Abstract: A stabilizing apparatus and method that replaces the existing shock absorber of a road vehicle that works to resist the initiation of body roll during cornering. It seeks to counter act the forces being generated by the vehicle suspension springs that exacerbate the rollover propensity of vehicles during certain steering maneuvers.

Abstract: The present invention provides a portable greenhouse structure comprising a base in the shape of a right-polygonal cylinder having a top and a bottom, wherein the base comprises a plurality of wall panels connected along abutting edges; a hemispherical roof attached to the top of the base, wherein the hemispherical roof has a polygonal hole in the apex thereof; and a polygonal panel having the same shape as the polygonal hole, wherein the polygonal panel is moveable between an open position and a closed position, and wherein the polygonal panel sealably covers the polygonal hole when in the closed position.

Abstract: The present invention provides a portable greenhouse structure comprising a base in the shape of a right-polygonal cylinder having a top and a bottom, wherein the base comprises a plurality of wall panels connected along abutting edges; a hemispherical roof attached to the top of the base, wherein the hemispherical roof has a polygonal hole in the apex thereof; and a polygonal panel having the same shape as the polygonal hole, wherein the polygonal panel is moveable between an open position and a closed position, and wherein the polygonal panel sealably covers the polygonal hole when in the closed position.

Abstract: A prefabricated bathroom module for receiving a wheeled assembly such as a wheelchair, a walker, a piece of wheeled cleaning equipment, or the like. In a preferred embodiment, the bathroom module includes two floor surfaces, a first one of which is adapted to receive liquids thereon. The first floor surface that receives the liquids is inclined toward the second floor surface so the liquid is directed toward this second floor surface. A drainage trough is positioned between the first and second floor surfaces for collecting the liquid from the first floor surface and for preventing liquid from moving between the two floor surfaces. The trough contains an aperture and drain for removing liquid collected in the trough. The bathroom module includes at least one bathroom fixture, such as a shower, which may be connected to existing plumbing in the structure in which the module is installed.

Abstract: A method and apparatus for object identification which includes a portable electronic tag reader having a transceiver capable both of reading identification information from electronic tags and transmitting collected information to a base unit for remote analysis. The system of the present invention utilizes the same transceiver to receive information from the base unit and write data to read/write electronic tags. The system of the present invention includes a transceiver for generating a modulated or unmodulated radio frequency interrogation signal, a receiver for detecting a return signal from an electronic tag and a signal processor for processing the return signal. A modulator within the portable unit combines the identification data with the radio frequency interrogation signal for transmission to a base unit through a wireless local area network. A demodulator within the portable unit extracts data and commands received from a base unit for local processing or transfer to a read/write electronic tag.

Abstract: An apparatus for sourcing an interrogation signal for use in a object identification system including a frequency hopping source for generation of an interrogation signal which is coupled to a homo dyne radio for transmission by a bi-directional antenna to a tag. Upon receipt, the tag provides a return signal that is backscatter modulated to include tag identification or other data which is processed by the sourcing system. The frequency hopping source includes a voltage controller oscillator which is driven by a pseudo random code generator for selecting one of a plurality of hopping frequencies at which the interrogation signal is to be generated based on the available bandwidth.

Abstract: The invention provides a microstrip patch antenna for emitting backscatter-modulated signals in response to a received signal. The antenna has two segments that are connected together by a switch. When the switch is ON, the antenna is a full wave length antenna with its two segments out-of-phase with each other, thus producing minimal backscatter. When the switch is OFF, the two segments of the antenna act in concert with each other to produce a backscatter-modulated signal. Multiple pairs of such antennas can be connected together to make a single antenna with increased signal power.

