Abstract: The present invention provides for a wireless radio frequency (“RF”) modem that plugs into a host computer and shares a central processing unit and memory with the host computer, wherein principal modem functions are distributed between the modem and the host computer. In one embodiment, the modem performs RF conversion, and the host computer performs baseband processing and protocol stack control. In another embodiment, the modem performs RF conversion and baseband processing, and the host computer performs protocol stack control.

Abstract: The present invention provides for a wireless radio frequency (“RF”) modem that plugs into a host computer and shares a central processing unit and memory with the host computer, wherein principal modem functions are distributed between the modem and the host computer. In one embodiment, the modem performs RF conversion, and the host computer performs baseband processing and protocol stack control. In another embodiment, the modem performs RF conversion and baseband processing, and the host computer performs protocol stack control.

Abstract: The present invention provides for a wireless radio frequency (“RF”) modem that plugs into a host computer and shares a central processing unit and memory with the host computer, wherein principal modem functions are distributed between the modem and the host computer. In one embodiment, the modem performs RF conversion, and the host computer performs baseband processing and protocol stack control. In another embodiment, the modem performs RF conversion and baseband processing, and the host computer performs protocol stack control.

Abstract: The present invention provides for a wireless radio frequency (“RF”) modem that plugs into a host computer and shares a central processing unit and memory with the host computer, wherein principal modem functions are distributed between the modem and the host computer. In one embodiment, the modem performs RF conversion, and the host computer performs baseband processing and protocol stack control. In another embodiment, the modem performs RF conversion and baseband processing, and the host computer performs protocol stack control.

Abstract: The present invention is directed at a method and apparatus for updating a detachable software configurable wireless radio frequency modem that uses operating software. The RF modem uses an attached host computing device to download an operating software update to the RF modem's memory to reconfigure the RF modem. There is also a recovery feature that allows the original version of the RF modem's operating software to be saved and recovered if an attempt to update the RF modem's operating software is unsuccessful.

Abstract: The present invention provides for a wireless radio frequency (“RF”) modem that plugs into a host computer and shares a central processing unit and memory with the host computer, wherein principal modem functions are distributed between the modem and the host computer. In one embodiment, the modem performs RF conversion, and the host computer performs baseband processing and protocol stack control. In another embodiment, the modem performs RF conversion and baseband processing, and the host computer performs protocol stack control.

Abstract: A wireline interface permitting a cellular telephone transceiver to originate and receive calls using both cellular and wireline services. The invention permits a subscriber unit to operate as a standard cellular telephone when it is disconnected from a land-based telephone line, and as both a full-featured telephone and a full-featured cellular telephone when it is connected to a wireline. A wireline interface circuit provides on/off hook, calling identification, and audio signal conversion functions on the wireline signals. A duplexed audio switch permits the audio signals provided to and from a cellular-type handset to be connected either to the cellular transceiver or to the wireline interface adapter, under control of the user. As a result, any handset-provided functions such as speed dialing or hands-free operation are available for use when operating on a wireline circuit as well as when operating on a cellular radio link.

Abstract: An electronic device has a circuit whose operation is adjustable by changing a variable component responsive to stored data. The electronic device also has a processor responsive to a stored program for controlling the circuit by receiving new input data and changing the variable component by replacing the stored data with the new input data. Preferably the electronic device has radio frequency circuits for transmitting and receiving a radio frequency signal, and audio frequency circuits for relaying and reproducing an audio signal. For calibration and adjustment during assembly or servicing, the electronic device is connected to automatic testing, checking and adjustment equipment including a computer that provides the input data to change the variable component as required. The calibration or adjustment is made as a series of progressively better approximations to the required valve.

Abstract: A control circuit for a radio frequency (rf) amplifier having multiple selectable power output levels in response to a plurality of input control signals is presented. The rf amplifier includes a variable gain input which is responsive to the control circuit. The control circuit includes an attenuator coupled to the output of the rf amplifier for providing an attenuated rf signal and an detector coupled to the output of the attenuator for generating a DC output signal which is substantially linearly related to the magnitude of the rf signal output by the rf amplifier. The control circuit also includes a means coupled to the input control signals for selecting one of a plurality of amplification factors. An amplifier is used to amplify the DC output signal generated by the detector using the selected amplification factors. The amplified output is coupled to the variable gain input of the rf amplifier.

Abstract: A circuit board assembly for a cellular telephone system or the like is described. A housing encloses a printed circuit board. The housing comprises a frame including an outer wall surrounding the periphery of the printed circuit board and a pair of cover plates engaging the outer edges of the outer wall of the frame. The printed circuit board is secured to the frame, and the frame is secured between the cover plates by fasteners which pass through holes in the printed circuit board. A plurality of internal walls on the frame isolate components on the printed circuit board and engage a ground line on the printed circuit board. The printed circuit board is a multi-layer board designed to permit signal lines to pass underneath the ground lines. Components are amounted on both sides of the printed circuit board.

Abstract: A compact and inexpensive variable resistor circuit has a value of resistance that can be set by a data signal. The variable resistor includes a number of variable individual resistances connected in series, and an electronic switch connected in parallel across each individual resistance. The values of the individual resistances are chosen to include a basic resistance value and a compensating resistance value, which corresponds to the impedance of the associated electronic switch in its closed state. The basic value is chosen from the progression 2.sup.0, 2.sup.1, 2.sup.2, 2.sup.3, and so on, so that the resistance of the variable resistor corresponds to the binary value of data applied to control the electronic switches. Other aspects of the invention include input and control circuitry which is designed to minimize its size and allow it to be packaged on an integrated circuit.

Abstract: An improved radio frequency (RF) coupler for providing two or more secondary signals from a primary RF signal. The RF coupler has a primary coupling element and two or more secondary coupling elements for providing the two or more secondary signals. The secondary RF coupling elements are offset and nonoverlapping with respect to one another along the axis of the primary coupling element so as to reduce the cross coupling and interference between the secondary elements. The offset relationship between secondary coupling elements allows for optimal design control over the coupling between each secondary coupling element and the primary coupling element. In one embodiment, the spatial area required for the coupling elements is reduced by introducing U-shaped portions in the primary coupling element and at least one of the secondary coupling elements. In another embodiment, the secondary coupling elements are provided on separate substrates to further reduce cross interference.