MULTI-FUNCTION DEVICE WITH POSITIONING SYSTEM AND SHARED PROCESSOR

• US 20090102710A1
• Filed: 08/05/2008
• Published: 04/23/2009
• Est. Priority Date: 11/01/2002
• Status: Active Grant

• Current Assignee: CSR Technology Incorporated (Qualcomm, Inc.)
• Original Assignee: CSR Technology Incorporated (Qualcomm, Inc.)
• Inventors: Roy, Benjamin Van, Bloebaum, Scott, Chou, Andrew
• Granted Patent: US 7,800,535 B2
• Time in Patent Office: Days
• US Class Current: 342/357.770
• CPC Class Codes: G01S 19/25 involving aiding data received from a cooperating element, e.g. assisted GPS
• CPC Class Codes: G01S 19/29 carrier including Doppler, related G01S19/246 takes precedence
• CPC Class Codes: G01S 19/37 Hardware or software details of the signal processing chain
• CPC Class Codes: G01S 5/0036 of measured values, i.e. measurement on mobile and position calculation on base station
• CPC Class Codes: H04B 1/7102 with transform to frequency domain
• CPC Class Codes: H04B 2201/70715 with application-specific features

Abstract

A multi-function device with a positioning function and a real time positioning engine is disclosed. The device contains also a shared processor used by the positioning function and other functions of the device, such as a mobile radio-communication function. The positioning engine performs in real time the most computational intensive calculations of the positioning function, such as downsampling, Doppler mixing and correlation calculations. Since the received signal need not be stored, the memory requirements of the positioning function are significantly reduced if aiding data is available.

Claims

1. A multi-function mobile device capable of radio communication with a data network/multimedia reproduction and determination of a position based on a positioning signal, comprising:

a positioning engine in said mobile device that performs real-time calculations with said positioning signal;

a shared memory coupled to said positioning engine that (1) receives and stores in real time results of said real-time calculations, each said result comprising correlations under a hypothesis relating the position signal with a selected signal source and a selected Doppler shift and (2) stores results of the calculation for said radio communication or multimedia reproduction functions;

a shared processor coupled to said memory that (1) retrieves and processes said results to generate positioning information and (2) performs calculation for said radio communication or multimedia reproduction.

2. The device of claim 1, wherein said memory is shared with other processors or co-processors of the mobile device.

3. The device of claim 1, wherein said results are associated with a plurality of source-Doppler pairs and said shared processor allocates a memory block for each source-Doppler pair to store said positioning engine results and said allocated memory block can be later released by the shared processor for its use or use by other processors.

4. The device of claim 1, wherein said positioning engine results are associated with a plurality of source-Doppler pairs and said shared processor allocates a memory block for each source-Doppler pair to store said positioning engine results and said allocated memory block can be later released by the shared processor for its use or use by other processors.

5. The device of claim 1, wherein such shared memory is accessed by said positioning engine and said shared processor through a shared memory interface and memory requests by the positioning engine and by the processor have to be arbitrated to allow the positioning engine to access the shared memory to keep up with memory bandwidth requirement of real time calculation of said position signal.

6. A device to process a received positioning signal in real time and to conduct radio communication with a data network or to process multimedia data comprising:

a shared memory between processors;

a first processor coupled to said memory including;

means for downsampling said positioning signal from an intermediate frequency, to yield a baseband signal;

means for mixing and accumulating said baseband signal, to yield an accumulated signal;

means for correlating and accumulating signal with a reference signal, to yield a plurality of correlation values; and

means for writing said plurality of correlation values to said memory, each correlation written being a correlation calculated under a hypothesis relating the position signal with a signal source and a Doppler shift; and

a second processor coupled to said memory (1) retrieving said plurality of correlation values for further processing, and (2) conducting said radio communication or multimedia processing.