Abstract: A reader interrogates a transponder attached to a remote object. The transponder includes a microstrip patch antenna having two segments connected together by a switch, each segment being one-half wavelength, the antenna being a full wavelength at the frequency of the interrogating signal. In response to a control signal, the switch is opened and closed, thereby coupling and decoupling the two segments of the microstrip antenna. When the switch is in the closed position, the two segments are out-of-phase with one another, thereby producing a maximum reflected signal. When the switch is in the open position, the two segments act in concert to produce a minimum backscattered signal. The backscatter signal is thus modulated in accordance with the control signal and is received at the reader where it is subsequently decoded to identify the remote object.

Abstract: An automated vehicle parking system for a plurality of remote parking facilities that communicates with a vehicle approaching or leaving the remote facility with RF signals, or the like, that identifies the vehicle and sends the vehicle identification number, time of day, and lane number to a first computer at the remote facility for calculating the parking cost of a given vehicle based on rates for said given individual vehicle stored in the first computer of each of the plurality of remote parking facilities and having a central computer coupled to each remote facility for providing a single bill to a user of several remote facilities and advising each remote facility first computer of the total fees due for all users of that remote facility during specified periods.

Abstract: The invention provides a circuit for analyzing backscatter-modulated RF signals received from a remote transponder to determine whether the transponder is stationary or moving toward the reader or away from it and, if moving, the rate at which the transponder is coming or going. The circuit of the invention can be integrated with existing readers of the type described in U.S. Pat. No. 4,739,328 and requires only a single antenna. In response to the signal received from a transponder, the invention circuit generates three signals, each having a different phase. By analyzing the pattern and frequency of signal state changes in the three signals, the invention can determine the transponder's speed and direction of movement.

Abstract: The invention provides a reader-transponder system that prevents reading of undesired transponder signals. The reader generates a low-frequency signal that is used to supply power to the transponder. The same low-frequency signal also is used to generate a clock signal for the transponder. The reader varies the frequency of the low-frequency power signal according to a code that is unique to the reader. Because the transponder clock signal is derived from the encoded low-frequency power signal, it also varies in accordance with the reader's code. The coded transponder clock signal is contained in the modulation of the RF signal produced by the transponder. When the reader receives and decodes the RF signal, it also extracts the transponder clock signal from the received RF signal and compares variations in the extracted transponder clock signal to the code that was applied to the low-frequency power signal transmitted by the reader.

Abstract: One or more roadside collection stations (RCS) communicate over a short-range, high speed bidirectional microwave communication link with one or more in-vehicle units (IVU) associated with one or more respectively corresponding vehicles in one or more traffic lanes of a highway. At least two up-link (IVU to RCS) communication sessions and at least one downlink (RCS to IVU) communication session are transacted in real time during the limited duration of an RCS communication footprint as the vehicle travels along its lane past a highway toll plaza. Especially efficient data formatting and processing is utilized so as to permit, during this brief interval, computation of the requisite toll amount and a fully verified and cryptographically secured (preferably anonymous) debiting of a smart card containing electronic money. Preferably an untraceable electronic check is communicated in a cryptographically sealed envelope with opener.

Abstract: A low power circuit which detects low level RF signals and RF signals of varying strength and, upon detection, activates or "wakes up" RF equipment, such as an automatic vehicle identification tag, that is normally kept in a dormant state to conserve operating power between active operations. The circuit converts a detected RF signal from a dc voltage signal to an ac voltage signal by "chopping" the dc signal to a "chopped dc" square wave, the amplitude of which is proportional to that of the original dc signal voltage, which in turn is proportional to the level of the received RF signal. The chopped dc square wave is then linearly combined with a threshold reference level signal of opposite polarity and the combined signals form the input to an ac-coupled limiting amplifier. The polarity of the amplified signal is identical to that of the larger of its two input signals. A phase detector determines the polarity of the amplified signal.

