Signal generator with display unit

• US 20040184554A1
• Filed: 05/18/2004
• Published: 09/23/2004
• Est. Priority Date: 05/18/2001
• Status: Active Grant

• Current Assignee: Rohde & Schwarz GmbH & Company KG
• Original Assignee: Rohde & Schwarz GmbH & Company KG
• Inventors: Pauly, Andreas, Braunstorfinger, Thomas
• Granted Patent: US 7,480,328 B2
• Time in Patent Office: Days
• US Class Current: 375/295
• CPC Class Codes: H04B 17/23 Indication means, e.g. displays, alarms, audible means

Abstract

A signal generator includes a baseband unit, generating a digital, and an I/Q modulator, modulating the digital baseband signal. A storing memory stores a time slot of said digital baseband signal and an optical display unit represents the digital baseband signal stored in said memory according to a predetermined representation mode.

Claims

1. Signal generator (1) comprising

a baseband unit (2) that generates a digital baseband signal,

an I/Q modulator (5) that modulates the digital baseband signal,

a recording memory (15) that records a time segment of the digital baseband signal, and

a visual display device (23) that displays the digital baseband signal stored in the recording memory (15) in a predeterminable display mode.

2. Signal generator according to claim 1, characterized in that at least one or more signal modification units (3, 4) are provided between the baseband unit (2) and the IN modulator (5) and in that the signal at the input and/or output of each signal modification unit (3, 4) can be routed to the recording memory (15).

3. Signal generator according to claim 2, characterized in that one of the signal modification units (3, 4) is a noise unit (3) and/or a fading unit (4) and/or a distortion unit.

4. Signal generator according to any one of claims 1 to 3, characterized in that the baseband unit (2) has at least one sampling rate converter (resampler) (10a, 10b) and the signal at the input and/or output of each sampling rate converter (10a, 10b) can be routed to the recording memory (15).

5. Signal generator according to any one of claims 1 to 4, characterized in that the baseband unit (15) has at least one pulse-shaping filter (9a, 9b) and the signal at the input and/or output of each pulseshaping filter (9a, 9b) can be routed to the recording memory (15).

6. Signal generator according to claim 5, characterized in that the code-domain power of a CDMA signal is displayed on the display device (23) and the symbol clock rate (f_sym) signal upstream of the pulse-shaping filter (9a, 9b) is routed to the recording memory (15).

7. Signal generator according to any one of claims 1 to 6, characterized in that there is provided, upstream of the recording memory (15) one or more decimation units (18a) that decimate the data stream of the digital baseband signal by a decimation factor N by selecting only every Nth data element.

8. Signal generator according to claim 7, characterized in that the start of the time segment that the recording memory (15) records is controlled by a trigger signal (TS).

9. Signal generator according to claim 8, characterized in that the trigger signal (TS) is chosen in such a way that a plurality of time segments can be joined seamlessly to one another.

10. Signal generator according to claim 8, characterized in that the trigger signal (TS) is chosen in such a way that the time segments each cover periodic segments of a periodic baseband signal.