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                                                                    Exhibit 4(a)


                  SECOND RESTATED CERTIFICATE OF INCORPORATION
                                       OF
                               ALLEN TELECOM INC.

         ALLEN TELECOM INC., a corporation organized and existing under the laws
of the State of Delaware, hereby certifies as follows:


         I. The name of the corporation is Allen Telecom Inc.

         II. The name under which the corporation was originally incorporated is
ALN, Inc.

         III. The date on which the original Certificate of Incorporation of the
corporation was filed with the Secretary of State of the State of Delaware is
February 3, 1969.

         IV. The corporation filed a Restated Certificate of Incorporation on
November 20, 1984 (the "First Restated Certificate of Incorporation").

         V. This Second Restated Certificate of Incorporation only restates and
integrates and does not further amend the provisions of the corporation's First
Restated Certificate of Incorporation as heretofore amended or supplemented, and
there is no discrepancy between those provisions and the provisions of this
Second Restated Certificate of Incorporation.

         VI. This Second Restated Certificate of Incorporation was duly adopted
by the Board of Directors of the corporation in accordance with Section 245 of
the General Corporation Law of Delaware.

         VII. The text of the Second Restated Certificate of Incorporation of
the corporation is herein set forth in full:

         FIRST. The name of the corporation is

                               ALLEN TELECOM INC.

         SECOND. The address of its registered office in the State of Delaware
is The Corporation Trust Center, No. 1029 Orange Street, in the City of
Wilmington, County of New Castle. The name of its registered agent at such
address is The Corporation Trust Company.

         THIRD. The nature of the business or purposes to be conducted or
promoted is:

                  To carry on and conduct any and every kind of manufacturing,
         distribution and service business; to manufacture, process, fabricate,
         rebuild, service, purchase or otherwise acquire, to design, invent or
         develop, to import or export, and to distribute,


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         lease, sell, assign or otherwise dispose of and generally deal in and
         with raw materials, products, goods, wares, merchandise and real and
         personal property of every kind and character; and to provide services
         of every kind and character.

         To conduct any lawful business, to exercise any lawful purpose
and power, and to engage in any lawful act or activity for which corporations
may be organized under the General Corporation Law of Delaware.

         In general, to possess and exercise all the powers and privileges 
granted by the General Corporation Law of Delaware or by any other law of 
Delaware or by this Certificate of Incorporation, together with any powers 
incidental thereto, so far as such powers and privileges are necessary or
convenient to the conduct, promotion or attainment of the business or purposes
of the corporation.

         FOURTH. The total number of shares of stock which the corporation shall
have authority to issue is fifty-three million (53,000,000), of which three
million (3,000,000) shares shall be Preferred Stock, without par value, and
fifty million (50,000,000) shares shall be Common Stock of the par value of $1
per share. The Preferred Stock shall be issued from time to time in one or more
series with such distinctive serial designations and (a) may have such voting
powers, full or limited, or may be without voting powers; (b) may be subject to
redemption at such time or times and at such prices; (c) may be entitled to
receive dividends (which may be cumulative or noncumulative) at such rate or
rates, on such conditions, and at such times, and payable in preference to, or
in such relation to, the dividends payable on any other class or classes or
series of stock; (d) may have such rights upon the dissolution of, or upon any
distribution of the assets of, the corporation; (e) may be made convertible
into, or exchangeable for, shares of any other class or classes or of any other
series of the same or any other class or classes of stock of the corporation, at
such price or prices or at such rates of exchange, and with such adjustments;
and (f) shall have such other relative, participating, optional or other special
rights, qualifications, limitations or restrictions thereof, all as shall
hereafter be stated and expressed in the resolution or resolutions providing for
the issue of such Preferred Stock from time to time adopted by the board of
directors pursuant to authority so to do which is hereby vested in the board.

         Each share of Common Stock shall entitle the holder thereof to one
vote, in person or by proxy, at any and all meetings of the stockholders of the
corporation, on all propositions before such meetings.

         The number of authorized shares of any class of stock of the
corporation, including but without limitation the Preferred Stock and the Common
Stock, may be increased or decreased by the affirmative vote of the holders of a
majority of the stock of the corporation entitled to vote.

         FIFTH. In furtherance and not in limitation of the powers conferred by
statute, the board of directors is expressly authorized:

                  To make, alter or repeal the by-laws of the corporation.

         To authorize and cause to be executed mortgages and liens upon the real
and personal property of the corporation.


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                  To set apart out of any of the funds of the corporation
         available for dividends a reserve or reserves for any proper purpose
         and to abolish any such reserve in the manner in which it was created.

         By a resolution of a majority of the whole board, to designate one or
more committees, each committee to consist of two or more of the directors of 
the corporation. The board may designate one or more directors as alternate
members of any committee, who may replace any absent or disqualified member at
any meeting of the committee. Any such committee, to the extent provided in the
resolution or in the by-laws of the corporation, shall have and may exercise
the powers of the board of directors in the management of the business and
affairs of the corporation, and may authorize the seal of the corporation to be
affixed to all papers which may require it; provided, however, the by-laws may
provide that in the absence or disqualification of any member of such committee
or committees, the member or members thereof present at any meeting and not
disqualified from voting, whether or not he or they constitute a quorum may
unanimously appoint another member of the board of directors to act at the
meeting in the place of any such absent or disqualified member.