Abstract: A prefabricated bathroom module for installation onto a deck of a marine vessel. The module having a floor sloped toward a drain assembly, a plurality of walls extending upward from the floor, and a ceiling attached to the top of the walls. The drain assembly has a drain trap arrangement with a drain line that extend from between the module floor and the deck of the vessel and connect to a drainage system of the vessel without penetrating through the deck. The module further having a plumbing system with water supply lines connected to the outside of the walls and routed to a common area, with control valves connected to the drain lines at the common area. An access panel mounted to a wall of the module adjacent to the control panels to provide a user easy access to the control valves. The plumbing system further including drain lines attached to the outside of the module and routing to the common area where the plumbing system of the module attaches to the drainage system of the vessel.

Abstract: The subject invention relates to a system for identifying, for writing data into and reading data out of electronic tags which may be attached to moving and moveable objects. An interrogator sends an RF signal to a remote tag, the signal including data intended to be received and stored in the tag. The tag backscatter-modulates the received signal with data temporarily and permanently stored in the tag, including data indicating the identity of the object to which the tag is attached. The interrogator has the capability of (1) recognizing the identity of the tagged object from the returned backscatter-modulated signal and (2) transmitting data to the tag only if it has data to be transmitted to that particular tagged object. This permits data to be selectively transmitted to a tag and received and stored by that tag only after the tag has been identified as a correct one to receive that data.

Abstract: This invention relates to an improved signal reader for reading signals from transponders placed on moveable objects such as ship containers, automobiles or railroad cars. The reader sends out a continuous signal, which is modified by the information contained in the transponder attached to the moveable object. Multiple antennas, each of which receive separate signals, may be multiplexed at the reader. The improved circuit of the invention provides quick recognition of the receipt of a valid signal from a transponder or, in the alternative, the absence of such a valid signal.

Abstract: An antenna in a transponder receives signals from a reader, modulates them, and reflects them back to a reader to pass the information contained in the transponder to the reader. The system includes a thin planar dielectric material having first and second opposite surfaces, preferably with the approximate dimensions of a credit card. First conductive material is disposed on the first surface of the dielectric member at a first end of the member. Second conductive material on the second opposite surface of the dielectric member at the second end of the member defines a dipole with the first material. The second material, preferably triangular in configuration, extends from the second end to a median position between the opposite ends. An electrical circuitry module on the dielectric member produces reflected signals modulated at a particular frequency from the signal transmitted by the reader to pass information contained in the transponder to the reader.

Abstract: A reader transmits interrogating rf signals to a transponder including an antenna having a particular impedance. The signals received by the antenna are converted to a direct voltage which is introduced to a first terminal of a switch such as an emitter of a semi-conductor device having conductive and non-conductive states of operation. A second terminal of the switch, such as the base of the semi-conductor device, receives a voltage variable between first and second magnitudes in accordance with a pattern of binary 1's and 0's in a data source such as a read-only memory (ROM). This pattern of binary 1's and 0's is individual to an object identified by the transponder. The variable voltage on the base of the semi-conductor device causes the emitter-collector current of the semi-conductor device to vary between first and second amplitudes. When this current has the first amplitude, the impedance of the semi-conductor device and the ROM substantially matches the antenna impedance.

Abstract: A dielectric member may be thin and planar and may have first and second opposite surfaces. An electrically conductive material is disposed on the first surface at one end of the first surface and an electrically conductive material is disposed on the second surface at the opposite end of the second surface. The conductive materials in the first and second surfaces define a first antenna operative at a first frequency. Slots are provided in the conductive material in the first surface. The slots define a second antenna operative at a second frequency greater than the first frequency. The slots include first and second slots extending in a direction transverse to the relative direction of the conductive materials on the first and second surfaces. The first and second slots may have substantially equal lengths and may be aligned with each other. The slots also include third and fourth slots extending in such relative direction and respectively communicating with the first and second slots.

Abstract: A modular sleeping unit having individual, stackable, unitary berths providing increased comfort for crew members. The berths are constructed from reinforced plastics or other materials and are dimensioned to fit through typical ship access openings. The berths can be provided with drawer units or integral storage lockers. Lighting and ventilation can be controlled from each berth.