenna element. The floating antenna element is configured to operate in conjunction with the first antenna element within a second operating frequency band. A feeding port connected to the first antenna element connects the first antenna element to communications circuitry and exchanges communication signals in both the first operating frequency band and the second operating frequency band between the multiple-element antenna and the communications circuitry. In a wireless mobile communication device having a transceiver and a receiver, the feeding port is connected to both the transceiver and the receiver.

Abstract: In one embodiment, a system includes a first cold noise source, a first radiometer receiver, and a first detector. The first cold noise source generates a first thermal radiation signal having a first carrier frequency band. The first thermal radiation signal carries a first information signal. The first cold noise source also transmits the first thermal radiation signal through a first antenna. The first radiometer receiver receives the first thermal radiation signal through a second antenna, and the first detector extracts the first information signal from the first thermal radiation signal.

Abstract: An antenna array (501) for use in an aviation application setting comprises an external covering (503) and at least four radio frequency antennas that are disposed underneath and that are protected by the external covering. This external covering is at least partially permeable to radio frequency signals and will provide at least a substantial barrier against external moisture and objects that might otherwise harm the antennas. This external covering is also configured and arranged to be disposed, at least in part, in a fixed position proximal to an exterior surface (206) of an aircraft. The four radio frequency antennas are electrically discrete from one another and are each configured and arranged to receive radio frequency signals for a corresponding different radio frequency platform. These four radio frequency antennas are also configured and arranged as an integral mechanical structure.

Abstract: An antenna element 1 is installed at a glass part 5 of a vehicle 4. The antennal element 1 has a ground part 3 and a radiating element 2. A metallic part side ground part 3b of the ground part 3 is overlapped with a metallic part 6 of the vehicle 4, while a glass part side ground part 3a of the ground part 3 and the radiating element 2 are not overlapped with the metallic part 6. The ground part 3 is installed such that a ratio of the area of the glass part side ground part 3a to be overlapped with the glass part 5 to the area of the metallic part side ground part 3b to be overlapped with the metallic part 6 is from 1:5 to 1:10.

Abstract: A diversity antenna system may receive transmitted signals. The diversity antenna system includes multiple phase diversity antenna elements. One or more of the phase diversity antenna elements are positioned substantially parallel to an external surface of a vehicle. The phase diversity antenna elements are adapted to receive phase diversity signals.

Abstract: A high frequency wave glass antenna for an automobile includes an antenna conductor adapted to be disposed in or on an automobile window glass sheet, the antenna conductor being formed in such a loop shape that a portion of the loop shape is cut out by a length to dispose a discontinuity, both ends of the discontinuity or portions of the antenna conductor close to the discontinuity serving as feeding points, and a portion of the antenna conductor with the discontinuity disposed therein or a portion of the antenna conductor close to the discontinuity having a conductor width of 8.0 to 40 mm.

Abstract: The present invention comprises an antenna device for a portable radio communication device operable in at least a first and a second frequency band. The antenna device comprises a first electrically conductive radiating element having a feeding portion connectable to a feed device (RF) of the radio communication device for feeding and receiving radio frequency signals, a first ground plane portion arranged at a distance from the first radiating element, a second ground plane portion, and a controllable switch arranged between the first and second ground plane portion for selectively interconnecting or disconnecting the first and second ground plane portion.

Abstract: The invention concerns an inductor comprising a plurality of so-called first conductors (100 to 109) substantially parallel to one another, at least three of said first conductors being substantially mutually equidistant and distributed over a surface (120), and an electric power supply (140) of said conductors adapted to circulate an electric current in the same direction in said conductors. Preferably, said conductors are more densely distributed at the ends of the surface (120) comprising them. Preferably, the inductor further comprises a plurality of second substantially parallel conductors perpendicular to the first conductors, the electric power supply circulating an electric current in the same direction on said second conductors. Preferably, the inductor further comprises a plurality of third conductors forming closed turns, the electric power supply circulating an electric current in the same direction in said third conductors.

Abstract: Antenna assembly for satellite tracking system that includes a plurality of antenna arrangements, each having one or more ports, and all ports connected through transmission lines in a combining/splitting circuit. The antenna arrangements form a spatial element array able to track a satellite in an elevation plane by mechanically dynamically rotating the antenna arrangements about transverse axes giving rise to generation of respective elevation angles and dynamically changing the respective distances between the axes whilst maintaining a predefined relationship between said distances and the respective elevation angles. The combining/splitting circuit provides phasing and signal delay in order to maintain pre configured radiating parameters. The arrangements can be mounted on a rotating platform to provide azimuth tracking. The system provides dynamic tracking of satellite signals and can be used for satellite communications on moving vehicles.

