摘要:
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.
摘要:
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.
摘要:
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.
摘要:
Cellular signals or other wireless signals/messages are introduced into a building or to an outside location by transmitting packets corresponding to those signals over a data network and low cost cables to designated locations within the data network. Once the designated packets containing the signals reach the destination, they are then broadcast over the air to a terminal capable of receiving the wireless message. In a first embodiment, an in-building gigabit Ethernet network, such as that currently existing presently in many buildings, is used to distribute radio signals indoors. Instead of transmitting the radio signals over the air from a repeater connected to a base station, coded baseband signals generated by the coding processor (e.g., a CDMA Modem Unit) in the base station are packetized and sent over the Ethernet network to radio processing equipment and antennas distributed throughout the building. The radio processing equipment strips the packet headers from the baseband signal packets so those signals can be broadcast via the antennas to one or more mobile terminals.