Abstract: A radio communication system includes a remote device radio, and a base station radio operable to communicate with the remote device radio at a first channel and at a second channel using non-simultaneous frequency diversity. The base station is operable to communicate with a device other than the remote device at the second channel while the remote device radio and the base station radio are communicating at the first channel. A radio using non-simultaneous frequency diversity includes an antenna, a radio frequency module coupled to the antenna such that the radio frequency module is operable to transmit or receive radio frequency signals at a first channel and signals at a second channel using the antenna, and a baseband module coupled to the radio frequency module. The baseband module operable to transmit or receive signals through the radio frequency module, such that signals transmitted or received by the radio employ non-simultaneous frequency diversity using the first channel and the second channel.

Abstract: In a television signal transmission system, CS broadcasting signals received via a master antenna are converted into intermediate frequency signals in an LNB (Low Noise Block Down Converter). The CS intermediate frequency signals then undergo conversion of the modulation format, for example, from QPSK into 64-QAM, so that CS broadcasting signals from each transponder, having a bandwidth of, for example, 27 MHz, are accommodated in a narrower bandwidth, for example, 6 MHz, which is equivalent to one channel of terrestrial broadcasting services. Then, the signals accommodated in the narrower bandwidth is frequency-shifted into a vacant frequency band in the VHF band or the UHF band. Accordingly, the CS signals accommodated in the narrower band and frequency-shifted into the vacant band are multiplexed with terrestrial broadcasting signals in the VHF and UHF bands and BS intermediate frequency signals so that all these signals are delivered to each household via a single cable.

Abstract: A method and apparatus for controlling a plurality of infrared devices (ICDs) is provided herein. A remote controller is used to generate an optical signal for controlling a plurality of ICDs. The optical signal generated by the remote controller is converted into an electrical signal by an infrared repeater device. An implementation of such a system includes a rotary mechanical switch to direct the electrical signal generated by the infrared repeater device to a light emitting diode (LED) located near one of the plurality of ICDs. The LED converts the electrical signal into an optical signal and re-transmits the optical signal to the one of the plurality of ICDs. The system allows controlling the plurality of ICDs located in a remote location without having the user commute closer to such ICDs.

Abstract: A data transmitting/receiving apparatus and method using an antenna array in a mobile communication system. A Node B measures a transmission status of each transmission antenna, classifies transmission data according to priority, and transmits to a UE high-priority data through a transmission antenna at a relatively good transmission status and low-priority data through a transmission antenna at a relatively poor transmission status.

Abstract: A fully integrated CMOS multi-element phased-array transmitter (transmitter) includes, in part, on-chip power amplifiers (PA), with integrated output matching. The transmitter is adapted to be configured as a two-dimensional 2-by-2 array or as a one dimensional 1-by-4 array. The transmitter uses a two step up-conversion architecture with an IF frequency of 4.8 GHz. Double-quadrature architecture for the up-conversion stages attenuates the signal at image frequencies. The phase selectors in each transmitter path have independent access to all the phases of the VCO. The double quadrature architecture results in two sets of phase selectors for each path, one for the in-phase (I) and one for the quadrature phase (Q) of the LO signal. The phase selection is done in two stages, with the first stage determining the desired VCO differential phase pair and the next stage selecting the appropriate polarity. An on-chip Balun is used for differential to single-ended conversion.

Abstract: This invention includes a wireless transmitter comprising an IF-signal generator that modulates input signals into those of an intermediate frequency band, signal distributors that distribute signals from the IF-signal generator, and a plurality of signal-transmission units that convert the signals distributed by the signal distributors into those of a radio frequency band, and then transmit the converted radio signals. The invention also includes a wireless receiver that receives the radio-frequency-band modulated signals and restores the signals of the intermediate frequency band. In this way, effective diversity is realized and signal interruptions are prevented. In addition, a handy, low-cost wireless communications system is provided.

Abstract: A system to communicate digital data symbols with higher than QPSK modulation comprises a transmitter and receiver. The transmitter comprises, a modulator and circuitry to split and encode the data into a first block of more significant bits and a second block of less significant bits for modulating by. The receiver receives digital data bits by iterative determination of soft estimates of bits followed by a hard decision as to what bit was intended, and comprises a first processor to provide first soft estimates of bits of the received signal, and a second processor to decode the first soft estimates and to provide second soft estimates of the bits.