Abstract: An enclosed satellite antenna system can include a generally rigid enclosure defining a volume that is configured to enable both manual transportability of the satellite antenna system and automated operation of the satellite antenna system without a substantial change in the volume of the enclosure or manual repositioning of the satellite antenna system. The enclosure can have disposed therein a satellite dish, a feedhorn configured to collect incoming signals concentrated by the satellite dish, and a low noise block converter configured to receive incoming signals from the feedhorn, amplify and convert the incoming signals to received signals, and transmit the received signals to at least one receiver. A motorized elevation dravie system can be configured to selectively adjust an elevation of the satellite dish and a motorized azimuth drive system can be configured to selectively rotate the satellite dish.

Abstract: A hybrid slot-strip antenna apparatus, and an associated methodology, for a multi-mode mobile station or other radio device. The antenna is formed of a plurality of slot-strips disposed upon a printed circuit board, or other substrate. The antenna is defined by width and length design parameters, the selections of which are determinative of the antenna functionality. Through appropriate selection of the design parameters, the antenna is operable, that is, resonant, at each of the frequency bands of the multi-mode mobile station.

Abstract: A multiband antenna system includes a helical antenna having a first leg and a second leg wherein the first leg consists of a coaxial conductor. The multiband antenna also includes an antenna sub-system coupled to the helical antenna wherein the coaxial conductor feeds the antenna sub-system. A radome encloses components of the antenna system, and the radome may be covered by a radio-frequency transparent sock for concealment purposes.

Abstract: A phased array antenna includes a substrate that is segmented into a plurality of array tiles. An array of dipole antenna elements is formed on the substrate with each dipole antenna element positioned on a respective one of the array tiles. Each dipole antenna element includes a medial feed portion and a pair of legs extending outwardly therefrom. Adjacent legs of adjacent dipole antenna elements include respective spaced apart end portions forming a gap between the respective end portions and defined by separate tiles. A capacitor coupler is positioned at each respective spaced apart end portion of adjacent legs and bridging a gap for capacitive coupling respective spaced apart end portions of respective adjacent dipole antenna elements together.

Abstract: An antenna adapted for wireless networks and having a variably controlled stagger antenna array architecture is disclosed. The antenna array contains a plurality of driven radiating elements that are spatially arranged having each radiating element or element groups orthogonally movable relative to a main vertical axis so as to provide a controlled variation of the antenna array's azimuth radiation pattern.

Abstract: A dipole antenna is provided herein with improved performance at a lower end of the antenna's operating frequency range. According to one embodiment, the dipole antenna may include a plurality of antenna elements coupled to impedance transformer via a pair of cones and a pair of ears. The dipole antenna may also include a high-pass matching network specifically configured to improve antenna performance at the lower end of the operating frequency range. For example, a first stage of the matching network (i.e., closest to the antenna elements) may include two series capacitors, while a second stage of the matching network (i.e., furthest from the antenna elements) includes an inductor coupled in shunt between the two capacitors.

Abstract: A cladding (2) for a microwave antenna comprises at least one plate (3a, 3b, 3c, 3d) which has, in a first section plane (x=0; y=0), a cross section in the shape of a logarithmic spiral, characterized in that the plate (3a, 3b, 3c, 3d) has a cross section in the shape of a logarithmic spiral also in at least one second section plane perpendicular to the first one.

Abstract: A variable-directivity antenna according to the present invention includes at least three linear passive elements, which are arranged parallel to a Z-axis so as to surround a feed element. Each of those passive elements includes at least two element pieces, etc. that are arranged parallel to the Z-axis and switching elements, etc. of a first type. The passive element assembly further includes at least one switching element, etc. of a second type that makes two adjacent passive elements electrically continuous with each other when turned ON but electrically insulates them from each other when turned OFF. By turning ON and OFF the at least one switching element of the first type and the at least one switching element of the second type, the antenna can change its directivities.

Abstract: A radio antenna device for a radio communication terminal, e.g. a mobile phone, comprising a flat ground plane, a first monopole antenna element in the form of a meandered antenna element, and a second monopole antenna element having a folded three-dimensional box-like shape. The meandered antenna element has a first radio signal feeding point disposed at the ground plane. Furthermore, the meandered antenna element is located in the same plane as said ground plane in a direction of extension of the ground plane. The folded three-dimensional box-like shaped antenna element has a second radio signal feeding point disposed at a support member of the ground plane. Furthermore, the folded three-dimensional box-like shaped antenna element is located adjacent to said meandered antenna element. The meandered antenna element is operable in the first frequency band region and the folded three-dimensional box-like shaped antenna element is operable in the second frequency band region.

Abstract: An antenna assembly includes a base (3) and an antenna (2) disposed on the base. The antenna includes a radiating element (21) with top and bottom surfaces thereof, and the bottom surface of the radiating element abuts against and is surface mounted on the base. An arm (311) is located above the top surface of the radiating element so as to prevent the radiating element from tilting upwards excessively, and most of the radiating element is exposed outside the arm.