         When and as authorized by the affirmative vote of the holders of a 
majority of the stock issued and outstanding having voting power given at a
stockholders' meeting duly called upon such notice as is required by statute,
or when authorized by the written consent of the holders of a majority of the
voting stock issued and outstanding, to sell, lease or exchange all or
substantially all of the property and assets of the corporation, including its
good will and its corporate franchises, upon such terms and conditions and for  
such consideration, which may consist in whole or in part of money or property
including shares of stock in, and/or other securities of, any other corporation
or corporations, as its board of directors shall deem expedient and for the
best interests of the corporation.

         SIXTH. The number of directors of the corporation shall be such as from
time to time shall be fixed by or in the manner provided in the by-laws, which
shall not be less than three.

         SEVENTH. The corporation shall indemnify each director, officer,
employee or agent of the corporation and each person who is or was serving at
the request of the corporation as a director, officer, employee or agent of
another corporation, partnership, joint venture, trust or other enterprise in
the manner and to the extent provided in the by-laws of the corporation as the
same may be amended from time to time.

         No director shall be personally liable to the corporation or any
stockholder for monetary damages for breach of fiduciary duty as a director,
except for any matter in respect of which such director shall be liable under
Section 174 of Title 8 of the Delaware Code (the Delaware General Corporation
Law) or any amendment thereto or successor provision thereto or shall be liable
by reason that, in addition to any and all other requirements for such
liability, he or she (a) shall have breached his or her duty of loyalty to the
corporation or its stockholders, (b) shall not have acted in good faith or, in
failing to act, shall not have acted in good faith, (c) shall have acted in a
manner involving intentional misconduct or a knowing violation of law or, in
failing to act, shall have acted in a manner involving intentional misconduct or
a knowing violation of law or (d) shall have derived an improper personal
benefit. Neither the amendment nor repeal of this paragraph, nor the adoption of
any provision of this Certificate of Incorporation inconsistent with

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this paragraph, shall eliminate or reduce the effect of this paragraph in
respect of any matter occurring, or any cause of action, suit or claim that, but
for this paragraph, would accrue or arise, prior to such amendment, repeal or
adoption of an inconsistent provision.

         EIGHTH. Whenever a compromise or arrangement is proposed between this
corporation and its creditors or any class of them and/or between this
corporation and its stockholders or any class of them, any court of equitable
jurisdiction within the State of Delaware may, on the application in a summary
way of this corporation or of any creditor or stockholder thereof, or on the
application of any receiver or receivers appointed for this corporation under
the provisions of Section 291 of Title 8 of the Delaware Code or on the
application of trustees in dissolution or of any receiver or receivers appointed
for this corporation under the provisions of Section 279 of Title 8 of the
Delaware Code order a meeting of the creditors or class of creditors, and/or of
the stockholders or class of stockholders of this corporation, as the case may
be, to be summoned in such manner as the said court directs. If a majority in
number representing three-fourths in value of the creditors or class of
creditors, and/or of the stockholders or class of stockholders of this
corporation, as the case may be, agree to any compromise or arrangement and to
any compromise or arrangement, the said compromise or arrangement and the said
reorganization shall, if sanctioned by the court to which the said application
has been made, be binding on all the creditors or class of creditors, and/or on
all the stockholders or class of stockholders, of this corporation, as the case
may be, and also on this corporation.

         NINTH. Meetings of stockholders may be held within or without the State
of Delaware, as the by-laws may provide. The books of the corporation may be
kept (subject to any provision contained in the statutes) outside the State of
Delaware at such place or places as may be designated from time to time by the
board of directors or in the by-laws of the corporation. Elections of directors
need not be by written ballot unless the by-laws of the corporation shall so
provide.

         TENTH. Any corporate action upon which a vote of stockholders is
required or permitted may be taken without a meeting or vote of stockholders
with the written consent of stockholders having not less than fifty-one percent
(51%) of all of the stock entitled to vote upon the action if a meeting were
held; provided that in no case shall the written consent be by holders having
less than the minimum percent of the total vote required by statute for the
proposed corporate action and provided that prompt notice be given to all
stockholders of the taking of corporate action without a meeting by less than
unanimous written consent.

         ELEVENTH. The corporation reserves the right to amend, alter, change or
repeal any provision contained in this Certificate of Incorporation, in the
manner now or hereafter prescribed by statute, and all rights conferred upon
stockholders herein are granted subject to this reservation.



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         IN WITNESS WHEREOF, Allen Telecom Inc. has caused this Second Restated
Certificate of Incorporation to be signed by Robert G. Paul, its President and
Chief Executive Officer, and attested to by McDara P. Folan, III, its Secretary,
this 1st day of May, 1998.

                                            ALLEN TELECOM INC.



                                            By:      /s/ Robert G. Paul
                                                     ---------------------------
                                                     Robert G. Paul, President
                                                     and Chief Executive Officer






ATTEST:


/s/ McDara P. Folan, III
-----------------------------------
McDara P. Folan, III, Secretary





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