Abstract: A beam shaping antenna matrix for use in wireless cell towers that is manually-configured at a patch panel by a wireless operator based on selection of a desired beam size and point of direction. The traffic matrix allows a wireless operator to sculpt and resculpt the beams to accommodate demographic or other changes preferably without a large amount of hardware or intensive processing capability.

Abstract: A receiver/transceiver includes N pieces of receiving antennas, a propagation path characterization estimator, a weight generator for interference canceller, an array processing interference canceller, a weight generator for signal estimator, a signal estimator, a transmission signal classification apparatus, and a decoding order decision apparatus. The antenna inference elimination circuit eliminates only signal component relating to transmission signal component which does not belong to groups. The signal estimator performs separation and decoding of the transmission signal belonging to the group. The transmission signal classification apparatus classifies the transmission signals from sets of the transmission antennas in which a cross-correlation value of the vector is larger than a threshold value, into one group, and classifies the transmission signal in which the cross-correlation value is smaller than the threshold value, into another group.

Abstract: Operating a wireless MIMO system to determine forward and reverse channel reciprocity matrices relating a first wireless MIMO device and a second wireless MIMO device of the wireless MIMO system includes, during each of a plurality of time intervals, determining a forward composite channel estimates and a reverse composite channel estimates between the first wireless MIMO device and the second wireless MIMO device to yield a plurality of forward composite channel estimates and a plurality of reverse composite channel estimates. Operation continues with creating a mathematical relationship between the plurality of forward composite channel estimates and the plurality of reverse composite channel estimates and the forward and reverse channel reciprocity matrices.

Abstract: A method, apparatus and system are provided for use in better optimizing switched beam, wireless communications. In some embodiments, a method is provided that receives a communication over a first wireless reverse link beam, selects a type of beam weighting control, determines a rule according to the type of beam weighting control, and determining a weighting of a forward link beam according to the rule. The method can further determine an energy of the first reverse link beam, and determine a first gain energy ratio based on the first reverse link beam energy, such that the weighting is determined by applying the first gain energy ratio to the rule. Some embodiments further determine a pilot beam configuration, wherein the rule is determined according to the pilot beam configuration and the selected type of beam weighting control.

Abstract: Techniques to correct for phase and amplitude mismatches in a radio device in order to maintain channel symmetry when communicating with another device using MIMO radio communication techniques. Correction for the amplitude and phase mismatches among the plurality of transmitters and plurality of receivers of a device may be made at baseband using digital logic (such as in the modem) in the receiver path, the transmitter path or both paths of that device. In a device, amplitude and phase offsets are determined among the plurality of radio transmitter and radio receiver paths by measuring phase and amplitude responses when supplying a signal to a transmitter in a first antenna path of the device and coupling the radio signal from a first antenna to a second antenna path of that device where the signal is downconverted by a receiver associated with the second antenna path, and similarly coupling a signal from the second antenna path to the first antenna path.

Abstract: Embodiments of the invention describe a modulator having first and second synthesizers, for example, fractional-N synthesizers, that generate first and second outphased modulated signals with aligned phases. Embodiments of the modulator may align the phases of the outphased signals using first and second feedback loops associated with first and second modulation paths of the modulator.

Abstract: Briefly, in accordance with one embodiment of the invention, an antenna may comprise a first radiating element to provide a first axis of polarization, and a second radiating element to provide a second axis of polarization. The first axis of polarization may be orthogonal or orthogonal at least in part, to the second axis of polarization. The first and second axes together may result in an omnidirectional, or at least partially omnidirectional, gain pattern for the antenna. RF signals may be propagated on the first and second axes using the same communication standard on both axes, and/or using a different communication standard on each of the axes. In accordance with one or more embodiments, the first axis of polarization may be utilized for a first MIMO communication channel, and the second axis of polarization may be utilized for a second MIMO communication channel.

Abstract: A transmit channel (gt1, h, gr2) through which a first wireless communication transceiver is to transmit to a second wireless communication transceiver can be estimated using information indicative of a relationship between the transmit channel and a receive channel (gt2, h, gr1) through which the first wireless communication transceiver receives communications from the second wireless communication transceiver. The relationship information (35) is combined (37) with further information (31) to produce an estimate of the transmit channel.

Abstract: An apparatus and method for generating an intermediate frequency (IF) to be transferred to a single sideband (SSB) generator which generates carriers using one local oscillator (LO) signal and at least two IF signals that are received. A group signal is generated which includes a non-phase-shifted signal and a phase-shifted signal to a predetermined value with respect to each IF. One of the group signals is selected and transferred to the SSB generator. Accordingly, the SSB generator performs the phase shift on the LO signal alone.

