Abstract: A multichip module is assembled using flip-chip bonding technology, a stencil printable solder paste and standard surface mount equipment for interconnecting signaling input/output contact pads on devices within such a multichip module. The disclosed assembly process makes the heretofore difficult and expensive flip chip bonding technique achievable at low cost. The flip chip bonding technique is simplified by use of a solder paste which includes desirable reflow alignment, fluxing and printability characteristics. These desirable characteristics allow the assembly process to be further economically achieved by permitting the use of standard surface mount equipment in the process. High volume production of standard inexpensive modules are thus possible through this process while also achieving the advantage of high density interconnections afforded through the flip-chip bonding technology.

Abstract: A voice-actuated switching system connects one or more microphones to an audio line in accordance with the output signal levels from each of the microphones. To reduce the effects of degradation of speech signals due to reverberation and noise pickup, the switching system uses directional microphones housed in a circular enclosure and arranged in a conference array configuration with response patterns aimed outwardly from the center of the enclosure. The switching system also uses a voting algorithm to select for activation the appropriate microphones indicative of the position of one or more people speaking and a variable weighting factor for gradually turning on or off the signal from each activated microphone that is coupled to the audio line. Typically one microphone will be selected to monitor a person speaking. Since its response pattern is normally pointed in the direction of the person speaking, it is less sensitive to speaker echo due to reverberation.

Abstract: A telephone message system overcomes the problems and limitations of presently available systems that seek to enhance inter-and intra-premises communications. The system comprises a controller unit with Caller ID capabilities and one or more adjunct units that are all bridged onto a single wire-pair at a user's residential location in a parallel electrical connection. For facilitating a message routing capability, a mailbox of groups of telephone numbers are associated with a particular party at the residence. These telephone numbers are preprogrammed into the controller unit so that upon receipt of an incoming call from one of these telephone numbers, identified through caller ID, the incoming call is associated with the particular called party and the controller unit routes the incoming call directly to the called party's mail box where the calling party is able to leave a message.

Abstract: A bimodal portable telephone provides cellular service and improved cordless service in a common handset. Operation of the bimodal portable telephone in a cellular telephone system provides telephone service over a wide geographical area of coverage through operation with multiple cellular bases and in a cordless telephone system provides telephone service over a localized geographical area of coverage through operation with an associated cordless base. The cordless service provides improved performance over convention cordless telephone service by advantageously employing a frequency hopping spread spectrum modulation technique for communications between the portable telephone and the cordless base unit. This improved performance achieves increased operating range of the cordless telephone system.

Abstract: A .pi./4 delay spread detection and compensation arrangement effectively detects distortion due to multipath delay spread in a digital channel and compensates for this distortion with minimum circuit complexity. An improvement in the bit error rate performance for a differential detector in the receiver is achieved through use of a detected direct current (DC) component, which is proportional to the amount of multipath delay spread on the digital channel. This DC component is used in the differential detector for compensating for this delay spread. In addition, the differential detector also provides a channel quality measure of the level of delay spread on the digital channel for use by the receiver in selecting either the differential detector or an equalizer for decoding of the data on the digital channel.

Abstract: A cordless telephone set advantageously includes a wireless test mode accessible by a user for evaluating performance levels of operating parameters in the cordless telephone set in diverse geographical locations. When configured in a normal operating mode, the cordless telephone set provides normal wireless communications. When configured in the wireless test mode, the cordless telephone set provides audible and visual input to its user for use in determining a maximum acceptable separation distance for satisfactory communications between a telephone handset unit and its associated base unit in the cordless telephone set. This operating range determination for the cordless telephone set is achieved by providing a simulation of a recognizable tone, such as dial tone, to which a user subjectively listens while testing an application environment.

Abstract: A caller-ID telephone station having a caller-ID based directory of telephone numbers automatically adapts its directory to compensate for a change to the area code in which the telephone station is located. The caller-ID telephone station stores the area code for all incoming caller-ID telephone numbers along with each telephone number received. The telephone station also stores its home area code. This home area code is inputted by a user during an initialization step when the telephone station is first installed, moved to a different area code or the station's locale is changed to a different area code. In response to a request from the user for dialing a telephone number entered into the directory, the telephone station compares the stored area code received as part of the caller-ID telephone number with the stored home area code and determines from this comparison whether to include or omit the received area code as part of the dialed telephone number.

Abstract: A cordless telephone provides for improved conservation of battery power in a handset unit when this unit is located remote from an associated base unit and in a standby state for a prolonged period of time. While the handset unit is in the standby state for less than a predetermined time period, this unit resides in a low-power monitoring mode which includes deactivating certain internal circuitry and reducing by a first time period the on-time state of other internal circuitry for conserving battery power. After being in the standby state for greater than the predetermined time period, the handset unit continues to reside in the low-power monitoring mode, but further reduces by a second time period the on-time state of the other internal circuitry for greater conservation of battery power. Communications between the handset unit and the base unit is easily reestablished by either one of these units irrespective of the time that the handset unit has been in the standby state.

Abstract: A cordless telephone system is arranged for extending the operating range of a cordless telephone portable unit within such system. The cordless telephone system comprises a plurality of cordless telephone stations that plug into any available wall telephone jack and may share the intrapremises telephone wire-pair with one or more existing corded telephone stations without interference. Each cordless telephone station consists of a cordless telephone base unit and its associated cordless telephone portable unit. Although each of the portable units is associated with a particular base unit, all of the portable units are able to operate with any of the base units in the system. As a user of a portable unit with a call in progress roams about a premises, all base units monitor the quality of the radio frequency signal received from the portable unit.