Northrop Grumman Systems Corporation

United States of America As Represented by the Secretary of the Air Force

Westinghouse Electric Corporation

Other

Ronald W Minarik

Kenneth M Schmidt

Michael V Pascale

Benjamin F Weigand

William C Phillips

Walter M Dirndorfer

Robert S Prill

Arnold B Siegel

Frederick H Harris

John W Gipprich

Stephen P Caldwell

Wayne B Lloyd

Robert R Willmore

Dale R Logan

Dickron Mergerian

William F List

Charles L Hilterbrick

Donald A Bozanic

Robert J Bernhard

Demetrios J Matsakis

Marvine Harris Jr

Richard H Nogay

A system that partitions or divides the functions of a radio into channels and divides the functions of each channel into two major functions: 1) antenna interface and power amplification; and 2) hardwired mixing, modulation/demodulation and signal processing and further partitions the mixing through signal processing functions into the functions of a) programmable analog mixing and b) programmable digital modulation/demodulation and signal processing. Control and user interface functions, if needed for a particular application can also be functionally partitioned. A typical received signal pathway will encounter an antenna module, an antenna interface and power amplification module, a receiver module partitioned into an analog submodule that performs mixing and down conversion to produce a common intermediate frequency signal and a digital submodule that further down converts the intermediate frequency signal, demodulates the signal and performs the other signal processing necessary to provide a useful information signal. A typical transmitter pathway includes a transmitter module partitioned into a digital submodule that performs signal processing and modulation and an analog submodule that performs upconversion and mixing, followed by a power amplification and interface module and an antenna module. Control and user interface modules can also be provided along with modules that perform additional processing and information security functions.

Digitally programmable multifunction radio system architecture

A radio transmitter is structured to provide frequency hopping of transmitted leakage signals in addition to RF hopping of the RF output signal. A digital computer controls a digital tuner, a TLO, a FLO, and an IF unit to provide the RF hopping and to provide digital-tuner frequency hopping and IF hopping thereby enabling the frequency hopping of transmitted leakage digital tuner and IF signals.

Frequency hopping radio transmitter apparatus and method providing very

An antenna interface unit (AIU) for providing low power loss, fault tolerant connectivity between multiple transmitters and an antenna, and between multiple receivers and the antenna. The antenna interface unit also eliminates single point failures in a transmit/receive (T/R) mechanism. The antenna interface unit includes (a) a power combiner/splitter connectable to the antenna; a receive channel connected to the power combiner/splitter; and a transmit channel connected to the power combiner/splitter. The transmit channel is a different channel from the receive channel. The receivers are connectable to the antenna via the receive channel and through the power combiner/splitter. The transmitters are connectable to the antenna via the transmit channel and through the power combiner/splitter. Different variations of the receive channel and the transmit channel are provided by using different combinations of power combiners and power splitters.

Low-loss, fault-tolerant antenna interface unit

A programmable digital radio is configured to perform navigation functions. A receiver in the programmable digital radio receives analog signals from a navigation unit and digitizes the analog signals to produce digital navigation signals. The digital navigation signals are processed digitally and valid navigation information is determined. Processing includes generation of baseband signals including in-phase signals and quadrature signals, AM demodulation, filtering, decimating, demultiplexing, discrete fourier transformation, and function processing according to a selected function. The selected functions may include Localizer, Marker Beacon and Glideslope.

Digitally programmable radio modules for navigation systems

A common transmit module of a programmable digital radio has a digital submodule which receives a bit stream and produces a modulated IF signal, and an analog submodule which receives the modulated IF signal and converts the modulated IF signal to a frequency corresponding to a specific type of radio function. The digital submodule includes (a) a sequential/parallel instruction set processor for signal processing and control, (b) a reconfigurable format unit, and (c) a modulator which receives the output signals of the reconfigurable format unit and produces the modulated oscillation signal. The analog submodule includes (a) a tunable local oscillator that produces a tunable local oscillation signal, (b) fixed local oscillators that produce fixed local oscillation signals, and (c) a mixing unit that receives the modulated IF signal, the tunable local oscillation signal and the fixed local oscillation signals, selectively mixes the fixed local oscillation signals with the modulated oscillation signal to produce non-final IF signals, and mixes a non-final IF signal with the tunable local oscillation signal to produce a final converted signal for transmission at the frequency corresponding to the specific type of radio function.

Common transmit module for a programmable digital radio

A digital submodule is included in a software programmable common receive module for receiving IF signals and producing a serial bit stream. The digital submodule is programmable based on a selected application of a plurality of radio applications and, if present, a selected function of a plurality of functions of the selected radio application. The digital submodule may include an analog to digital converter for converting IF signals received from an analog submodule into digital signals. The digital signals are supplied to a programmable signal processing unit which is configured, according to the selected radio application and, if present, the selected function, to perform control functions, processing and analysis of the digital signals and generate output signals. The output signals are then formatted by a formatting unit producing formatted digital signals. The formatted digital signals are then supplied to a system bus. The programmable signal processing unit may include a digital downconverter for selective use depending on the selected application of radio communication, for generating a base signal. Additionally, a central processing unit is included to perform further signal processing for selected radio application.

