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                                                                  EXHIBIT 3.1(a)

                       CERTIFICATE OF OWNERSHIP AND MERGER
                                       OF
                                 SMDI SUB, INC.
                                      INTO
                           STANFORD MICRODEVICES, INC.

                     ---------------------------------------

                     Pursuant to Section 253 of the General
                    Corporation Law of the State of Delaware

                     ---------------------------------------

     Stanford Microdevices, Inc. (the "Corporation"), pursuant to Section 253 of
the General Corporation Law of the State of Delaware (the "DGCL"), hereby
certifies as follows:

     FIRST: The Corporation is incorporated pursuant to the General Corporation
Law of the State of Delaware.

     SECOND: The Corporation owns 100% of the outstanding shares of each class
of capital stock of SMDI Sub, Inc., a Delaware corporation (the "Subsidiary").

     THIRD: The Board of Directors of the Corporation, by resolutions adopted at
a meeting duly held on September 17, 2001, has authorized the merger of the
Subsidiary with and into the Corporation (the "Merger"). A true copy of such
resolutions is attached hereto as Exhibit A. Such resolutions have not been
                                  ---------
modified or rescinded and are in full force and effect on the date hereof.

     FOURTH: The Corporation shall be the surviving corporation of the Merger
(the "Surviving Corporation").

     FIFTH: At the effective time of the Merger the name of the Surviving
Corporation shall be changed to Sirenza Microdevices, Inc.

     SIXTH: The Merger shall become effective upon the filing of this
Certificate of Ownership and Merger with the Secretary of State of the State of
Delaware.

                  [Remainder of Page Intentionally Left Blank]

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IN WITNESS WHEREOF, Stanford Microdevices, Inc. has caused this Certificate of
Merger to be executed in its corporate name as of this 18th day of September,
2001.

                                     STANFORD MICRODEVICES, INC.


                                     /s/  Thomas Scannell
                                     -------------------------------------------
                                     Thomas Scannell
                                     Vice President, Finance and Administration,
                                     Chief Financial Officer, Secretary
                                     and Assistant Treasurer

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                                    EXHIBIT A
                                    ---------

                             RESOLUTIONS ADOPTED BY

                             THE BOARD OF DIRECTORS

                                       OF

                           STANFORD MICRODEVICES, INC.

                               September 17, 2001

     RESOLVED, that the proper officers of Stanford Microdevices, Inc., a
Delaware corporation (the "Corporation") be, and each of them hereby is,
authorized and directed to cause the formation of SMDI Sub, Inc. (the
"Subsidiary"), as a wholly owned subsidiary of the Corporation under and
pursuant to the laws of the State of Delaware; that the Subsidiary shall be
merged with and into the Corporation (the "Merger") and the Corporation shall be
the surviving corporation (the "Surviving Corporation") of the Merger; that in
connection with the Merger the Surviving Corporation shall change its name to
Sirenza Microdevices, Inc.; that, from and after the effective time of the
Merger, the certificate of incorporation of the Corporation shall be the
certificate of incorporation of the Surviving Corporation, the bylaws of the
Corporation shall be the bylaws of the Surviving Corporation, the officers and
directors of the Corporation shall be the officers and directors of the
Surviving Corporation, the outstanding common stock and other securities of the
Corporation shall remain outstanding as the common stock and other securities of
the Surviving Corporation and the outstanding common stock of the Subsidiary
shall be cancelled; that the proper officers of the Corporation be, and each of
them hereby is, authorized and directed, in the name and on behalf of the
Corporation, to prepare and execute a Certificate of Ownership and Merger and to
cause such Certificate of Ownership and Merger to be filed with the Secretary of
State of the State of Delaware pursuant to Sections 103 and 253 of the General
Corporation Law of the State of Delaware; and that the merger shall be effective
at the time stated in such Certificate of Ownership and Merger; and

     FURTHER RESOLVED, that, upon the effectiveness of the Merger, the proper
officers of the Corporation be, and each of them individually hereby is,
authorized, empowered and directed to prepare or cause to be prepared a form of
a certificate to evidence shares of common stock of the Corporation, par value
$0.001 per share ("Common Stock"), reflecting the change in corporate name
resulting from the Merger; that such form of Common Stock certificate shall be
adopted, to the same extent as if presented to and adopted by the Board of
Directors hereof, provided that a copy thereof be affixed to these resolutions
by the Secretary; that the proper officers of the Corporation be, and each of
them individually hereby is, authorized, empowered and directed to execute such
Common Stock certificates; that any and all signature on such Common Stock
certificates may be facsimile signatures; and that in case any officer, transfer
agent or registrar who has signed or whose facsimile signature has been placed
upon such Common Stock certificates shall have ceased to be such officer,
transfer agent

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or registrar before the issuance thereof, it may be issued by the Corporation
with the same effect as if such person were such officer, transfer agent or
registrar at the date of issue; and

     FURTHER RESOLVED, that the proper officers of the Corporation be, and each
of them hereby is, authorized and directed to prepare, execute, deliver and file
or cause to be prepared, executed, delivered and filed any and all documents and
to take any and all actions with federal, state, local and foreign authorities
and with The Nasdaq Stock Market, Inc., or such other entities as they or any of
them may deem necessary or appropriate to effect the corporate name change and
Merger contemplated by the foregoing resolutions and to carry out fully the
purpose and intent of such resolutions; and

     FURTHER RESOLVED, that the proper officers of the Corporation be, and each
of them hereby is, authorized, empowered and directed, in the name and on behalf
of the Corporation, to take all actions necessary to adopt and approve the
proposed name change of Stanford Microdevices, Inc. to Sirenza Microdevices,
Inc.; and

     FURTHER RESOLVED, that all actions heretofore taken by any officer or
director of the Corporation in connection with the matters contemplated by the
foregoing resolutions be, and they hereby are, approved, adopted, ratified,
confirmed and accepted in all respects.