Abstract: An antenna mount comprising a front cylindrical mount, the front cylindrical mount having a threaded interior for installing an antenna; a flanged central portion; a base mount consisting of a hollow cylinder cut away along a longitudinal axis, leaving a half-circular cross section. The antenna mount can be installed by inserting it into an opening in the casing of a device and rotating the antenna mount until it abuts a stop stud.

Abstract: A combination of a portable computer and an antenna that can be used to receive wireless signals includes a portable computer and an antenna. One side of the casing of the screen of the portable computer is provided with a trough. The antenna has a connecting base that is pivotably connected in the trough and electrically connected with the computer. An elongated piece body extends from one end of the connecting base. The piece body is provided with electronic circuit therein for acting as a signal reception zone. Via the connecting base, the piece body is electrically connected with the portable computer. Both sides of the piece body are provided with an accommodating trough, respectively. A rod-like antenna is pivotably connected into each accommodating trough. By adjusting the angle and the position of the antenna, the portable computer can receive wireless signals.

Abstract: A MIMO antenna is disposed on a substrate. The substrate includes a first surface and a second surface. The MIMO antenna includes a first antenna and a second antenna set as mirror image to the first antenna, each of the first and the second antennas includes a radiation body, a feeding portion, and a grounded portion. The radiation portion is disposed on the first surface for transceiving electromagnetic signals. The radiation body includes a first radiation portion and a second radiation portion electronically connected to the first radiation portion. The first radiation portion is serpentine-shaped and the second radiation portion is rectangular-shaped. The feeding portion is disposed on the first surface, and electronically connected to the second radiation portion for feeding electromagnetic signals to the radiation body. The grounded portion is disposed on the second surface.

Abstract: A radio antenna device for a radio communication terminal, e.g. a mobile telephone, comprising a flat ground plane and an antenna element having a radio signal feeding point disposed at the ground plane. The antenna element has a folded three dimensional box-like shape. The inventive antenna design provides for an antenna device with compact size, which at the same time is operable in UWB (Ultra Wideband) frequency regions. The antenna device may therefore advantageously be incorporated into a portable communication terminal such as a mobile telephone.

Abstract: A joint includes a cable receiving groove to which a coaxial cable is fixed. The joint further includes, at both ends of the cable receiving groove, an element setup portion to which the antenna element can be attached and fixed and a ground setup portion to which the ground can be attached and fixed. The element setup portion includes engagement protrusions that can engage with engagement holes of the antenna element. The ground setup portion includes engagement protrusions that can engage with engagement holes of the ground. The engagement of the protrusions and the holes can define the positions of the antenna element and the ground relative to the joint and also defines a mutual position between the antenna element and the ground.

Abstract: Provided is a foldable multi-display apparatus that forms a foldable type large screen by connecting housings in which unit display panels are supported. The foldable multi-display apparatus includes a sliding member that moves the unit display panel supported by the housing towards the adjacent unit display panel when an unfolding operation is completed. The foldable multi-display apparatus can prevent scratching between the unit display panels during unfolding operations, thereby having increased reliability and lifespan.

Abstract: A method and system for virtual reality imaging is presented. The method includes placing a user in a known environment; acquiring a video image from a perspective such that a field of view of the video camera simulates the user's line of sight; tracking the user's location, rotation and line of sight; filtering the video image to remove video data associated with the known environment without effecting video data associated with the user; overlaying the video image after filtering onto a virtual image with respect to the user's location to generate a composite image; and displaying the composite image in real time at a head mounted display.

Abstract: A system for combining an overlay image with externally-displayed visual content, the system including: a tracking module to receive alignment information; an image generator module to generate the overlay image, and to align the overlay image using the alignment information; and a personal display module to superimpose the overlay image over a view of the externally-displayed visual content.

Abstract: In a plasma display and a driving method thereof, a sustain pulse of a high level voltage is supplied to a scan electrode or a sustain electrode during a sustain period using a capacitor charged to a voltage corresponding to a voltage difference between a high scan voltage and a low scan voltage. A low-voltage capacity transistor is connected between a power source and the scan electrode, the power source supplying a high level voltage to the scan electrode. Using the low-voltage capacity transistor results in reduced driving circuit costs and, in addition, the number of times that a transistor supplying the high scan voltage to the scan electrode and a transistor supplying the low scan voltage to the scan electrode is reduced, thereby reducing ElectroMagnetic Interference (EMI).

Abstract: A driver circuit for a scan electrode of a plasma display panel is disclosed. The driver circuit has reduced voltage drop in the current path used to drive the scan electrode during a sustain period. Accordingly, the circuit provides improved power efficiency and speed.