Abstract: An iterative multistage detection system and method for orthogonally multiplexing K channels onto a signal processing chain using N orthogonal sequences of length N. The K channels include a first set of N channels and a second set of M channels (the M channels being separate and distinct from the N channels), where K=N+M. In a first iteration, interference from the first set of N channels imparted on the second set of M channels is removed from the multiplexed signal, thereby enabling the symbol values associated with the second set of M channels to be reliably estimated. In a second iteration, interference from the second set of M channels imparted on the first set of N channels is removed from the first set of N channels, thereby enabling the symbol values associated with the first set of N channels to be reliably estimated.

Abstract: A first transceiver (200) sends (102) a predetermined number of blocks of data to a second transceiver, and records (104) on which of a plurality of sub-carriers each of the blocks of data is sent. The first transceiver receives (106) from the second transceiver a list of the blocks of data that were received with errors, and calculates (108) from the list a plurality of error rates corresponding to the plurality of sub-carriers. The first transceiver then determines (110) the SQE for each of the plurality of sub-carriers from the plurality of error rates, and adjusts (112) the data rate in accordance with the SQE determined for each of the plurality of sub-carriers. These processes can be implemented as a method that is facilitated by a software program.

Abstract: Apparatus, and an associated method, for selectably introducing desired levels of diversity into data communicated upon a radio communication channel to effectuate a communication service, such as a 1×EV-DV communication service. Responsive to channel conditions, the level of diversity is selected, and levels of encoding are utilized. Matching encoder and decoder apparatus are provided to sending and receiving station pairs. Encoder apparatus includes constituent encoder elements, and associated interleaver elements for interleaving data that is to be communicated by associated encoder elements. One, or more, antenna transducer elements are selectably utilized to provide spatial diversity in addition to temporal diversity.

Abstract: A direct conversion transmitter comprising two local oscillators, an in-phase and quadrature modulating signal and in-phase and quadrature modulators, adds a leakage detector and corrective algorithm with one or more digital to analog converters to generate a corrective signal. The corrective signal corrects for, minimizes, and suppresses local oscillator carrier leakage into the transmitted signal. In accordance with the invention, direct up transmitter carrier leakage is automatically measured at regular intervals during the transmit cycle. A DC correction, or a correction waveform as a function of time, is input to both the “in-phase” and “quadrature” modulators at the baseband input. The two correction signals are tuned according to a minimization algorithm to achieve the lowest possible carrier component in the spectral output of the transmitter at its ambient operating conditions and present power output level.

Abstract: Techniques are described for space-time block coding for single-carrier block transmissions over frequency selective multipath fading channels. Techniques are described that achieve a maximum diversity of order NtNr(L+1) in rich scattering environments, where Nt(Nr) is the number of transmit (receive) antennas, and L is the order of the finite impulse response (FIR) channels. The techniques may include parsing a stream of information-bearing symbols to form blocks of K symbols, precoding the symbols to form blocks having J symbols, and collecting consecutive NS blocks. The techniques may further include applying a permutation matrix to the NS blocks, generating a space-time block coded matrix having Nt rows that are communicated through a wireless communication medium. The receiver complexity is comparable to single antenna transmissions, and the exact Viterbi's algorithm can be applied for maximum-likelihood (ML) optimal decoding.

Abstract: A method is provided for operating a plurality of overlapping wireless networks such that they do not interfere with each other. This is accomplished by having each network transmit at a frequency that is offset from a base frequency by an integer multiple of an offset frequency. The offset frequency is generally a small fraction of the base frequency so that the spectral properties of each network are roughly the same. However, each network will transmit at a unique frequency with respect to all of the other overlapping networks. The offset values are preferably symmetrical around zero, and the offset for one network can be zero.

Abstract: An arrangement where a transmitter has multiple transmitting antennas that simultaneously transmit, and where the signals delivered to each transmitting antenna is processed by a space-time transmitter based on the side information that is related to the channel coefficients found between the transmitting antennas and multiple receiving antennas. The receiver's receiving antennas simultaneously receive the transmitted signals, and the signal from each receiving antenna is processed by the space-time receiver to extract the information symbols that have been transmitted. Alternative systems are possible, such as those employing frequency or code diversity, as well as those employing only one transmit antenna and multiple receive antennas (or visa versa).

