摘要:
An antenna assembly, a receiver, and a system configured to superimpose a first received signal from a first antenna and an intermediate signal based on a second received signal from a second antenna onto a single cable. The antenna assembly includes a mixer and an adjustable local oscillator (ALO) that frequency shift the second received signal to generate the intermediate signal. The output frequency of the ALO is controlled by a control signal superimposed on the single cable that is output by the receiver. With this arrangement, a plurality of antennas or antenna elements can be connected to a receiver using a single coaxial cable. Such an arrangement is particularly desirable to manufacturers of automobiles and other vehicles. Also, the receiver can detect if the output frequency of the ALO needs to be adjusted, and so close-loop control of the output frequency is possible.
摘要:
A communication system and method thereof are provided, wherein the system includes a first satellite configured to re-transmit at least a first transmitted signal at a first frequency band, a second satellite configured to re-transmit the first transmitted signal at a second frequency band, and a first terrestrial repeater configured to re-transmit the first transmitted signal at a third frequency band. The system further includes a third satellite configured to re-transmit a second transmitted signal at the third frequency band that is different than the first transmitted signal re-transmitted by the first and second satellites, such that the first signal re-transmitted by the first terrestrial repeater, and the second signal re-transmitted by the third satellite interfere with one another, wherein the first signals re-transmitted by the first satellite, the second satellite, and the first terrestrial repeater includes substantially the same data.
摘要:
An antenna system is provided having switched directional antennas. The antenna system includes a first antenna for receiving signals within a first directional coverage zone, and a second antenna for receiving signals within a second directional coverage zone. According to one embodiment, the first and second antennas are located on a vehicle. The system has a device to detect orientation of the vehicle. The system further includes a receiver having control circuitry for controlling selection of the signals received from the first and second antennas based on orientation of the vehicle, location of one or more sources, and antenna coverage zones for the first and second antennas.
摘要:
The present invention provides a method, receiver and transmitter for use in a SDAR system. The method involves generating a first modulated signal based on first input data. Additional modulation is superimposed on the first modulated signal based on additional input data, being spread across a plurality of symbols in the first modulated signal in a predetermined pattern to generate a modified signal which is then transmitted. The modified signal is decoded by performing a first demodulation of the first modulated signal then additional demodulation is performed to obtain additional input data. The superimposing step uses a plurality of offset sequence values to add the additional modulation to the first modulated signal. The offset sequence may appear as a pseudo-random distribution of offset sequence values, and may include at least one zero offset value. Alternatively, the additional modulated signal may be a formed as a direct sequence spread spectrum modulation and the offset sequence appearing as a pseudo-noise distribution. A Hadamard matrix sequence may be used as the direct sequence code.
摘要:
A receiver device and method of receiving a plurality of signals are provided, wherein the receiver device includes at least one antenna element and circuitry in communication with the at least one antenna element. The at least one antenna element is configured to receive at least a first signal having a first polarization and a second signal having a second polarization, wherein the first polarization is different than the second polarization. The circuitry is configured to process and emit an output based upon at least one of the received first and second signals, wherein the first signal is received at a first reception elevation angle with respect to the at least one antenna element that is greater than a second reception elevation angle of the second signal with respect to the at least one antenna element, and the first and second signals are transmitted at substantially the same frequency.
摘要:
A system and method of injecting audio content into a radio system is provided. The method includes the steps of receiving in a radio receiver a first RF signal from an antenna and processing the signal at a select frequency within a radio frequency band. The method also includes the step of providing audio content from an auxiliary device. The method also includes the step of modulating the audio content from the auxiliary device and replicating the modulated signal to generate a replicated RF signal at the multiple frequencies within the radio frequency band. The method further includes the step of injecting the replicated RF signal into the radio receiver.
摘要:
A communication system and method of communicating signals to a plurality of different types of receivers is provided. At least one transmitter transmits hierarchically modulated high priority and low priority signals as a single frequency network. At least one satellite re-transmits the high priority signal in a first circularly polarized direction and the low priority signal in a second circularly polarized direction. At least one of a first receiver having a single antenna is configured to receive the high priority signal in the first circularly polarized direction and switched to receive the low priority signal in the second circularly polarized direction, and a second receiver having a first antenna is configured to receive the high priority signal in the first circularly polarized direction, and a second antenna is configured to receive the low priority signal in the second circularly polarized direction substantially simultaneously.
摘要:
The present invention involves a method for transmitting data having primary and secondary data. A first transmit signal is transmitted from a first communication satellite wherein the first transmit signal is produced when the transmitter modulates the primary and secondary data on a first carrier wave associated with the first communication satellite, with secondary data having a first polarity. A second transmit signal is transmitted from a second communication satellite wherein said second transmit signal is produced when the transmitter modulates the primary and secondary data on a second carrier wave associated with the second communication satellite with secondary data having a second polarity opposite the first polarity.
摘要:
A system and method for communicating and re-using frequencies is provided, which includes a source provider, at least one transmitter, and a plurality of antennas. The transmitter transmits source data along a plurality of signal paths including a first signal at a first frequency transmitted along a first satellite signal path, a second signal at a second frequency transmitted along a second satellite signal path, and a terrestrial signal transmitted along a terrestrial signal path. The terrestrial signal frequency is substantially the same as one of the first and second signal frequencies. The antennas receive signals, and include a first antenna for receiving at least the terrestrial signal along the terrestrial signal path and a second antenna for receiving at least the first signal along the first satellite signal path, the second signal along the second satellite signal path, and the terrestrial signal along the terrestrial signal path.
摘要:
A receiver includes a channel decoder select circuit, a plurality of communication channels, at least one maximum ratio combiner circuit, and a forward error correction circuit. The plurality of communication channels receive wireless information from channel demodulators and are in communication with respective channel decoder circuits, which are in communication with the channel decoder select circuit. The at least one maximum ratio combiner circuit receives the wireless information from the plurality of communication channels. The output of the maximum ratio combiner is communicated to the forward error correction circuit, the output of which is communicated to the channel decoder select circuit. A pseudo bit error measurement feedback signal communicated to the maximum ratio combiner from one of the plurality of channel decoder circuits. A method for finding wireless satellite signals that minimizes errors in a receiver system is also disclosed.