Common receive module for a programmable digital radio

A programmable digital radio is configured to perform transponder functions. A receiver in the programmable digital radio receives analog signals from an interrogator and digitizes the analog signals to produce digital interrogation signals. The digital interrogation signals are processed digitally and valid interrogations are detected. Processing includes detection of pulses, determination of each pulse's threshold, determination of intervals between pulses and whether the intervals meet mode criteria, and determination of priority of output of digital messages encoded in the pulses. At least one message is supplied to a transmit module in the programmable radio. The transmit module performs diversity processing on the received message to determine to which received signal to reply, produces reply data and modulates the reply data to produce intermediate frequency signals. The intermediate frequency signals are then converted to analog signals which are transmitted to the interrogator.

Digitally programmable radio modules for transponder systems

A wideband RF-to-IF frequency converter providing multiple use of frequency conversion components for many different types of RF input signals. In specific examples, many different types of signals for communication, navigation, and for interrogation are processed through at least partly common frequency-conversion channels. Such RF input signals in the range from approximately 2 MHz to 2,000 MHz are converted to output IF frequencies, such as 1 MHz and 30 MHz, for further processing in the common receiver. Some narrow band signals, after conversion to IF, are subjected to off-center filtering in relatively broadband IF filters. Input RF filters are not used. Among several frequency conversion stages, only one of the local oscillator signals is tunable; but it is made tunable in relatively small, precise steps by using a double phase-locked loop arrangement in the frequency synthesizer.

Wide band radio-frequency converter having multiple use of intermediate

A variable analog delay line apparatus utilizing a plurality of tapped SAW devices that are connected in series by single pole multi-throw switch units. The amount of delay is determined by the switch throw arm of the switch unit that is associated with the SAW device. The delay times are added serially to obtain the needed delay.

Variable analog delay line

A signal processing system is disclosed that divides a broad band of input signals into separate channels separated by stopbands and permits operation in the crossover frequencies occuring at these stopbands. A triplexer separator receives and divides the broad band of input signals into a first, second and third band of signals, and sends them respectively to a first, second and third signal channel. The first and third signal channels are narrow bands which respectively occur at the lower and upper frequency end of the broad band of input signals. The second signal channel is identical to the broad band of input signals. In normal operation the first, second and third signal channels separately and independently conduct their respective signals to a triplexer combiner, where they are recombined. However, if signal processing is planned at crossover frequencies in the stopbands of either the first or third signal channel, the first or third band of signals can be directed into the second signal channel to permit such operation.

Adaptive microwave channelization

A double sideband suppressed carrier modulator apparatus for combining two serrodyne (i.e., single sideband) modulators to achieve double sideband, suppressed carrier modulation. An RF input signal is divided into two carrier signals which are 90 degrees out of phase and applied to the serrodyne modulator units. The modulated signals from the modulators are combined in a 90 degree power divider to provide a double sideband suppressed carrier modulated output signal.

Double sideband generation with serrodyne modulators

An electric discharge gas laser utilizing a seedant material which is cooled prior to the main laser discharge. The seedant is ionized prior to the cooling process and prior to the main discharge, this pre-ionization maintaining the seedant material in a gaseous state even in view of the lowered temperature for a sufficient time so as to give the required ionization levels.

Apparatus for modifying the liquefication or solidification point of a

An autoalignment system for a laser having a pair of reflector assemblies capable of providing six degrees of freedom of movement to the reflector element formed as part of each of the reflector assemblies. Each reflector assembly is made up of a reflector unit, a gimbal knuckle joint and a translator mechanism. The interconnection between the reflector unit and the gimbal knuckle joint provides for two degrees of freedom while the translator mechanism and its interconnection with the gimbal knuckle joint provides the additional four degrees of freedom. Cooling of the reflector elements is accomplished by way of a coolant system which is incorporated within the autoalignment system of the laser, while motivation of the autoalignment system is in the form of a plurality of drivers operably connected to the various elements of the reflector assembly. During utilization of the system in a vibrational environment, the autoalignment system maintains the correct relationship between the reflecting elements of the laser as well as providing sufficient cooling thereof.

Laser autoalignment system

A method and means of generating an electron spin echo signal having a relatively higher output frequency than the input frequency of the applied 90.degree. and 180.degree. RF pulses applied to an electron spin echo sample located in a static magnetic field by increasing the magnitude of the Zeeman magnetic field by a predetermined amount after the application of the 90.degree. and 180.degree. pulses. Also the spin echo sample is situated in a microwave cavity which has two resonant frequency modes, the first of which has a relatively high Q while the second has a relatively low Q. The 90.degree. and 180.degree. RF pulses are applied to the system at the first resonant frequency having the high Q while the spin echo signal is coupled out of the system at the second resonant frequency having the low Q.

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Lutherville, MD, United States of America

Ronald W Minarik