Qualcomm

About: Qualcomm is a company organization based out in Farnborough, United Kingdom. It is known for research contribution in the topics: Wireless & Signal. The organization has 19408 authors who have published 38405 publications receiving 804693 citations. The organization is also known as: Qualcomm Incorporated & Qualcomm, Inc..

Propagation Path Loss Models for 5G Urban Micro- and Macro-Cellular Scenarios

Abstract: This paper presents and compares two candidate large-scale propagation path loss models, the alpha-beta-gamma (ABG) model and the close-in (CI) free space reference distance model, for the design of fifth generation (5G) wireless communication systems in urban micro- and macro-cellular scenarios. Comparisons are made using the data obtained from 20 propagation measurement campaigns or ray- tracing studies from 2 GHz to 73.5 GHz over distances ranging from 5 m to 1429 m. The results show that the one-parameter CI model has a very similar goodness of fit (i.e., the shadow fading standard deviation) in both line-of-sight and non-line-of-sight environments, while offering substantial simplicity and more stable behavior across frequencies and distances, as compared to the three-parameter ABG model. Additionally, the CI model needs only one very subtle and simple modification to the existing 3GPP floating-intercept path loss model (replacing a constant with a close-in free space reference value) in order to provide greater simulation accuracy, more simplicity, better repeatability across experiments, and higher stability across a vast range of frequencies.

Methods and apparatus for estimating departure time based on known calendar events

Abstract: A method and apparatus generating a departure alert for an event based on a current location. The method may comprises: obtaining scheduling data associated with a first event, wherein the first event scheduling data includes a first event time value and a first event location value, obtaining a device location value, obtaining a current time value, determining if the first event location value and the device location value differ by more than a event location threshold, upon a determination that the first event location value and the device location value differ by more than the event location threshold, estimating a first travel time value from the device location and the first event location, generating a departure time value by comparing the first event time value and the estimated first travel time value, and generating a departure alert by comparing the departure time value and the current time value.

Mobile station assisted timing synchronization in a cdma communication system

Abstract: In the present invention, the slave base station (64) attains synchronization with the reference base station (62) through messages (504) transmitted from and received by a mobile station (60) either in the soft handoff region between the reference base station (62) and the slave base station (64) or within a range which allows the mobile station (60) to communicate with the slave base station (64). When the mobile station (62) is not in communication with both the reference base station and the slave base station (62), then the round trip delay between the mobile station and the reference base station is measured by the reference base station (62). The reference base station (62) communicates the PN code used by the mobile station over the reverse link to the slave base station. The slave base station (64) acquires the signal (504) from the mobile station (60) and determines when the signal from the mobile station arrives. The slave base station (64) then makes and estimates as to the length of the delay between transmission of a signal from the mobile station (60) to the slave base station (64). Based upon these measurements and estimates, the slave base station (64) determines the error which is present in the slave base station system time.

Pilot transmission schemes for wireless multi-carrier communication systems

Abstract: Pilot transmission schemes suitable for use in wireless multi-carrier (e.g., OFDM) communication systems. These pilot transmission schemes may utilize frequency, time, or both frequency and time orthogonality to achieve orthogonality among the pilots transmitted by multiple base stations on the downlink. Frequency orthogonality is achieved by transmitting pilots on disjoint sets of subbands. Time orthogonality is achieved by transmitting pilots using different orthogonal codes (e.g., Walsh codes). The pilots may also be scrambled with different scrambling codes, which are used to randomize pilot interference and to enable identification of the transmitters of these pilots. Pilot interference cancellation may be performed to improve performance since subbands used for data transmission by one transmitter may also be used for pilot transmission by another transmitter. Pilot interference is estimated and then subtracted from received symbols to obtain pilot-canceled symbols having improved quality.

A communication device for providing multimedia in a group communication network

Abstract: A system and method for providing group communication services is disclosed. Each of a plurality of group communication devices coverts media, such as video, audio, image and/or data into data packets suitable for transmission over a data network, such as the Internet. The data packets are selectively transmitted through the data network to a communications manager. The communications manager acts as a configurable switch, allowing communications from any communication device to be selectively routed to the plurality of communication devices based on the types of the communication devices and/or the requests received from the corresponding users. The communications manager further allows users of other communication systems and devices to participate in group communications with each other.