Abstract: A transmit network for cellular mobile radio networks incorporates tow transmit multiplexers (122ABE) and (122CD): the first transmit multiplexer 122ABE receives a group of output signals from three transmitters (124A, 124B and 124E), and filters them in respective band-pass filters (126A, 126B and 126E); the second transmit multiplexer (122CD) receives a group of output signals from two further transmitters (124C and 124D), and filters them in respective band-pass filters (126C and 126D). The transmit frequencies in each signal group are non-adjacent, which improves isolation between transmitters provided by the filters (126). Filtered output signals from respective band-pass filters (126) are combined at filter outputs (128X and 128Y) from which signals are combined in a combiner (132) providing a degree of isolation between these outputs and enabling the signals to be combined with minimal distortion. Signals from the combiner (132) are fed via a duplexer to a transmit/receive antenna.

Abstract: The invention relates to a circuit arrangement in association with the RF unit of a wireless terminal, in which circuit arrangement the RF unit and the antenna (3) of the wireless terminal are fabricated/mounted on the same circuit board (1) and where the antenna (3) is connected to the RF unit through at least one signal line (2). In the circuit arrangement, the signal line (2) from the RF unit to the antenna (3) is electrically connected during the final assembly by means of a jumper (5) which is fabricated as part of a mechanical component (6) belonging to the terminal. With the arrangement according to the invention, the RF unit can be tested without interference from the antenna.

Abstract: A wireless transmit-only apparatus (20) can be comprised of a controller (21) that selectively controls which of a plurality of resonant devices (24 and 25) are utilized to influence the transmission carrier frequency of a transmitter (26). In a preferred embodiment at least one of the resonant devices comprises a mechanically resonant device (24) such as a surface acoustic wave device, a crystal resonator, or a ceramic resonator. In a preferred embodiment, a user interface (22) includes a plurality of independently assertable inputs. The controller responds to assertion of one of this inputs by selecting a particular set of characterizing transmission parameters (as are stored, for example, in a memory (23) and using those characterizing transmission parameters to transmit a message using a transmission carrier frequency as corresponds to use of a co-selected resonant device.

Abstract: A wireless transmission module comprises: a first transceiver used to broadcast and to receive signals in a first frequency band; a second transceiver used to broadcast and to receive signals in a second frequency band; a switching circuit used to provide a single path of transmission and to control the its switches between the first transceiver and the second transceiver; and a processing unit used to control the switching circuit to switch the path of transmission from the first transceiver to the second transceiver when using the first frequency band of signal to communicate with a wireless device is not possible.

Abstract: A radio communication system comprises a communication channel between a transmitter (108) having a plurality of antennas (110) and a receiver (114) having at least one antenna (110). In such a system the communication channel comprises a plurality of paths (112) having a range of characteristics. Data for transmission is generated by one or more applications (102) and has one or more categories assigned to it, for example by the addition of tags by a tagging block (204) indicating its importance or other requirements. Depending on the assigned categories and the characteristics of the paths (112), the data is mapped to one or more of the transmitter's antennas (110) to select a suitable transmission path (112).

Abstract: A transmitter receivable by broadcast band receivers in nearby vehicles, comprising a first signal generator for simultaneously providing a plurality of selectively spaced carriers having frequency spacings corresponding to the individual channels of the band to be covered and selectively providing amplitude modulation when used for the AM broadcast band, and a second signal generator providing an FM modulated signal, which when combined with the signal from the first signal generator, covers various portions of the FM broadcast band to provide complete coverage thereof. A plurality of signals are generated in a portion of a selected band and modulated, according to the selected band mode, with a pre-stored and selectable voice alarm message.

Abstract: Input signals of each frame are encoded by mapping the signals onto a coordinate system dictated by the symbols of the previous frame, and symbols from a constellation are selected based on the results of such mapping. Received signals are detected by preprocessing the signals detected at each antenna with signals detected by the antenna at the immediately previous frame, and then applied to a maximum likelihood detector circuit, followed by an inverse mapping circuit.

Abstract: The present invention provides a method of calibrating a wireless tracking system and a method of tracking a mobile unit in a wireless local area network. The method includes providing at least one calibration signal using a mobile unit having a first plurality of antennae while the mobile unit is proximate at least one predetermined location and receiving a plurality of signals at a second plurality of antennae in response to providing the at least one calibration signal. The method also includes determining a portion of a transmission matrix using the plurality of received signals and the at least one calibration signal and associating the portion of the transmission matrix with the predetermined location.

