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Technion - Israel institute of technology department of Electrical Engineering. הטכניון - מכון טכנולוגי לישראל הפקולטה להנדסת חשמל. High speed digital systems laboratory. המעבדה למערכות ספרתיות מהירות. Midterm Presentation. Transfer fax over IP in cellular networks.
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Technion - Israel institute of technology department of Electrical Engineering הטכניון - מכון טכנולוגי לישראלהפקולטה להנדסת חשמל High speed digital systems laboratory המעבדה למערכות ספרתיות מהירות Midterm Presentation Transfer fax over IP in cellular networks Performed by: Carmel Yuval, Mishael Avihoo Instructor: Orbach Mony Cooperated with: Qualcomm Israel
High speed digital systems laboratory המעבדה למערכות ספרתיות מהירות Project Goal Transmit fax page from a fax machine to a computer and receive a fax page from a computer to a fax machine.
High speed digital systems laboratory המעבדה למערכות ספרתיות מהירות Block Diagram Control/ feedback SLIC DSP Fax Computer
High speed digital systems laboratory המעבדה למערכות ספרתיות מהירות Functional Description • Converting analog fax transmission to a digital signal • Decoding and interpreting the digital signal • Determine the fax call state from the digital signal using state machine, negotiating accordingly with the computer • Transmitting an image information to the computer using AT-Commands • Repeating the process for the case of the computer initiating the fax call
High speed digital systems laboratory המעבדה למערכות ספרתיות מהירות Interfaces
High speed digital systems laboratory המעבדה למערכות ספרתיות מהירות Interfaces (cont.) • ProSLIC • Parallel port – to controller (computer). • Analog – to phone line (200-2200Hz). • Serial – PCM digital signal to DSP (2.048MHz). • DSP • Serial RS-232 – to PC emulating IWF (4800-19200bps). • EZ-ICE – for debugging DSP (9600bps). • Serial – PCM digital signal to ProSLIC (2.048MHz).
High speed digital systems laboratory המעבדה למערכות ספרתיות מהירות Data Rates and Bandwidths
High speed digital systems laboratory המעבדה למערכות ספרתיות מהירות Built In Tests • Program debugging • Using VisualDSP+EZ-ICE. • Log points – TBD. • ProSLIC • Power on – Power LEDs. • Computer interface – Using program. • Phone line interface – Tone generation, using fax. • PCM interface – TBD.
High speed digital systems laboratory המעבדה למערכות ספרתיות מהירות Built In Tests (cont.) • DSP • Power on – Power LEDs. • Computer interface – TBD. • PCM interface - TBD. • EZ-ICE interface – TBD.
PSTN IWF MSC BSC FAX BTS Wireless MS HOST DSP FAX High speed digital systems laboratory המעבדה למערכות ספרתיות מהירות Complete System Overview
High speed digital systems laboratory המעבדה למערכות ספרתיות מהירות Complete System Overview (cont.) • MS – Mobile Station - Wireless communication device, contains the DSP, interfaces the fax to the cellular network. • BTS – Base Transceiver Station – Connects the MS to the cellular network using wireless interface. • BSC – Base Station Controller – Controls Resources.
High speed digital systems laboratory המעבדה למערכות ספרתיות מהירות Complete System Overview (cont.) • MSC – Mobile Switching Center – The cellular network PSTN. • IWF – Inter Working Function – Connects the cellular network to PSTN using modems (Dial up, fax, etc.). • PSTN – Public Switching Telephone Network – connects subscribers.
High speed digital systems laboratory המעבדה למערכות ספרתיות מהירות Project’s Alternatives • External Modem – Of the shelf solution, cheap, but large, can not generate PSTN functions. • Canceling Vocoder (voice compression algorithm) – Not supported.
High speed digital systems laboratory המעבדה למערכות ספרתיות מהירות ProSLIC • Provides a complete analog telephone interface. • “Subscriber Line Interface Circuit”. • codec. • DTMF functions. • Signal generation functions (linefeed). • Consist A/D, D/A, DC to DC converter, programmable signal generator, signal detector and much more on one chip.
High speed digital systems laboratory המעבדה למערכות ספרתיות מהירות ProSLIC (cont.) • codec (coder decoder): • Convert analog signal to PCM. • Convert PCM to analog signal. • Comply with A-Law, μ-Law.
High speed digital systems laboratory המעבדה למערכות ספרתיות מהירות ProSLIC (cont.) • DTMF functions: • “Dual Tone Multi Frequency”. • Two frequency generators for generating DTMF signals. • DTMF detection.
High speed digital systems laboratory המעבדה למערכות ספרתיות מהירות ProSLIC (cont.) • Linefeed: • on-hook voltage. • off-hook loop current. • on-hook transmission ringing voltage.
High speed digital systems laboratory המעבדה למערכות ספרתיות מהירות DSP Software • The project consist of written program which works with a host processor. • The written software will be alternated in order to disable the host interface.
High speed digital systems laboratory המעבדה למערכות ספרתיות מהירות DSP Software (cont.) IWF HOST DSP Interrupts DPR (SM)
High speed digital systems laboratory המעבדה למערכות ספרתיות מהירות DSP Software (cont.) • The host and the DSP shares RAM for exchange commands and data. • When the host or the DSP puts new data at the shared memory, they initiates interrupt to inform the other side about the new data.
DSP Host Module High speed digital systems laboratory המעבדה למערכות ספרתיות מהירות DSP Software (cont.) DPR (SM) Interrupts PC
DSP DPR (SM) PC Interrupts Host Module High speed digital systems laboratory המעבדה למערכות ספרתיות מהירות DSP Software (cont.) • The host module is a software function in the DSP. • The host module will connect the DSP to the PC (IWF) via RS-232 (SPORT1). • The module will acts as the host when reading and writing into the shared memory. • The module will initiate interrupts to the DSP and respond to such.
High speed digital systems laboratory המעבדה למערכות ספרתיות מהירות Timetable
