Abstract: A method of reliably transmitting signalling tones employs a radio communication unit suitable for encoding (303) data packets. The radio has a processor (101) for processing a first signal, which processing is incompatible for use with signalling tones. The radio further includes an input device (110) for providing signals when asserted. In a preferred embodiment, when the processor (101) is enabled to process the first signal, and a user does not assert the input device (110), the radio transmits the processed first signal. On the other hand, when the processor (101) is enabled, and the user asserts the input device (110), the radio transmits (304) repeated data packets, for the duration of the assertion, which identify a particular signalling tone.

Abstract: A nozzle system for imparting compound motion, including an orbital component and a rotational component, to the discharged fluid. The nozzle system comprises a specially engineered shell surrounding a freely flexible hose of sufficient structural integrity to simultaneously exhibit two different motion characteristics to impart the compound motion to the discharged fluid. When fluid is delivered to the nozzle system, the hose moves orbitally; that is, the hose rides against the wall of the shell in a cork screwing manner. Simultaneously, the hose rotates or twists back and forth about its own axis relative to its fixed end. Both components of motion are imparted to the discharged fluid to enhance spray power and expanse.

Abstract: Within a transmitter (101), a quantity of data (201) to be transmitted is parsed into variable length, uniquely identified messages (202), which are in turn parsed into fixed-length, uniquely identified blocks (207-211). Messages are buffered and then transmitted to a receiver (103). Upon reception of a message-received communication by the transmitter (101) corresponding to a particular buffered message, that particular message is unbuffered. Upon reception of a message-partially-received communication by the transmitter (101) corresponding to a particular buffered message, those blocks corresponding to portions of the particular buffered message that were not adequately received (703) are retransmitted.

Abstract: In a multiple site communication system, a method for determining when to hand off a communication that is occurring on one communication resource to another communication resource may be accomplished in the following manner. Once a communication unit is allocated a communication resource, it begins to monitor signal usabilities of the allocated communication resource and a predetermined set of alternate communication resources. A broadcast unit associated with the allocated communication resource also monitors the signal usability of the allocated communication resource. When the signal usability of the allocated communication resource is determined to be unfavorable by the communication unit or the broadcast unit, one of the alternate communication resources is selected based on calculated signal usability, such that the communication unit can continue the communication.

Abstract: A receiver may reduce the effects of distortion when determining signal usability in the following manner. Upon receiving a signal, the receiver separates a desired component, an undesired component, and a distortion component, wherein the desired component includes the signal that was originally transmitted and the undesired component includes interference and noise. Having isolated the distortion component, it can be mitigated such that the usability of the signal received can be determined based on a ratio between the desired and undesired components.

Abstract: A diversity receiver that receives diverse modulated signals may produce a usable signal from the received modulated signals in the following manner. Two modulated signals, each including a desired component and an undesired component, are received by the diversity receiver, wherein each desired component includes an originally transmitted signal and each undesired component includes noise and interference. The diversity receiver estimates each desired and undesired component and produces the usable signal based on the estimated desired components and the estimated undesired components.

Abstract: A receiver that receives a stream of information symbols may detect the usability of the stream of information symbols received as follows. Upon receiving the stream of information symbols, the receiver separates the stream of information symbols into a desired portion and an undesired portion wherein the desired portion is the originally transmitted stream of information symbols and the undesired portion is interference and noise. From the undesired portion and the desired portion, the usability can be determined based on a ratio of the two portions.

Abstract: A channel allocation mechanism especially useful in a trunked communication system that can accommodate both voice and data signals, and that operates in true trunked manner to efficiently utilize spectral resources.

Abstract: A receiver may reduce the effects of distortion when determining signal usability in the following manner. Upon receiving a signal, the receiver separates a desired component, an undesired component, and a distortion component, wherein the desired component includes the signal that was originally transmitted and the undesired component includes interference and noise. Having isolated the distortion component, it can be mitigated such that the usability of the signal received can be determined based on a ratio between the desired and undesired components.

Abstract: Protocol convertors associated with a mobile facsimile device and a fixed-end facsimile device are used to terminate the control data and image data protocols unique to each device. The protocol convertors interface with a digital RF communication system using a radio link protocol to ensure the error-free transmission of facsimile data.

Abstract: A radio communication system controller embodies the present invention by providing extended use (306) of a communication resource (106) to a plurality of communication units. The inventive method includes the steps of assigning (402) a first communication resource to a first communication unit, and then temporarily configuring (406) the assigned communication resource as a reserved resource. The controller then receives (408), from a second communication unit, a request to transmit a second communication on the assigned communication resource. Lastly, the controller re-configures (412) the assigned communication resource to allow transmission of the second communication on the assigned communication resource.

Abstract: Multilevel angle modulated information is decoded through integral use of channel state information. In a Viterbi Algorithm Trellis Code Modulation decoder (213), channel state information indicating temporal reliability of received symbols is utilized, along with the received symbol information and the Trellis Coding rules themselves, to facilitate a most probable symbol determination. The channel state information may be received signal strength indication information. The latter can be additionally processed by, for example, time delay compensation (401), normalization (403), morphological erosion (404), linearization (406), and/or through static channel detection (408).

Abstract: An improved protocol for a radio communications system (100) having a base station (103), radio units (101), an inbound channel (107) for conveying information from the radio units to the base station, an outbound channel (105) for conveying information from the base station to the radio units, a first unit of time is defined as a microslot (201, 203, 205), and a second unit of time is defined as a slot (207), the slot comprising an integral number of consecutive and contiguous microslots. The base station sends timing information to the radio units, and indicates to the radio units when the inbound channel is idle by, first, determining when a microslot time period has expired (303) and, when this occurs, then determining when a slot time period has expired (305). If a slot has expired, the base station then determines whether the inbound channel is idle.

Abstract: A fluid jet cleaning system, particularly adapted for household use, comprises an elongated flexible hose coupled at one end through a quick-operating on-off valve to a source of pressurized water and whose other end contains a jet nozzle assembly including a head having an ejector opening for discharging a high velocity jet stream for dislodging collected debris and a rotatable spinner sleeve containing tangential openings for emitting additional jet streams that rotate and that flush the debris and provide a secondary cleansing of the drain wall surface.

Abstract: A flexible-bandwith radio is provided. Briefly, the radio is equipped with a multiplicity of modulator and demodulator units arranged to communicate on a multiplicity of discrete frequency bands. There is no need for the individual frequency bands to be contiguous. As a result, the radio is able to simultaneously supporting a multiplicity of band-limited radio channels. The radio is further equipped with a channel combiner unit and a channel divider unit to combine the individual channels to form a high-capacity aggregate channel. The aggregate channel is then provided to the user, or to a user application. In a first embodiment, the radio utilizes a multiplicity of discrete modulator, demodulator, combiner, and divider units. In a second embodiment, the radio utilizes a suitably-programmed digital signal processor to perform the equivalent modulator, demodulator, combiner, and divider functions.

Abstract: A method and apparatus are disclosed for improved channel selection in a multi-frequency radio data communications system whereby a minimum level of signal/service quality may be maintained at all times without unduly impacting channel loading considerations. Specialized idle messages are utilized in the outbound channel of the radio system which are required in any event but include added information for the monitoring remote terminals to determine channel quality and take appropriate action by selecting a new channel to operate on if channel quality falls below a preset threshold level.

Abstract: An improved fault detect algorithm and circuit is disclosed which quickly evaluates substantially all the elements within a successive approximation A/D convertor without resorting to off-line measurements. This method utilizes a small alternating offset signal injected into the correction loop in addition to the already converted value to determine whether the elements within this loop are operating properly for any in range analog input value.