Abstract: Methods and apparatus for scheduling mobile stations (MSs) to download data and/or to control the rate of downloading to an MS from a base station (BS) as a function of downlink channel condition information are described. Artificial channel variations, which can be measured at the MS, and feedback to a BS for scheduling purposes, are introduced through the use of two or more transmitter antennas at a BS. Each of the antennas transmits a signal at the same frequency having the same information content, e.g., modulated data. However the signals are made to differ with time in their phase and/or amplitude to introduce what appear to be channel variations to the MSs.

Abstract: A method and system for optimizing the use of antennae in a CDMA distributed antenna system. A pathway manager may identify and select an optimal antenna to transmit a wireless signal from a BTS to a receiver. The non-selected antennae may be disabled from transmitting signals to the receiver by suppressing the Walsh code and PN offsets of the BTS and receiver. The pathway manager may use criteria such as availability, proximity, reliability, and strength of signals and antennae to select an optimal antenna. Communications between the receiver and the antennae may be used to determine such criteria. By selecting an optimal antenna, the pathway manager may conserve energy from a BTS and reduce power requirements for an antenna system.

Abstract: A method for shaping beams in a radio communication system employs current weighting vectors determined from first weighting vectors. The first weighting vectors used for the beam shaping are chosen to be orthogonal to each other.

Abstract: A plurality of amplifiers corresponding to a plurality of types of transmitting signals are provided to amplify the transmitting signals to a power level at which they can be transmitted by radio. The amplifiers are driven by both power and a bias. The bias is supplied to one of the amplifiers that amplifies a to-be-transmitted transmitting signal.

Abstract: Input signals of each frame are encoded by mapping the signals onto a coordinate system dictated by the symbols of the previous frame, and symbols from a constellation are selected based on the results of such mapping. Received signals are detected by preprocessing the signals detected at each antenna with signals detected by the antenna at the immediately previous frame, and then applied to a maximum likelihood detector circuit, followed by an inverse mapping circuit.

Abstract: A method for amplifying diversity transmit signals includes receiving a transmit signal at a vector modulator, where the vector modulator processes the transmit signal to yield diversity transmit signals, amplifying each of the diversity transmit signals according to a gain using at least one power amplifier, and transmitting the amplified diversity transmit signals at a plurality of antennas.

Abstract: The object of the present invention is to improve the accuracy of channel estimation and increase downlink capacity when a base station transmits an individual channel using directional beams. The base station 10 according to the present invention comprises an individual channel transmitter 15 configured to transmit an individual channel into which pilot symbols are inserted; and an individual channel format creator 14 configured to create a format of the individual channel. The individual channel format creator 14 changes between a format of an individual channel which is to be transmitted using directional beams and a format of an individual channel which is to be transmitted using non-directional beams.

Abstract: The invention concerns a unit for sending from a base station to terminals in a telecommunications system, said unit comprising at least two sending channels or groups of sending channels adapted to send on a plurality of adjacent carrier frequencies, said channels being able to send in spatial diversity mode so that the same information may be sent by the channels or groups of channels on the same carrier frequency or frequencies. In this unit the channels or groups of channels use at least one common carrier frequency for sending in spatial diversity mode and at least one of the channels or groups of channels comprises at least one different frequency for sending without spatial diversity or with a lower degree of spatial diversity.

Abstract: Provided is a dual antenna diversity transmitter and system having improved power amplifier efficiency, and further comprising switches in the dual antenna diversity transmitter and system, to minimize a DC input power consumed by the power amplifier depending on the required transmitting output power and operate efficiently the power amplifier, whereby signal linearity can be maintained and the power amplifier can be efficiently operated in a more simplified manner, as compared to the conventional high efficiency power amplifier.

Abstract: For combining two received signals (#1, #2) from different reception routes, a control process for maximizing the level of a combined signal (maximum level combining process), a control process for combining the signals in phase with each other (in-phase combining process), a control process for minimizing a waveform distortion of the combined signal (minimum amplitude deviation type combining process), and a control process for performing both the minimum amplitude deviation type combining process and the maximum level combining process are alternatively switched by an EPS (endless phase shifter) control circuit (8) depending on a level detector output (101) and a waveform distortion detector output (102). These control processes are performed by controlling the EPS (1) to control the phase of the received signal (#2).

Abstract: There is provided a radio transmitting apparatus capable of improving spectrum efficiency and a transmission rate while maintaining communication quality. The present apparatus adaptively selects space multiplex where different information (transmission signal A?transmission signal B) is transmitted from a plurality of antennas with the same frequency, frequency multiplex where different information (transmission signal A?transmission signal B) is transmitted from the plurality of antennas with different frequencies, space diversity where the same information is transmitted from the plurality of antennas with the same frequency, and frequency diversity where the same information (transmission signal A=transmission signal B) is transmitted from the plurality of antennas with different frequencies according to circumstances of a propagation path.

Abstract: Disclosed is an adaptive transmit and receive method and device in a multiple-antenna wireless communication system. A transmit mode comprises different main transmit modes each of which includes one or both of a sub-transmit mode based on STBC and a sub-transmit mode based on SM. A receiver calculates an STBC performance parameter and a SM performance parameter, and a transmitter uses the parameters to determine a main transmit mode with maximum data rates and select a sub-transmit mode for minimizing power consumption. The transmitter channel-encodes, modulates and antenna-maps input data according to the selected transmit mode, and outputs results to the receiver. The receiver antenna/symbol-demodulates and channel-decodes the received data.

Abstract: A portable cellular phone system with an automatic answering telephone function can perform data communication and has automatic answering telephone functions installed on both the network side and a terminal unit side. This system includes a section for transferring a message recorded first by the automatic answering telephone function on the network side to the terminal unit side.

Abstract: A method and apparatus of increasing output power of a plurality of carriers of a wide-band multi-carrier base station system utilizes gain adjusting coefficients to adjust output amplitude of the carriers to satisfy the requirement of the wide-band base station system for different number of carriers and output power. The output power of each of or a part of the carriers is increased when the number of carriers is reduced. Under the premise of not modifying the hardware and satisfying the requirement of protocol specification, the wide-band base station system supports different number of carriers by setting software so that the output power of the respective carriers and the coverage of the base station can be increased when the carriers do not operate in a full configuration.

Abstract: Base station transmitter signals are combined more effectively through the use of anti-phase pilots between pairs of transmission paths. At the combiner, the pilots will cancel when the amplitude, phase, and delay of the two transmission paths entering the combiner are matched. As a result, the pilots will not appear at the output except when the alignment is incorrect. By detecting the residual pilot at the combiner output, the information is used to adjust the alignment of one of the transmission paths to match the other. The adjustments to the amplitude, phase, and delay are performed on the input signal, after the pilot injection.

Abstract: A system and method for enhancing the data rate of a WLAN. Through the deployment of a MIMO system, the data rate ordinarily expected of a SISO type system can be doubled. Yet, the MIMO system of the present invention can remain backward compatible with conventional WLAN standards implemented by typical SISO type system. In particular, the packet preamble of the MIMO packet of the present invention is similar to that of a conventional SISO system so as to be backward compatible with conventional SISO receivers. Additionally, the data model of the MIMO system can be configured to support the detection of symbols in the MIMO packet of the present invention. Importantly, the present invention can include a least squares soft-detector for use in a wireless LAN compatible MIMO system.

Abstract: A hybrid wireless optical and radio frequency (RF) communication link utilizes parallel free-space optical and RF paths for transmitting data and control and status information. The optical link provides the primary path for the data, and the RF link provides a concurrent or backup path for the network data, as well as a reliable and primary path for the control and status information. When atmospheric conditions degrade the optical link to the point at which optical data transmission fails, the hybrid communication link switches to the RF link to maintain availability of data communications. The switch may occur automatically, based on an assessment of the quality of the optical signal communicated through the optical path.

Abstract: An emergency and non-emergency transmitter receivable by broadcast band receivers in nearby vehicles, comprising a first signal generator for simultaneously providing a plurality of selectively spaced carriers having frequency spacings corresponding to the individual channels of the band to be covered and selectively providing amplitude modulation when used for the AM broadcast band, and a second signal generator providing an FM modulated signal, which when combined with the signal from the first signal generator, covers various portions of the FM broadcast band to provide complete coverage thereof. A plurality of signals are generated in a portion of a selected band and modulated, according to the selected band mode, with a pre-stored and selectable voice alarm message.

Abstract: An emergency and non-emergency transmitter receivable by broadcast band receivers in nearby vehicles, comprising a first signal generator for simultaneously providing a plurality of selectively spaced carriers having frequency spacings corresponding to the individual channels of the band to be covered and selectively providing amplitude modulation when used for the AM broadcast band, and a second signal generator providing an FM modulated signal, which when combined with the signal from the first signal generator, covers various portions of the FM broadcast band to provide complete coverage thereof. A plurality of signals are generated in a portion of a selected band and modulated, according to the selected band mode, with a pre-stored and selectable voice alarm message.